Quaternary and environmental geology of part of the West Fork Basin, Gallatin County, Montana
by Clifford Montagne
A thesis submitted to the Graduate Faculty in partial fulfillment of the requirements for the degree of
MASTER OF SCIENCE in Earth Science (Geology)
Montana State University
© Copyright by Clifford Montagne (1971)
Abstract:
The West Fork (of the Gallatin River) lies in the Madison Range between Bozeman and West
Yellowstone, Montana, It is the site of Big Sky of Montana, a proposed year round recreation and real
estate development, Field work was partially funded by the National Science Foundation for a project
entitled Impact of a Large Recreation Area on a Semiprimitive Environment.
The West Fork basin is a structural and topographic basin in the Northern Rocky Mountain
Physiographic Province. It is bounded on the north by the crystalline Spanish Peaks and on the west by
the Lone Mountain intrusive complex. The basin exposes Cretaceous bedrock.
Quaternary geology was mapped jointly by A. Kehew, H. Walsh and the writer, pre-Wisconsin glacial
till is associated with a 2 million year old welded tuff. Till position and regional correlation indicate the
existence of a pre-Wisconsin ice cap over the Spanish Peaks, filling the West Fork basin with ice. Bull
Lake (early Wisconsin) glaciers filled the North Fork and Beehive valleys with ice and terminated on
or near the main basin floor. Pinedale glaciers were smaller than the Bull Lake glaciers, Hillslopes of
Cretaceous bedrock, mantled with Bull Lake till, slid during the Pinedale deglaciation.
Neoglacial moraines and talus flows are found in the highest cirques.
Wisconsin glaciers, originating in the east facing cirques on Lone Mountain, reached the vicinity of the
upper village site (S30, T6S, R3E). An inactive Neoglacial rock glacier now occupies the cirque. It is
partially covered by an active rock glacier.
Landsliding is still active, especially where hillslope equilibrium is disturbed by construction. Excess
water, alternating folded sandstones and shales, clays, steep, slopes, and till overload have caused past
and present sliding.
Potential rockfalls and snow avalanches pose threats to mountain use.
The proposed upper village site lies on outwash and till which covers shale bedrock. North of this site
are some active slide tension cracks. Soils mapping is correlated with the surficial geology. Many soil
boundaries correspond to surficial geology boundaries. Clay soils developed on shale are poor building
sites.
Some areas with unique natural habitats should be left as natural preserves. I n p r e s e n t i n g t h i s t h e s i s i n p a r t i a l f u l f i l l m e n t o f th e r e q u i r e ­
m en ts f o r a n ad v an c ed d e g re e a t M ontana S t a t e U n i v e r s i t y , I a g re e
t h a t th e L i b r a r y s h a l l make i t f r e e l y a v a i l a b l e f o r i n s p e c t i o n .
I
f u r t h e r a g r e e t h a t p e r m is s io n f o r e x t e n s i v e co p y in g o f t h i s t h e s i s
f o r s c h o l a r l y p u rp o s e s may be g r a n te d by my m ajo r p r o f e s s o r , o r , i n
h i s a b s e n c e , by th e D i r e c t o r o f L i b r a r i e s .
I t i s u n d e r s to o d t h a t
any co p y in g o r p u b l i c a t i o n o f t h i s t h e s i s f o r f i n a n c i a l g a in s h a l l
n o t be a llo w e d w ith o u t my w r i t t e n p e r m is s io n .
S ig n a tu r e
D ate
P y /_________
QUATERNARY AND ENVIRONMENTAL GEOLOGY OF PART OF
THE WEST FORK BASIN, GALLATIN COUNTY, MONTANA
by
CLIFFORD MONTAGNE
A t h e s i s s u b m itte d t o th e G ra d u a te F a c u lty i n p a r t i a l
f u l f i l l m e n t o f t h e r e q u ir e m e n ts f o r th e d e g re e
of
MASTER OF SCIENCE
in
E a r t h S c ie n c e (G eology)
A pproved:
C hairm an , E xam ining C om m ittee
MONTANA STATE UNIVERSITY
Bozeman, M ontana
A u g u st, 1971
Ack n owledgem ents
The w r i t e r th a n k s h i s p a r e n t s , who in tr o d u c e d him t o g eo lo g y and
s u p p o r te d th e p r e s e n t s tu d y i n e v e r y way. H is f a t h e r , Jo h n M ontagne,
was th e G e o lo g ic I n v e s t i g a t o r f o r th e N a tio n a l S c ie n c e F o u n d a tio n
p r o j e c t an d p r o v id e d h e lp i n th e f i e l d an d o f f i c e . Through P r o f e s s o r
C. C. B r a d l e y 's i n i t i a t i v e , th e N a tio n a l S c ie n c e F o u n d a tio n s tu d y
became a r e a l i t y .
I n a d d i t i o n t o b e in g a n e ig h b o r an d f r i e n d , he
s e rv e d a s th e w r i t e r ' s M ajor P r o f e s s o r . P r o f . B r a d le y , D r. V. M itc h e ll
and D r. D. Dunn gave in v a lu a b le h e l p i n th e p r e p a r a t i o n o f t h i s t h e s i s .
D r. J . H. Rumley and D r. G. A1 N ie ls e n p r o v id e d a s s i s t a n c e i n b o ta n y
an d s o i l s .
The w r i t e r th a n k s Jim an d P a t t y G o o d rich o f th e 320 R anch,
who in t r o d u c e d him t o th e c o u n try an d i t s way o f l i f e .
Sam Smeding
a llo w e d th e h u n tin g camp t o b e u s e d a s a b a s e f o r f i e l d w ork. From
k e e p in g camp t o p r o o f r e a d i n g , Jo a n M ontagne c o n t r i b u t e d t o th e p r o j e c t
i n a l l ways p o s s i b l e .
-iv TABLE OF CONTENTS
■
INTRODUCTION
L o c a tio n
P h y s io g r a p h ic S e t t i n g
G e o lo g ic S e t t i n g
............................ .... , .
P re v io u s G e o lo g ic Work
. . . . . . . . . .
c
C lim a te . . . . . . . . . . . .
................... . . . . . . . .
F lo r a a n d F auna
^
C u rre n t Use . . . . . .
. . . . . . . . . . . . . . . .
Scope and M ethod o f S tu d y
............................ , ,
D e f i n i t i o n o f E n v iro n m e n ta l G eology . . . . . . . . . . .
O b je c tiv e s o f S tu d y . . . . . . . . . . . .
................... ,
3
3
.
.
.
.
.
»
4
6
9
10
11
11
13
14
QUATERNARY GLACIAL AND SURFICIAL GEOLOGY
I n t r o d u c t i o n ............................................................
-^ Q u a te rn a ry G l a c i a l C o r r e l a t i o n s i n t h e Rocky M ou n tain s . .
Use o f S o i l s i n Age C o r r e l a t i o n s
. . . . . . . . . . . . .
P re -W is c o n s in G l a c i a t i o n i n West F o rk . . . . . . . . . .
N o rth F o rk B u ll Lake G l a c i a t i o n an d R e la te d S lid i n g . . . .
N o rth F o rk P in e d a le G l a c i a t i o n
. . . . . . . . . . . . . .
N e o g la c ia tio n
^
.
G l a c i a t i o n i n th e H anging V a lle y . . . . . . . . . . . . .
B eeh iv e C reek B u ll Lake G l a c i a t i o n s an d R e la te d L a n d s lid e s
B eeh iv e P in e d a le G l a c i a t i o n s
^
.
B eeh iv e N e o g la c ia l F e a t u r e s
r ... . . . .
.
M o o n lig h t C reek P in e d a le G l a c i a t i o n . . . . . . . . . . .
Lone M o untain W isc o n sin G l a c i a t i o n
. . . . . . . . . . .
I n a c t i v e Rock G l a c i e r . . ................... . . . . . . . . . . .
A c tiv e Rock G l a c i e r ..............................................
A d d iti o n a l Mass Movement F e a t u r e s . . . . . . . . . . . .
R ecent S lid in g . . . . . . . . . . . . . . . . . . . .
1970 L a n d s lid e . . . . . . . . . . . . . . . . . . . .
C auses o f S l i d i n g . . . . . . . . . . . . . . . . . . . .
R o c k f a ll
.
Snow A v a la n c h e s
.
P re -W is c o n s in W elded T u ff and T i l l
. . . . . . . . . . .
16
16
19
22
22
29
32
33
34
43
45
45
46 .
48
49
54
54
55
56
58
59
61
ADDITIONAL ASPECTS OF ENVIRONMENTAL GEOLOGY
In tro d u c tio n . . . . .
............................................... . . . . . . .
U pper V i l l a g e A rea ...........................
Road B u i l d i n g .......................
'-’S o i l s C o r r e l a t i o n s . . . . . . . . . . . . . . . . . . . .
N a tu r a l A re a s . . . . . . . . . . . . . . . . . . . . . .
66
66
74
74
79
-V S u g g e s tio n s f o r F u r t h e r S tu d y
80
REFERENCES CITED
APPENDIX
S tra tig ra p h y
87
S
1
T
—VI—
LIST OF PLATES AND FIGURES
P la te I
P la te I I
I.
2a.
2b,
3.
4.
5,.
6a,
6b.
7.
8.
9.
1 0 a. .
View o f Lone M ountain C irq u e .....................................
L ocal S e ttin g
................................................................. .... . „ .
T o p o g ra p h ic map o f s tu d y a r e a » ..................................... .
G l a c i a t i o n i n th e Rocky M o u n tain s .....................................
18
S o i l s d e v e lo p e d on B u ll Lake an d P in e d a le T i l l . . . .
21
G l a c i a l f e a t u r e s i n N o rth F o rk „ .
23
P i c t u r e o f B u ll Lake s o i l p r o f i l e
. . . . . . . . . .
25
S o i l d e v e lo p e d on B u ll Lake T i l l
...........................
26
L a n d s lid e r e a c t i v a t e d by lo g g in g r o a d ...........................
27
B u ll Lake an d P in e d a le s o i l p r o f i l e s a lo n g N o rth F o r k . 30
E a s t f a c i n g c i r q u e c a rv e d fro m s o u th f a c i n g b a s in , , 32
G l a c i a l an d s u r f i c i a l f e a t u r e s i n v i c i n i t y of
B e e h iv e B a s in
‘
. 35
IOb „ C irq u e s o f B ee h iv e B a s in an d th e H anging V a lle y
. , .. 36
l l a . . C o n c e n tr ic l a n d s l i d e s c a r p s
,
. 39
l l b . P e rc h e d swamps an d ponds . . . . . . . . . . . . . . .
39
H e . T i l l m a n tle d s lid e - s lu m p b lo c k s
. . . . . . . . . . .
40
1 2 . View from A n d e s ite t o B eeh iv e B a s in . . . . . . . . .
41
1 3 . L a n d s lid e s c a r p i n B u ll Lake t i l l
. . . . . . . . . .
42
14. A l l u v i a l f i l l b e h in d B eeh iv e P in e d a le te r m in a l
P o s i t i o n . . . ; .......................................... .... .........................
44
1 5 . R e l a ti o n o f U le r y s L akes t o B eeh iv e P in b d a le
T e rm in a l p o s i t i o n
45
16. G l a c i a l f e a t u r e s o f Lone M ountain
50
1 7 . A c tiv e r o c k g l a c i e r
. , . , ....................................
51
18. A r e a l v ie w o f Lone M ountain ro c k g l a c i e r s
. . . . . .
52
1 9 . A v alan c h e p a t h s on W ilso n P e a k ................................
60
2 0 a . C la y s o i l on s h a le b e d ro c k
69
2 0 b . Sandy s o i l on s a n d s to n e b e d ro c k
. .........................................
70
2 1 . View o f c l e a r c u t a r e a (u p p e r v i l l a g e s i t e ) . . . . . .
72
2 2 . C reek d r a i n i n g c l e a r c u t a r e a d u rin g r a i n
. . . . . .
73
2 3 . C o r r e l a t i o n o f s o i l s an d s u r f i c i a l g e o lo g y . . . . . .
76
2 4 . Map o f a r e a s u n d e s ir a b l e f o r c o n s t r u c t i o n
. . . . . .
81
CN I ''. CO
F ig u r e
E n v iro n m e n ta l G eology o f th e West F o rk B a s in , G a l l a t i n
C o u n ty , M ontana
I n f e r r e d C r o s s - S e c tio n B-Bf
-v iiABSTRACT
The West F o rk ( o f th e G a l l a t i n R iv e r) l i e s i n t h e M adison Range
b etw een Bozeman an d W est Y e llo w s to n e , M ontana, I t i s th e s i t e of B ig
Sky o f M ontana, a p ro p o s e d y e a r ro u n d r e c r e a t i o n an d r e a l e s t a t e de­
v e lo p m e n t, F i e l d w ork was p a r t i a l l y fu n d e d by th e N a tio n a l S c ie n c e
F o u n d a tio n f o r a p r o j e c t e n t i t l e d Im p ac t o f a L arg e R e c r e a tio n A rea
on a S e m ip r im itiv e E n v iro n m e n t.
Tlie W est F o rk b a s i n i s a s t r u c t u r a l an d to p o g r a p h ic b a s in in th e
N o rth e rn Rocky M o untain P h y s io g r a p h ic P r o v in c e . I t i s bounded on th e
n o r th b y th e c r y s t a l l i n e S p a n ish P eak s an d on th e w e st by th e Lone
M ountain i n t r u s i v e com plex. Tlie b a s i n e x p o se s C re ta c e o u s b e d ro c k .
Q u a te rn a ry g e o lo g y was mapped j o i n t l y by A. Kehew, H. Walsh and
th e w r i t e r , p r e - W is c o n s in g l a c i a l t i l l i s a s s o c i a t e d w ith a 2 m i l l i o n
y e a r o ld w eld ed f u f f .
T i l l p o s i t i o n an d r e g i o n a l c o r r e l a t i o n i n d i c a t e
th e e x i s t e n c e o f a p re -W is c o n s in i c e cap o v er th e S p a n is h P e a k s ,
f i l l i n g th e West F o rk b a s in w ith i c e . B u ll Lake ( e a r l y W isco n sin )
g l a c i e r s f i l l e d th e N o rth F o rk an d B eeh iv e v a l l e y s w ith i c e and
te r m in a te d on o r n e a r th e m ain b a s i n f l o o r . P in e d a le g l a c i e r s w ere
s m a lle r th a n th e B u ll Lake g l a c i e r s , H i l l s l o p e s o f C re ta c e o u s bed­
r o c k , m a n tle d w ith B u ll Lake t i l l , s l i d d u r in g th e P in e d a le d e g l a c i a - '
t i o n , N e o g la c ia l m o ra in e s an d t a l u s flo w s a r e fo u n d i n t h e h ig h e s t
c irq u e s .
W isc o n sin g l a c i e r s , o r i g i n a t i n g i n th e e a s t f a c i n g c i r q u e s on
Lone Mount a i n ,, r e a c h e d th e v i c i n i t y o f t h e u p p e r v i l l a g e s i t e (S 3 0 ,
T6S, R 3E ). A ttr a c tiv e N e o g la c ia l r o c k g l a c i e r now o c c u p ie s th e c i r q u e .
I t i s p a r t i a l l y c o v e re d by an a c t i v e r o c k g l a c i e r .
L a n d s lid in g i s s t i l l a c t i v e , e s p e c i a l l y w here h i l l s l o p e e q u i l ­
ib riu m v is d i s t u r b e d b y c o n s t r u c t i o n . E x cess w a te r , a l t e r n a t i n g f o ld e d
s a n d s to n e s a n d , s h a l e s , c l a y s , s te e p , s l o p e s , an d t i l l o v e r lo a d have
c a u s e d p a s t an d p r e s e n t s l i d i n g .
P o t e n t i a l r o c k f a l l s an d snow a v a la n c h e s p o s e t h r e a t s t o m o u n tain
use.
The p ro p o s e d u p p e r v i l l a g e s i t e l i e s on outw ash an d t i l l w hich
c o v e rs s h a le b ed ro ck .- N o rth o f t h i s s i t e a r e some a c t i v e s l i d e t e n - ■
s io n c r a c k s .
S o i l s m apping i s c o r r e l a t e d w ith t h e s u r f i c i a l g e o lo g y . Many
s o i l b o u n d a r ie s c o r r e s p o n d t o s u r f i c i a l g e o lo g y b o u n d a r ie s . C lay s o i l s
d e v e lo p e d on s h a le a r e p o o r b u il d in g s i t e s .
Some a r e a s w ith u n iq u e n a t u r a l h a b i t a t s s h o u ld b e l e f t a s n a t u r a l
p re se rv e s.
v
INTRODUCTION
F ig u r e I . E a s t s id e o f Lone M o u n tain , showing th e l a r g e
c i r q u e and ro c k g l a c i e r s .
—3 LOCATION
T h is r e p o r t c o n c e rn s th e E n v iro n m e n ta l an d Q u a te rn a ry g eo lo g y o f
a p o r t i o n o f th e d r a in a g e o f th e W est F o rk o f th e G a l l a t i n R iv e r ,
midway b etw ee n Bozeman an d West Y e llo w s to n e , M ontana.
The West F o rk
b a s i n i s th e p ro p o s e d s i t e o f B ig Sky o f M ontana, a r e c r e a t i o n and
l i v i n g d e v e lo p m e n t.
The p a r t i c u l a r a r e a u n d e r s tu d y i s bounded on th e
s o u th by th e M id d le F o rk o f th e West F o r k , . on th e n o r t h by ,the S p a n ish
B eak s, an d on th e w e st by a n o rth w a rd b e a r in g from Lone M ountain to
th e S p a n is h ,P e a k s *
PHYSIOGRAPHIC SETTING
The a r e a l i e s a t t h e s o u th e r n end o f th e N o rth e rn Rocky M o u n ta in "
P h y s io g r a p h ic P r o v in c e , a s u b d iv is io n o f th e Rocky M ountain System
(T h o m b u ry , 1964) .
L o c a l r e l i e f en co m p asses e l e v a t i o n s from th e
G a l l a t i n Canyon a t 6 ,0 0 0 f e e t ; t o th e sum m its o f th e S p a n is h P eaks and
Lone M o untain a t o v e r 11 ,0 0 0 f e e t .
I t i s a n a r e a o f h ig h r e l i e f , w ith
p e a k s , c i r q u e s an d m o d e ra te ly i n c i s e d can y o n s w hich d is c h a r g e t o th e
a l l u v i a l l e v e l o f th e G a l l a t i n R iv e r .
The to p o g ra p h y i s c o n t r o l l e d by
b e d ro c k s t r u c t u r a l f e a t u r e s an d m o d if ie d by g l a c i a t i o n an d o th e r m ass
m ovem ent.
Some s t r i k i n g exam p les o f s tre a m s u p e r p o s iti o n e x i s t *
The
t e r r a i n i s i n th e y o u t h f u l t o e a r ly - m a tu r e s ta g e o f geom orphic d e v e l­
opment .
—4—
GEOLOGIC SETTING
The m a t e r i a l f o r t h i s s e c t i o n h a s b een ta k e n fro m Swanson (1950 )
R a i l ( 1 9 6 1 ) , an d McMannis an d Chadwick (1964)«
9
F ig u r e 2a i s a s k e tc h
map show ing th e l o c a l s e t t i n g an d some s t r u c t u r a l f e a t u r e s .
F ig u r e
2b i s a to p o g r a p h ic map o f th e s tu d y a r e a .
The M a d is o n - G a lla tin u p l i f t i s a b ro a d a n t i c l i n a l u p l i f t and
f a u l t e d b lo c k w ith e x p o s u re s o f P re -C a m b ria n t o T e r t i a r y r o c k .
The
G a l l a t i n R iv e r flo w s n o r t h a lo n g a s t r u c t u r a l low i n th e m id d le o f th e
u p l i f t , s e p a r a t i n g t h e M adison Range on th e w est fro m th e G a l l a t i n
Range on th e e a s t .
The W est F o rk b a s i n ( s t r u c t u r a l an d to p o g r a p h ic )
l i e s i n th e M adison Range an d i s b o r d e r e d by th e G a l l a t i n R iv e r on th e
e a s t , th e S p a n is h P eak s on th e n o r t h , th e G a lla tin - M a d is o n D iv id e on
t h e w e s t, an d t h e Buck C reek a n t i c l i n e on th e s o u th .
The S p a n is h P eak s F a u l t i s a h ig h a n g le r e v e r s e f a u l t w hich r u n s
i n a n o r th w e s t d i r e c t i o n a lo n g th e n o r t h s id e o f th e West F o rk b a sin .The c r y s t a l l i n e S p a in s h P eak s r i s e on th e n o r th s i d e o f th e f a u l t ,
w hich h a s a t l e a s t 1 0 ,0 0 0 f e e t o f d is p la c e m e n t.
S p a n is h P eak s i n C re ta c e o u s t o Eocene tim e .
I t e l e v a t e d th e
The S p a n is h P eak s F a u lt
i s o v e rla p p e d by T e r t i a r y v o lc a n ic s e a s t o f th e G a l l a t i n R iv e r .
The
f a u l t sy stem may e x te n d a s f a r a s G a r d in e r , M ontana.
S o u th o f th e S p a n is h P e a k s , f o ld e d s e d im e n ta ry r o c k s a r e e x p o sed .
The Lower B a s in s y n c li n e p a r a l l e l s t h e S p a n ish P eak s F a u l t an d form s
m ost o f th e West F o rk b a s i n .
The Buck C reek a n t i c l i n e , a l s o tr e n d in g
J1
—5—
p a r a l l e l t o th e S p a n is h P eak s F a u l t , e x te n d s t o th e S now flake f a u l t
zone n e a r t h e b o u n d ary o f Y e llo w s to n e N a tio n a l P a r k .
M ost o f th e
ex p o sed s e d im e n ta ry r o c k s i n th e West F o rk b a s in a r e s a n d s to n e s and
s h a l e s o f C re ta c e o u s a g e .
A s t r a t i g r a p h i c d e s c r i p t i o n i s fo u n d i n
th e A p pen d ix .
A n d e s ite a n t i c l i n e i s c u t a t b o th e n d s by f a u l t s .
I t may be
r e l a t e d t o th e Lone M o u n tain i n t r u s i v e com plex.
Lone M o u n tain i s a m u l t i p l e h o r iz o n l a c c o l i t h i c i n t r u s i o n , i n
w hich A n d e s ite p o rp h y ry a l t e r n a t e s w ith s e d im e n ta ry l a y e r s .
F an ,
C e d a r, an d P io n e e r M o u n tain s t o th e s o u th w e s t a r e s i m i l a r t o Lone
M o u n tain .
A n d e s itic ' s i l l s a r e fo u n d i n th e w e s te rn p o r t i o n o f West
F o rk b a s in an d a r e p o r b a b ly r e l a t e d t o Lone M o u n tain .
$
E a s t o f th e West F o rk b a s i n , th e G a l l a t i n Range h a s b een c o v e re d
b y a p i l e o f v o lc a n ic p y r o c l a s t i c s and s e d im e n ts , w hich e x te n d s s o u th
beyond th e Y e llo w s to n e P a rk b o u n d a ry .
The s o u th e r n G a l l a t i n Range
c o n s i s t s o f f o ld e d s e d im e n ta ry r o c k s an d i n t r u s i v e s .
The s o u th e r n
M adison Range c o n s i s t s o f f o ld e d s e d im e n ta ry ro c k s an d ex p o sed b a s e ­
m ent r o c k .
Thus th e W est F o rk b a s in i s a s t r u c t u r a l low o f f o l d e d and f a u l t ­
ed s e d im e n ta r y r o c k s , w ith th e c r y s t a l l i n e S p a n ish P e a k s on th e n o r th
an d t h e m u l t i p l e i n t r u s i v e . Lone M o u n tain , on th e w e s t.
The b a s in i s
f i l l e d w ith r e l a t i v e l y n o n - r e s i s t a n t r o c k s , w h ereas th e S p a n ish P eak s
com plex i s an u p l i f t e d block" o f r e l a t i v e l y r e s i s t a n t r o c k , h en ce th e
to p o g r a p h ic d i f f e r e n c e .
PREVIOUS GEOLOGICAL WORK
E a r ly g e o lo g ic e x p l o r a t i o n i n th e r e g io n was done i n th e l a t e
1 8 0 0 's by F . V. H ayden, A. C., P e a l e , J , P e Id d in g s an d W. He Weed.
A. C. P e a le (1 8 9 3 ) a l s o mapped th e T h ree F o rk s (M ontana) Q u a d ra n g le ,
a n a r e a a b o u t th e s i z e o f Y e llo w s to n e P a rk w hich in c lu d e s th e West
F o rk a r e a .
P e a l e 's work i n th e W est F o rk re m a in e d th e o n ly work u n t i l
R. W. Swanson (1950) mapped a p a r t o f th e T h ree F o rk s Q u a d ra n g le ,
i n c lu d in g th e a r e a o f t h i s s tu d y .
H is map was u s e d a s th e b a s i s f o r
th e b e d ro c k g e o lo g y o f t h i s s tu d y .
J . A. W ilsey J r . (1948) mapped i n
th e u p p e r G a l l a t i n a r e a i n th e l a t e 1 9 4 0 's , b u t d i d n 't f i n i s h th e
w ork b e f o r e h i s d e a t h .
W. B. H a l l , now o f th e U n iv e r s it y o f Id a h o ,
c a r r i e d on W ils e y *s w ork w ith h i s own P h e D. t h e s i s ( H a l l , 1961) and
■other p u b l i c a t i o n s .
W iIs e y ' s and H a l l 's work i s c o n c e n tr a te d i n an
a r e a t,o th e s o u th o f West F o rk .
H ow ever, t h i e r w ork, and W. B. H a l l ’ s
p e r s o n a l c o n s u l t a t i o n s h av e b een a g r e a t a i d t o th e w r i t e r .
W. J . McMannis an d R. A. C hadw ick, o f M ontana S t a t e U n i v e r s i t y ,
mapped th e geology o f th e G a rn e t M ountain Q u a d ra n g le , w hich i s d i r e c t l y
e a s t o f t h e S p a n is h P eak s Q u ad ran g le an d West F o rk (McMannis and
C hadw ick, 1 9 6 4 ).
LOCAL S E W OF PROJECT AREA
SC A L E V- 150 , o o o
6 ALLAHN/ VALLEY
BUCK CREEK
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i
—9—
CLIMATE
The c l im a t e i s t y p i c a l o f a m o u n tain b a s in i n th e N o rth e rn Rocky
M o u n ta in s, w ith lo n g w in te r s an d s h o r t summers..
Summer te m p e r a tu r e s
seldom e x c e e d 85 F , an d w in te r te m p e r a tu r e s dro p w e ll belo w O F .
At
a n e l e v a t i o n o f 8 ,1 5 0 f e e t i n B ear B a s in (SW1/4 S9, T6S, R3E) th e
A p r i l I snowpack a v e ra g e d 2 2 .5 in c h e s o f w a te r from 1963 t o 1969.
In
C a r r o t B a s in , a p p r o x im a te ly 15 m ile s s o u th o f West F o rk a t 9,0 0 0 f e e t
e l e v a t i o n , th e A p r i l I snowpack a v e ra g e d 4 2 .5 in c h e s o f w a te r f o r
1967 t o 1969 (USDA and SCS, 1 9 7 0 ).
C li m a t o lo g ic a l r e c o r d s from th e F re d P e s s e l r a n c h , a b o u t 10
m ile s s o u t h e a s t o f Lone M ountain on B eav er C reek (S 1 8 , T7S, R4E) a t
6 ,7 0 0 f e e t e l e v a t i o n g iv e an i n d i c a t i o n o f th e c lim a te i n th e West
"Fork B a s in .
The f o llo w in g d a ta a r e f o r th e P e s s e l r a n c h .
J a n u a r y mean maximum te m p e r a tu r e
J a n u a ry mean minimum te m p e r a tu r e
2 9 .0 F
7 .5 F
J u l y mean maximum te m p e r a tu r e
J u l y mean minimum te m p e r a tu r e
7 8 .4 F
3 7 .9 F
A v erag e m o n th ly p r e c i p i t a t i o n
1 .6 6 "
Ja n u a ry
.7 1 "
F e b ru a ry
1 .3 9 "
March
1 .4 3 "
A p ril
May
2 .5 2 "
2 .9 6 "
Ju n e
1 .7 8 "
J u ly
A u g u st
1 .3 7 "
2 .2 7 "
S eptem ber
1 .3 9 "
O cto b er
1 .4 8 "
November
^ 3-
-
10 -
December
1 .4 1 "
A v erag e y e a r l y p r e c i p i t a t i o n
2 0 .4 3 "
(U. S . D e p t, o f Commerce, W eather B u r e a u C lim a to lo g ic a l D ata M ontana,
J a n . 1963 - J a n . 1 9 7 1 )„
FLORA AND FAUNA
The a r e a i s 90 p e r c e n t f o r e s t e d .
L odgepole P in e ( P in u s c o n t o r t a
D o u g l.) i s th e p r e s e n t d o m inant ta x o n o f th e f o r e s t o v e r s t o r y .
common a r e Englem ann S p ru ce ( P ic e a e n g e lm a n n il
A lso
B a rry ) on w et n o r th
s l o p e s . Rocky M o untain D ouglas F i r ( P se u d o ts u g a m e n z e is ii v a r . g la u c a
( B e i s s n .) F r a n c o ) , and a t h ig h a l t i t u d e s above 8,5 0 0 f e e t . Lim ber P in e
( P in u s f l e x i l i s Jam es) an d W h iteb ark P in e ( P in u s a l b i c a u l i s E n g e lm .).
Some a s p e n g ro v e s ( P o p u lu s tr e m u lo id e s M ich x ,) a r e fo u n d on lo w er
s lo p e s .
B ig s a g e b ru s h (A rte m e s ia t r i d e n t a t a N u tt.) an d Id a h o e F e sc u e
b u n c h g ra s s ( F e s tu c e id a h o e n s is Elm er) occupy th e lo w er open a r e a s
w h ile m o u n tain meadows a r e common a t h ig h e r e l e v a t i o n s .
l i n e i s a t a p p r o x im a te ly 9 ,0 0 0 f e e t .
U pper tim b e r
Some meadows occupy s i d e h i l l
c o l l u v i a l s i t e s , - b u t m ost a r e fo u n d a s s o c i a t e d w ith m ean d erin g s tre a m s
b o g s , w et a r e a s , an d f i l l e d i n p o n d s.
The f o r e s t s show e v id e n c e o f
p r e v io u s f i r e s , b u t much o f th e tim b e r i s m atu re and t h e r e i s no
e v id e n c e o f r e c e n t f i r e s .
Much o f th e lo w er a r e a h a s r e c e n t l y been
lo g g e d , an d n a t u r a l r e c o v e r y from t h i s i s e i t h e r n o t o c c u r r in g o r i s
v e r y slo w .
T h is h a s h ad a s i g n i f i c a n t im p act on th e e c o lo g y and
s u r f i c i a l s t a b i l i t y o f th e lo g g e d a r e a s .
The s tu d y a r e a h a s a n a t u r a l f a u n a l p o p u la tio n r a n g in g from
i n s e c t s t o b ig gam e. I n e a r l y t o m id-sum m er, m o s q u ito s im pede o u td o o r .
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frogs:,',toad s> -'garter shakes-^'m lc e ,r s q u ir r e ls ,- -chipmunks, . 'cdneysp:'p'or—
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cupinef and 1S k iik s ,' B ig game "animals in c lu d e deer^- m oosey.e lk , mountain
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s h e e p m o u n t a i n g . o a t s a n d b e a r , - O ld beav er, c u t t i n g s w ere fo u n d ,/ b u t . .
- "r
t h e r e w as n o e v id e n c e o f . c u r r e n t b e a v e r o c c u p a tio n , W hile t h e ■c l e a r — ■ ■te-T;;
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The W est F o rk b a s i n i s c u r r e n t l y u s e d f o r lo g g i n g , c a t t l e g r a z — T-
, >
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i n g , f i s h i n g , - r e c r e a t i o n an d dude r a n c h h o rs e b a c k t r i p s .
P ro p o se d
‘ -.<■ ' - yT- > V:- 'TL. T---,.V
u s e b y B ig ., SkyiZof' M ontana, c a l l s f o r t h e c o n s t r u c t i o n o f a .'paved a c c e s s . -T'-T
I.',- !
Tv ■
r o a d , - ' s k i. -J i f t s a n d t r a i l s on A n d e s ite a n d Lone. M o u n t a i n s s k i 'V :/; V l v v . O s-*iy
-
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v i l l a g e a t 'tiie f o o t o f Lohe M o untain C S30, 'T 6S , R3E)-, p r i v a t e h o u s e X -..-'/N tA l-..
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an d condom inium s i t e s a n d . a s s o c i a t e d sew age an d w a te r d ev elo p m en t^ ' A . . , vTt - - .
summer village i s t o b e situated b elo w (east) t h e WtiterrS study area...
SCOPE AND METHOD- OF STUDY
'
"
......
F i e l d s tu d y was p a r t i a l l y fu n d e d b y a g r a n t fro m th e N a tio n a l
""
-1 2 S c ie n c e F o u n d a tio n t o th e C e n te r f o r E n v iro n m e n ta l S tu d ie s a t M ontana
S ta te U n iv e rs ity ,
The g r a n t s u p p o r ts an i n t e r d i s c i p l i n a r y s tu d y o f
th e West F o rk b a s in an d G a l l a t i n Canyon w hich w i l l e s t a b l i s h e n v iro n ­
m e n ta l b a s e l i n e s f o r co m p ariso n a s th e b a s i n i s f u r t h e r d e v e lo p e d .
The g r a n t p r o j e c t i s t i t l e d The Im p act o f a L arg e R e c r e a ti o n a l D evel­
opment on a S e m ip r im itiv e E n v iro n m e n t.
P r o f e s s o r Jo h n M ontagne,
M ontana S t a t e U n i v e r s i t y , was th e p r i n c i p a l g e o lo g ic i n v e s t i g a t o r f o r
th e p r o j e c t .
A lan Kehew* H e la in e W alsh and th e w r i t e r j o i n t l y s t u d i e d
th e W est F o rk b a s in u n d e r th e g u id a n c e o f P r o f e s s o r M ontagne1' Kehew
w orked t o th e s o u th an d W alsh w orked t o th e s o u th e a s t o f th e w r i t e r ’ s
s tu d y a r e a ( s e e c r e d i t map on P l a t e I ) .
F i e l d work was co m p le te d d u r in g A u g u st and S e p te m b e r, 1970.
U. S. F o r e s t S e r v ic e S e r ie s ElO (p h o to g ra p h e d i n 1961-1962) a r e a l
p h o to g ra p h s ( s c a l e A i n . p e r m ile ) and th e U, S , G e o lo g ic a l S urvey
15 M inute S p a n is h P eak s Q u a d ran g le w ere u s e d f o r f i e l d m apping.
W orking fro m a b a s e camp a t th e u p p e r ( s k i ) v i l l a g e , f o o t f i e l d
t r a v e r s e s s e r v e d t o c o v e r th e map a r e a .
S e v e r a l days w ere s p e n t w ith
A lan Kehew an d H e la in e W alsh on p ro b lem s o f m u tu al i n t e r e s t .
The
w r i t e r a l s o h a d v e r y h e l p f u l c o n v e r s a tio n s w ith P r o f e s s o r s C. C.
B r a d le y , W. B, H a ll an d J . M ontagne, who v i s i t e d i n th e f i e l d .
Jo e
A rm stro n g o f th e M ontana Highway D e p a rtm e n t, Sam Sm eding, W. C.
V is s c h e r o f N o rth e rn T e s t in g , and p e r s o n n e l .o f Van Kyken D r i l l i n g
Company a l s o p r o v id e d .c o n s u l ta t io n i n .th e f i e l d .
-1 3 P r i o r t o t h i s p r o j e c t , th e w r i t e r g a in e d p r a c t i c a l e x p e r ie n c e i n
Q u a te rn a ry g e o lo g y m apping o f s i m i l a r a r e a s i n Y e llo w s to n e N a tio n a l
P a rk u n d e r H. A. W aldrop, K„ L, P ie r c e an d G. M. Richmond o f th e U. S.
G e o lo g ic a l S u rv e y .
DEFINITION OF ENVIRONMENTAL GEOLOGY
The te rm , e n v iro n m e n ta l g e o lo g y , i s new , and f o r m a l d e f i n i t i o n s
a re n o t a v a ila b le .
H ow ever, i t i s n e c e s s a r y t o d e f in e th e term a s i t
a p p lie s to t h i s r e p o r t.
E n v iro n m e n ta l g e o lo g y i s th e s tu d y o f g e o l o g i­
c a l f e a t u r e s r e l a t e d t o m a n 's u s e o f h i s en v iro n m en t an d th e r e l a t i o n
o f g e o lo g y t o o th e r f e a t u r e s o f th e n a t u r a l e n v iro n m e n t,
A g e o l o g ic a l
s e t t i n g may p r o v id e m a t e r i a l s f o r Ktant S u s e o r s e r v e a s a s i t e f o r
m a n 's a c t i v i t i e s .
G eology may d i c t a t e th e a v a i l a b i l i t y o f m a t e r i a l s
o r th e t e c h n i c a l and econom ic f e a s i b i l i t y o f a p ro p o s e d s i t e u s e .
G eology i n f l u e n c e s c h a r a c t e r i s t i c s o f th e n a t u r a l e n v iro n m e n t, o f w hich
man i s a p a r t .
G e o lo g ic a l know ledge o f th e s e r e l a t i o n s h i p s may h e lp
man d e f in e an d u n d e r s ta n d h i s im p a c t on th e e n v iro n m e n t.
B ecause
many f e a t u r e s o f th e la n d s c a p e a r e young g e o l o g i c a l l y , s tu d y o f th e
Q u a te rn a ry h i s t o r y and s u r f i c i a l g e o lo g y i s an im p o r ta n t p a r t of
e n v iro n m e n ta l g e o lo g y .
E n v ir c .-nental g e o lo g y in th e W est F o rk B a sin i s c o n c e rn e d w ith
la n d u s e f o r r e c r e a t i o n , r e s id e n c e an d r e s o u r c e h a r v e s t ( t i m b e r ) ,
It
a l s o d e a ls w ith g e o l o g i c a l i n f l u e n c e s on th e n a t u r a l e n v iro n m en t and
-1 4 th e r o l e o f g e o l o g i c a l h i s t o r y i n sh a p in g th e p r e s e n t la n d s c a p e .
OBJECTIVES OF STUDY
The o b j e c t i v e s o f t h i s s tu d y a r e tw o fo ld ;
1.
Map an d i n t e r p r e t Q u a te rn a ry an d s u r f i c i a l g eo lo g y
an d c o r r e l a t e i t w ith o th e r work i n th e Rocky M o u n tain s.
2.
F in d an d s tu d y g e o l o g i c a l a s p e c t s o f th e a r e a w hich may
in f l u e n c e man’ s u s e of th e en v iro n m e n t i n t h i s or
s im ila r a re a s .
^
QUATERNARY GLACIAL AND SURFICIAL GEOLOGY
-1 6 INTRODUCTION
M apping th e s u r f i c i a l an d g l a c i a l g e o lo g y co m p rised th e b u lk o f
th e f i e l d work f o r t h i s s tu d y .
C o r r e la te d w ith th e b e d ro c k g e o lo g y ,
s u r f i c i a l f e a t u r e s a r e th e k e y s t o th e Q u a te rn a ry h i s t o r y and e n v iro n ­
m e n ta l g e o lo g y o f th e a r e a .
The f o llo w in g c h a p te r l i s t s c r i t e r i a by
w hich g l a c i a l f e a t u r e s a r e mapped an d d i s t i n g u i s h e d fro m one a n o th e r ,
d e s c r ib e s t h e s u r f i c i a l f e a t u r e s a s mapped on P l a t e I , and o u t l i n e s
p o s tu la te d causes of la n d s lid in g ,
The g l a c i a t i o n s and ro c k g l a c i e r s
o f N o rth F o r k , B eeh iv e C re e k , M o o n lig h t C reek an d Lone M ountain a r e
d e s c r ib e d , a s w e ll a s a s s o c i a t e d l a n d s l i d i n g .
R o c k f a l ls , snow a v a ­
la n c h e s an d d e p o s i t s o f v o lc a n ic t u f f ( a s s o c i a t e d w ith t i l l )
a re a ls o
d e s c r ib e d .
The r e a d e r c o n c e rn e d o n ly w ith e n v iro n m e n ta l i m p l i c a t i o n s " o f
t h i s s tu d y may w ish t o s k ip t h e f i r s t p a r t o f t h i s s e c t i o n an d s t a r t
w i t h . t h e p a r t on r o c k g l a c i e r s .
QUATERNARY GLACIAL CORRELATIONS IN THE ROCKY MOUNTAINS
The c o n c e p t o f m u l t i p l e g l a c i a t i o n s d u rin g th e Q u a te rn a ry i s w e ll
a c c e p te d .
One o f t h e p r i n c i p a l o b j e c t i v e s o f th e Q u a te rn a ry g e o l o g i s t
i s t o d i s t i n g u i s h b etw een g l a c i a l d e p o s i t s o f d i f f e r e n t a g e s .
Work in
t h e Wind R iv e r M o u n tain s o f Wyoming by B la c k w e ld e r (1915) an d Richmond
( 1 9 6 5 ) , among o t h e r s , i s u s e d a s th e b a s i s f o r such c o r r e l a t i o n work
i n th e Rocky M o u n ta in s ,
Age a p p ro x im a tio n s a r e s u b j e c t t o change a s '
—17—
w ork i s d o n e.
F ig u r e 3 i s a b s t r a c t e d fro m a c o r r e l a ti o n " c h a r t by
Richmond (1 9 6 5 ) # an d shows a p r e s e n t l y a c c e p te d c l a s s i f i c a t i o n of
g l a c i a t i o n s i n t h e Rocky M o u n ta in s«
The Rocky M o u n tain W isco n sin g l a c i a t i o n s hav e o b l i t e r a t e d much
o f th e e v id e n c e f o r e a r l i e r g l a c i a t i o n s .
Such e v id e n c e when fo u n d i s
o f te n s im p ly c l a s s i f i e d a s p re -W is c o n s in o r p r e - B u l l L ak e.
T hese
g l a c i a t i o n s w ere a p p a r e n tly more e x t e n s i v e th a n m ost W isc o n sin g l a c i a ­
t i o n s , w h ich w ere commonly c ir q u e an d v a l l e y g l a c i e r s w ith some l o c a l
ic e cap s.
I n th e Rocky M o u n ta in s, th e W isco n sin g l a c i a t i o n i s com­
m only d iv id e d i n t o t h e B u ll Lake an d P in e d a le s ta g e s .
B ased on h i s Wind R iv e r work an d o th e r e x p e r ie n c e , Richmond (1965)
h a s d e v e lo p e d some o f th e f o llo w in g c r i t e r i a a s c h a r a c t e r i s t i c s of
Rocky M o u n tain g l a c i a l d e p o s i t s an d t h e i r i n t e r g l a c i a l s o i l s :
P re -W is c o n s in
Rem nants o f h i g h l y w e a th e re d s h e e t t i l l o f te n
fo u n d up t o 1 ,0 0 0 f t . above canyon f l o o r s and
u s u a l l y above an d beyond th e l i m i t s o f B u ll
Lake t i l l .
E v id en ce f o r t h r e e p re -W is c o n s in
g l a c i a t i o n s h a s b een fo u n d .
B u ll Lake
Smooth b u lk y su b d u e^ m o r a in e s , f i l l e d k e t t l e s ,
s u r f a c e b o u ld e r s o f te n b u r ie d an d w e a th e re d , up
t o t h r e e s h a d e s n o te d .
S o i l d e v e lo p e d on B u ll Lake d e p o s i t s
M ature z o n a l s o i l , B h o r i ­
zon r e d brown t o brown (5YR t o 7 .5 YR), 3 t o 1 ,2
m e te r s t h i c k , y e llo w brown (10YR) i n n o r t h ,
i l l u v i a t e d c l a y , m o d e ra te ly d e v e lo p e d s u b a n g u la r
b lo c k y s t r u c t u r e , P e d a lf e r - P e d o c a l b o u n d ary a t
7,0 0 0 f t . i n c e n t r a l Wyoming an d 5 ,2 0 0 f t , in
n o r th e r n M ontana.
GLACIATION IN THi ROCKT MOUNTAINS
FROM RICHM OND W S
XEARS B P
2000
4000
G LACIATIONS 4*INTERGLACtATlONS
NEOGLACtAL
T EtIPlE LhKL STADE
6000
R ooo
IOO OO
12000
14000 '
ifo o o o r
lS o o o i
20000
22000
STADES
GANNETT PEAK STADE
IN T E R ST A D E
A lT lW m A E INTERVAL
W ISCONSIN
PINEDALE
GLACIATION
LATE STADE
INTERSTADE
CUDDLE STADE
24 O 0 0 2 b OOO
INTERSTATE
2 %0 0 0
50 0 00
EARLY STADE
5 2 O OQ
5 4 0 OO
IN T E R G L A C IA L
Sbooo
58000 _
40000
42ooo
BULL LAKE GLACIATION
44000
INTERGLACIAL_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
PRE-WISCONSIN
PRE-BULL LAKE. CbLAClATTOt-J5**OiTERGLAHATIOrJS
S a c AGAviEA R idge 1Cedar ridge ,whshame P o in t
FIGURE 3
-1 9 P in e d a le
M o rain es a r e s t e e p , i r r e g u l a r an d f r e s h in
a p p e a r a n c e , k e t t l e s a r e u n f i l l e d , s u r f a c e b o u ld ­
e r s show l i t t l e w e a th e r in g . The m o ra in e s a r e
u s u a l l y s m a lle r an d l i e up v a l l e y fro m th e B u ll
Lake m o ra in e s . T h ree s ta d e s a r e known, th e
e a r l y and m id d le s ta d e b e in g o f a b o u t th e same
e x t e n t . The l a t e s ta d e o f te n d id n o t e x te n d o u t
o f th e s o u rc e c i r q u e .
S o i l s on P in e d a le d e p o s i t s
Im m ature z o n a l s o i l , a h o r iz o n 1 0 15 i n , t h i c k , v e r y l i t t l e c l a y i l l u v i a t i o n , weak
t o m o d e ra te s t r u c t u r e , B h o r iz o n y e llo w is h brown
(IOYR).
Tem ple Lake
F r e s h m o ra in e s 1 8 -5 5 f t , h ig h w ith h ig h a l t i t u d e
v e g e t a t i o n an d weak a z o n a l s o i l , o f te n ,5 t o
1 ,5 m ile s from th e c ir q u e h e a d w a ll,
G a n n e tt P eak
F r e s h ro u g h m o ra in e s w ith no s o i l an d o n ly
p io n e e r p l a n t s . The m o rain e o f 1850 a p p e a rs t o
-be m o st e x t e n s i v e o f s e v e r a l a d v a n c e s w ith in
t h e p a s t fe w c e n t u r i e s .
USE OF SOILS IN AGE CORRELATIONS
B ecause s o i l d ev elo p m en t i s r e l a t e d t o tim e , a s w e ll a s t o th e
»
f a c t o r s o f p a r e n t m a t e r i a l , c l i m a t e , r e l i e f an d o rg a n is m s , an d s in c e
g l a c i a t i o n s w ere f o llo w e d by warm p e r io d s o f s o i l f o r m a tio n , s o i l s
d e v e lo p e d on Q u a te rn a ry d e p o s it s can be a g r e a t h e lp i n a g e c o r r e l a ­
tio n .
M o rris o n (1965) h a s p ro p o s e d th e name "G e o so l" t o d e s c r ib e
a n c ie n t b u t p re se rv e d s o i l s u sed as S o il- S tra tig r a p h ic u n it s .
S p e c ifi­
c a l l y , g iv e n s i m i l a r f a c t o r s o f p a r e n t m a t e r i a l , c l i m a t e , r e l i e f and
o rg a n is m s , a s o i l p r o f i l e d e v e lo p e d on B u ll Lake t i l l , w hich was ex­
p o s e d t o th e p o s t - B u l l Lake I n t e r g l a c i a l c lim a te f o r th o u s a n d s of
y e a r s , s h o u ld show a h ig h e r d e g re e o f dev elo p m en t th a n a p r o f i l e
-2 0 d e v e lo p e d on y o u n g e r P in e d a le t i l l ,
f l u c t i o n o r o th e r e r o s i o n .
i f n o t d e s tr o y e d by P in e d a le s o l i -
P r o f i l e c h a r a c t e r i s t i c s in c lu d e d ep th t o
th e c a lc iu m c a r b o n a te h o r iz o n an d dev elo p m en t o f an a r g i l l i e B h o r iz o n
( c l a y i l l u v i a t i o n ) w ith c h a r a c t e r i s t i c p r o p e r t i e s o f t e x t u r e and
s t r u c t u r a l d ev elo p m en t.
ag e o f g l a c i a l t i l l s .
I n t h i s s tu d y , s o i l s w ere u s e d t o c o n firm th e
The m ost u s e f u l an d e a s i l y r e c o g n iz e d c h a r a c ­
t e r i s t i c s w ere d e p th t o u n a l t e r e d p a r e n t m a t e r i a l an d th e e x i s t e n c e o f
an a r g i l l i c B h o r iz o n .
Som etim es t h i s m ethod o f age d i s t i n c t i o n i s an
e x p e d ie n t an d u s e f u l , t o o l .
H ow ever, o c c a s i o n a ll y d i f f e r e n c e s a r e n o t
a p p a r e n t o r a r e c o n f u s in g .
F ig u r e 4 d iag ram s t y p i c a l s o i l p r o f i l e s
d e v e lo p e d on B u ll Lake and P in e d a le t i l l s .
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X
-2 2 PRE-WISCONSIN GLACIATION IN WEST FORK
P a tc h e s o f h ig h l e v e l t o p o g r a p h i c a l ly i s o l a t e d t i l l im p ly t h a t
th e a r e a was a lm o s t c o m p le te ly i c e c o v e re d a t one tim e .
However, th e
m ost o b v io u s g l a c i a t i o n s c o n s i s t e d o f m o u n tain v a l l e y g l a c i e r s .
By
r e g i o n a l c o r r e l a t i o n w ith f e a t u r e s i n th e Wind R iv e r M o u n tain s o f
Wyoming, ( B la c k w e ld e r, 1915; Richm ond, 1 9 6 5 ), th e s e f e a t u r e s a r e o f
W isco n sin and r e c e n t a g e .
P re -W is c o n s in g l a c i a l f e a t u r e s have been
l a r g e l y o b l i t e r a t e d by th e e x te n s iv e W isco n sin g l a c i a t i o n s i n th e
are a .
A d d iti o n a l in f o r m a tio n on th e p re -W is c o n s in g l a c i a t i o n in th e
West F o rk w i l l b e g iv e n i n s u b s e q u e n t p a g e s . ' D e p o s its o f t h i s g l a c i a ­
t i o n a r e a s s o c i a t e d w ith a w eld ed t u f f .
NORTH FORK BULL LAKE GLACIATION AND RELATED LANDSLIDING
F ig u r e 5 d ia g ra m s g l a c i a l f e a t u r e s i n N o rth F o rk i
The l a r g e s t o f th e W isco n sin g l a c i a t i o n s i n th e N o rth F o rk d r a i n ­
ag e te r m in a te d b elo w th e j u n c t i o n o f th e M iddle and N o rth F o rk s i n an
a r e a mapped by W alsh (1 9 7 1 ).
The te r m in a l p o s i t i o n i s a p p ro x im a te d by
a, l a r g e sm ooth end m o rain e b etw een Lone M ountain Ranch an d C r a i l Ranch
(S 2 2 , T6S, R 3E)„
A p p ro x im a te ly t h r e e m ile s above th e te r m in a l p o s i ­
t i o n , a t an e l e v a t i o n o f 8,0 0 0 f t . , th e l a t e r a l m o ra in e c o n s i s t s o f a t
l e a s t 100 f t .
o f t i l l c a p p in g th e b e d ro c k r i d g e c o r e .
m a n tle d w ith t i l l on b o th s i d e s .
The r i d g e i s
. .
A s m a ll te r m in a l m o rain e d i r e c t l y n o r th o f th e Lone M ountain Ranch
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-2 4 (SW1/4 S26, T6S, R 3E ), w hich h a s a ro u n d ed m a tu re form s i m i l a r t o t h a t
o f th e m ain te r m in a l m o ra in e , i n d i c a t e s a t l e a s t one s m a lle r s ta d e o f
B u ll Lake g l a c i a t i o n .
A s o i l on t i l l j u s t above t h i s te rm in u s i s
s i m i l a r t o s o i l on th e m ain te rm in a l, m o ra in e .
A B u ll Lake s o i l p ro ­
f i l e on th e m ain te r m in a l m o rain e i s i l l u s t r a t e d an d d e s c rib e d , in
F ig u r e s 6a an d 6b.
On b o th s i d e s o f th e w e st r id g e o f th e N orth F o rk can y o n , unmod­
i f i e d to p o g ra p h y d e v e lo p e d i n t i l l i s c h a r a c t e r i s t i c .
, The to p o g ra p h y
c o n s i s t s o f hummocky m o r a in a l ty p e fo rm s and u n f i l l e d d e p r e s s io n .
S c a rp s and slum p b lo c k s c h a r a c t e r i s t i c o f l a n d s l i d i n g a r e p r e s e n t .
C re ta c e o u s s h a le i s ex p o sed i n p la c e s ' u n d e rn e a th th e t i l l and i s a
b a s i c f a c t o r i n th e s l i d i n g .
The u p p e r s c a r p o f one o f th e s l i d e s
(S 2 1 , T6S, R3E) c u t s th e h ig h l a t e r a l m o rain e a t 8,000 f t . and ex p o ses
i n th e m id s e c tio n o f th e s l i d e some 300 v e r t i c a l f e e t below and t o
th e e a s t .
F ig u r e 7 shows th e M iddle F o rk lo g g in g ro a d c u t t i n g th ro u g h a
l a r g e s l i d e a r e a on t h e w e s t s id e o f th e N o rth F o rk r i d g e a p p r o x i­
m a te ly 1 .2 m ile s above th e N o rth F o rk r o a d c r o s s in g .
The s l i d e i s
lo c a t e d i n S27, T6S, R3E and h a s a s h a rp u p p e r s c a r p an d v e r y hummocky
f r e s h to p o g ra p h y .
I t i s c o v e re d w ith 5 to 10 f e e t o f t i l l and v e ry
l i t t l e b e d ro c k i s e x p o s e d .
The r o a d c u t p i c t u r e d i n F ig u r e 7 ex p o ses
a b o u t 15 f e e t o f w hat i s th o u g h t t o be C re ta c e o u s T h erm o p o lic S h a le ,
w hich i s p r e s e n t l y a c t i v e l y s l i d i n g .
The new r o a d s u rv e y e d -b y th e
F ig u re 6 a . S o il d e v e lo p e d on B u ll Lake t i l l n o r th o f
C r a i l R anch. Note b la c k m o llic e p ip e d o n , brown B2t
h o r iz o n and y e llo w is h p a r e n t m a t e r i a l w hich i s t i l l
o f c r y s t a l l i n e ro c k s from B ear B a s in .
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ELEVATION G4DG-(o5C)OEEE.T
F ig u re 7 . L a n d s lid e r e a c t i v a t e d by lo g g in g r o a d . I t i s
d e v e lo p e d i n C re ta c e o u s T h erm o p o lis S h a le and m a n tle d
w ith B u ll Lake g l a c i a l t i l l .
- 2
8
-
M ontana Highway D ep t, w i l l a v o id t h i s u n s t a b l e s l i d e a r e a (J o e Arm­
s t r o n g , M ont. Highway D ep t. G e o lo g is t, P e r s o n a l co m m u n icatio n , A u g u st,
1 9 7 0 ).
I n summary, th e N o rth F o rk B u ll Lake g l a c i e r was o f s i g n i f i c a n t
s i z e , te r m in a t in g a b o u t 9 m ile s from th e p a r e n t c i r q u e i n B ear B a s in .
I t was f e d fro m th e m ain e a s t f a c in g c i r q u e , th e u p p e r v a l l e y w a l l s ,
and th e h a n g in g c i r q u e v a l l e y t o th e w e st o f B ear B a s in (S 5 , 8 , T6S,
R 3E ).
Midway t o th e te r m in a l p o s i t i o n , th e i c e was a t l e a s t 600 f e e t
th ic k .
T i l l , c o n s i s t i n g - o f c r y s t a l l i n e m a t e r i a l , s p i l l e d o v er th e w est
r i d g e o f th e N o rth F o rk canyon and c o v e re d th e h i l l s i d e . • The t i l l
o v e rb u rd e n , d e p o s ite d i n e a r l y W isco n sin tim e ( B u ll L a k e ), -covered th e
C re ta c e o u s s a n d s to n e s an d s h a l e s .
D u rin g th e l a t e W isco n sin ( P in e d a le )
g l a c i a t i o n and d e g l a c i a t i o n , th e C re ta c e o u s b e d ro c k became u n s t a b l e
an d s l i d .
T h is was pfSrbably due t o in c r e a s e d f l u v i a l a c t i v i t y and t h e
w e ig h t o f th e t i l l o v e rb u rd e n .
The s l i d i n g was e v i d e n t l y n o t c a t a s ­
t r o p h i c , b u t b eh av ed a s a slo w flo w .
day i n some a r e a s .
I t h a s c o n tin u e d t o th e p r e s e n t
The s l i d e s u s u a l l y h av e w e ll d e f in e d u p p e r b r e a k ­
away s c a r p s and c h a r a c t e r i s t i c f r e s h lumpy to p o g ra p h y .
T h is t i l l -
c o v e re d to p o g ra p h y a p p e a rs t o be P in e d a le g l a c i a l d e p o s i t s u n t i l i t i s
re c o g n iz e d a s a l a n d s l i d e .
The w r i t e r a s s ig n s th e above d e s c r ib e d g l a c i a t i o n s an ag e o f B u ll
Lake o r e a r l y W isco n sin f o r th e f o llo w in g r e a s o n s :
f
-2 9 1.
Form
The t i l l h a s th e c l a s s i c ro u n d ed m a tu re B u ll Lake
fo rm , w ith few u n f i l l e d d e p r e s s io n s and la c k o f
f r e s h , lumpy to p o g ra p h y . Most o f th e b o u ld e rs a r e
p a r t l y b u r ie d .
2.
S o ils
S o i l p r o f i l e s on t h i s t i l l a r e w e ll d e v e lo p e d w ith
r e g a r d t o B h o r iz o n c l a y i l l u v i a t i o n , and a r e much
d e e p e r th a n P in e d a le s o i l s w hich o f t e n o n ly hav e
A-C h o r iz o n a tio n .
3.
P o s itio n
T h is t i l l l i e s below any o th e r m a jo r m o ra in e s in
th e N o rth F o rk th u s i t m ust be o ld e r th a n th o s e
w hich a r e a s s ig n e d an e a r l y W isco n sin ( P in e d a le )
a g e . I t a l s o d id n o t hav e th e g r e a t e x t e n t o f a t
l e a s t one p r e v io u s g l a c i a t i o n i n th e a r e a ( p r e W isco n sin ) .
4.
S lid i n g
The s l i d i n g a c t i v i t y was p a r t i a l l y th e r e s u l t of
B u ll Lake t i l l r e s t i n g on s a n d s to n e an d s h a le
d u r in g P in e d a le f l u v i a l a c t i v i t y .
One d o es n o t
f i n d such l a r g e s c a l e s l i d i n g o c c u r r in g i n th e
P in e d a le t i l l s o f th e a r e a . T h u s, t i l l o f B u ll
Lake ag e i s a s s o c i a t e d w ith P in e d a le ag e s l i d i n g .
NORTH FORK PINEDALE GLACIATION
A t l e a s t t h r e e P in e d a le g l a c i e r s o c c u p ie d th e N o rth F o rk can y o n ,
b u t w ere s m a lle r th a n th e B u ll Lake g l a c i e r s .
E v id en ce f o r P in e d a le g l a c i a t i o n i n th e N o rth F o rk i s fo u n d i n
S 22, T6S, R3E.
H e re , f r e s h lumpy t i l l w ith u n f i l l e d k e t t l e s l i e s on
th e canyon f l o o r .
T h is t i l l dammed N o rth F o rk .
th e dam fo rm s a meadow.
A l l u v i a l f i l l b e h in d
The s o i l p r o f i l e on t h i s t i l l d i f f e r s from a
p r o f i l e on B u ll Lake t i l l a s h o r t d is ta n c e down th e can y o n .
The two
p r o f i l e s a r e d ia g ra m ed i n F ig u r e 8.
No l a t e r a l m o ra in e s h av e b een fo u n d d e sc e n d in g th e canyon w a lls t o
B U L llA K E A m p m L E SOILS ALONG NORTH FORK
+ 2 '~ 0 " DUFF
As O"- is"
N o N c m c A B it
CLAY ACCUMULATION
C
TILL PARENT
flA T m A l
'D
O
BOTH SOILS AtRE LOCATED ON TTLL OF W STALLM E ROCLS 3U 5T
A50NE GREEK LEVEL AT & L ^ f\T \O N T Z o o '- 7 4 0 0 ' - 5 JLZt #
T b S R a E - VEGETATION 15 VDOStPOLE P M E P O R tST
EtGViRV: %
-3 1 t h i s p o i n t ; h o w ev er, th e w e st canyon w a ll i s a s l i d e a t t h i s l o c a t i o n
and th e e a s t w a ll i s a b e d ro c k c l i f f w ith t a l u s and a l l u v i a l d e b r i s .
T h is p o s i t i o n a p p e a r s t o m ark th e f u r t h e s t e x t e n t o f th e P in e d a le
f i r s t s t a d e , w hich was th e m ost e x t e n s i v e o f th e t h r e e P in e d a le
s ta d e s .
A p o s s i b l e te r m i n a l p o s i t i o n o f t h e seco n d P in e d a le s ta d e i s l o ­
c a t e d i n 3 1 6 , 1 6 3 , R3E, w here th e N o rth F o rk canyon makes a sh a rp
bend.
A l a r g e t i l l p lu g o c c u p ie s th e v a l l e y b o tto m h e r e an d i s a s s o ­
c i a t e d w ith a kame t e r r a c e w hich e x te n d s down can y o n .
P o s s i b le rem ­
n a n ts o f l a t e r a l m o ra in e s a p p e a r t o be d e sc e n d in g t o t h i s p o s i t i o n on
b o th s i d e s o f th e c r e e k .
The e x a c t t e r m i n a l . p o s i t i o n can n o t be de­
te rm in e d b e c a u se o f s l i d i n g on th e w e st s id e o f th e can y o n .
F u r t h e r e v id e n c e f o r a P in e d a le v a l l e y g l a c i e r te rm in u s h e r e i s
s e e n i n th e re m n a n ts o f l a t e r a l m o ra in e s h ig h above an d up th e c r e e k .
They i n c l i n e dow nstream a t a n g le s o f 20 d e g r e e s .
P r o j e c t i o n o f th e s e
fo rm s dow nstream le a d s t o th e te r m in a l p o s i t i o n d e s c r ib e d ab o v e.
T h is
te r m in a l p o s i t i o n i s j u s t belo w a P in e d a le (b a s e d on f r e s h n e s s ) ro c k
g la c ie r and a l l u v i a l fa n .
T hese two f e a t u r e s , on o p p o s ite s id e s o f
th e c a n y o n , m eet a t th e c r e e k .
They a r e f e a t u r e s o f th e t h i r d s ta d e
o f P in e d a le g l a c i a t i o n w hich o c c u r r e d a f t e r th e seco n d ,s ta d e , w hich
te r m in a te d j u s t ' b elo w .
The t h i r d s ta d e o f th e N o rth F o rk P in e d a le g l a c i a t i o n i s r e p r e ­
s e n te d h ig h i n B ear B a s in , th e p a r e n t c i r q u e .
In B ear B a s in , w hich i s
F ig u r e 9 ,
D iagram o f an e a s t f a c i n g c ir q u e c a rv e d fro m a s o u th
fa c in g b a s in .
p re d o m in a n tly s o u th f a c i n g , th e m ain ic q a c c u m u la tio n was i n a s u b s i d i ­
a ry e a s t fa c in g c irq u e .
T h is i s t y p i c a l o f su ch s o u th f a c i n g accumu­
l a t i o n b a s i n s an d r e s u l t s i n e a s t f a c i n g c i r q u e s a t th e h e a d s o f th e
b a s in s .
M o rain es o f th e t h i r d s ta d e a r e fo u n d on th e f l o o r o f B ear B a s in ,
h a v in g b a r e l y a d v an c ed o u t o f th e s o u rc e c i r q u e .
They a p p e a r v e ry
f r e s h w ith lumpy to p o g ra p h y , u n f i l l e d d e p r e s s io n s an d b o u ld e r s on th e
su rfa c e .
V e g e ta tio n i s w e ll e s t a b l i s h e d , b u t a minimum o f s o i l fo rm a \
t i o n h a s ta k e n p l a c e .
Tlae s o i l s w ere n o t c l o s e l y exam in ed .
T h is s m a ll
v a l l e y g l a c i e r was n e a r l y .5 m ile lo n g and 200-300 f e e t i n maximum
th ic k n e s s .
NE03IACIATI0N
Above th e P in e d a le t h i r d s ta d e te r m in a l p o s i t i o n a r e s m a ll w e ll
-3 3 d e f in e d m o ra in e s o f a more r e c e n t g l a c i a t i o n w hich a r e c o r r e l a t e d w ith
th e Temple Lake s ta d e o f N e o g la c ia tio n .
These m o ra in e s a r e v e ry f r e s h ,
w ith s h a rp w e ll d e f in e d fo rm , and h av e o n ly a t h i n g r a s s c o v e r .
T h ese
e a s t f a c i n g g l a c i e r s w ere up t o 1 /4 m ile i n le n g th and p e rh a p s 100 f e e t
th ic k .
Two su ch m o ra in e s h av e b een mapped i n th e u p p e r c ir q u e o f B ear
B a s in .
S em i-p erm an en t snow f i e l d s occupy th e b a c k s lo p e a r e a s o f th e s e
m o ra in e s .
A d d iti o n a l s tu d y m ig h t r e v e a l e v id e n c e f o r th e G a n n e tt
P eak s ta d e in t h i s a r e a .
GLACIATION IN THE HANGING VALLEY
The h a n g in g v a l l e y i n S5 an d 8 , T6S, R3E, w hich d r a in s from th e
w e s t i n t o N o rth F o rk , c o n t r i b u t e d B u ll Lake an d P in e d a le i c e t o th e
N o rth F o rk g l a c i e r s .
S u g g e s tio n s o f a P in e d a le t h i r d s ta d e te r m in a l
p o s i t i o n h a v e b e e n fo u n d i n th e lo w e r p a r t o f t h i s v a l l e y , and g round
m o ra in e i s a b u n d a n t i n th e u p p e r p a r t o f th e v a l l e y .
S e v e r a l sm a ll
la k e s occupy g l a c i a l l y gouged f l a t a r e a s i n th e b a s in f l o o r .
T h is h a n g in g v a l l e y a l s o f a c e s t o th e s o u th l i k e B ear B a s in ,
T h ere is - e v id e n c e t h a t m o st o f th e i c e a c c u m u la te d on th e e a s t f a c in g
p a r t o f th e c i r q u e .
Midway up th e v a l l e y on th e w e st s id e ( e a s t
e x p o s u re ) a r e f r e s h m o r a in a l form s w hich b a r e l y r e a c h th e b a s in f l o o r .
They a r e a r c u a t e fo r m s , co n cav e to w a rd th e h i l l s i d e , 50 f e e t i n h e i g h t ,
and w ith b a c k s lo p e d e p r e s s io n s o f 15 f e e t .
They a r e composed o f l a r g e
(5 f e e t d ia m e te r ) g n e i s s i c b o u ld e r s , w ith a p o s s i b l e m a tr ix o f f i n e r
-3 4 m a t e r i a l w ith i n .
The r o c k s a r e w e ll lic h e n e d , b u t th e f i n e g r a in e d
m a t e r i a l b etw een th e r o c k s h a s o n ly a s p a r s e g r a s s c o v e r .
On th e
b a s i s o f f r e s h fo rm and p o s i t i o n above th e P in e d a le t i l l , , th e f e a ­
t u r e s a r e '" a s s ig n e d t o th e Temple Lake s t a d e .
g l a c i a l m o ra in e s o r p r o - t a l u s r a m p a r ts .
They may be e i t h e r t r u e
T h ere i s no d o u b t t h a t th e y
w ere c a u s e d by snow an d i c e e i t h e r a s p erm a n en t snow f i e l d s o r a s
g l a c i a l i c e d u r in g th e Temple Lake s ta d e o f N e o g la c ia tio n .•
BEEHIVE CREEK GLACIATIONS AND RELATED LANDSLIDES
F e a t u r e s i n B e e h iv e C reek a r e d iag ram ed and i l l u s t r a t e d in F ig u r e s
IOa and 1 0 b .
g la c ie rs .
B eeh iv e C reek was o c c u p ie d b y B u ll Lake and P in e d a le
D u rin g t h e P in e d a le d e g l a c i a t i o n , l a r g e a r e a s o f C re ta c e o u s
b e d ro c k m a n tle d w ith B u ll Lake t i l l s l i d , c r e a t i n g e x t e n s i v e l a n d s l i d e s
mapped on P l a t e I .
B eeh iv e B a s in was a n a r e a o f i c e a c c u m u la tio n seco n d o n ly t o B ear
B a s in i n th e s tu d y a r e a .
The to p o g r a p h ic map o r a r e a l p h o to g ra p h o f
U -sh ap ed B ee h iv e B a s in r e v e a l s i t a s a m a jo r ic e s o u r c e , a lth o u g h i t
f a c e s d i r e c t l y s o u th .
B eeh iv e P e a k , 1 0 ,7 4 2 f e e t e l e v a t i o n , b o r d e r s
th e n o r th o r u p p e r en d o f th e b a s i n .
The u p p e r b a s in f l o o r , a t 9,400
f e e t , g ra d e s i n a s o u t h e r l y d i r e c t i o n f o r t h r e e m ile s t o an e l e v a t i o n
o f 7,800 f e e t , w here th e canyon n a rro w s t o s te e p h ig h w a l l s .
One m ile
below t h i s p o i n t , a t 7 ,2 0 0 f e e t . B eeh iv e C reek d is c h a r g e s i n t o th e
M iddle F o rk .
B eeh iv e B a s in h a s w e ll d e f in e d f l a t f l o o r a r e a s s e p a r a t e d
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Landslide,
Lookout Tower
F ig u re 1 0 a. G l a c i a l and s u r f i c i a l f e a t u r e s in v i c i n i t y o f B eehive
B a s in .
B eeh iv e B a sin
H anging v a l l e y
F ig u re 1 0 b . A r e a l v iew showing th e c ir q u e s o f B eehive
B a sin and th e h a n g in g v a l l e y d r a in i n g i n t o N orth F o rk .
-3 7 b y segm en ts o f s t e e p e r s lo p e .
T h is i s l i k e l y due t o d i f f e r e n t i a l
r o c k r e s i s t a n c e , a s th e P a le o z o ic and M esozoic s e d im e n ts a r e i n c l i n e d
s te e p ly h e r e .
Im m e d ia te ly b elo w th e j u n c t i o n o f B eeh iv e C reek w ith M iddle F o rk
i s a l a r g e ro u n d e d p lu g o f t i l l composed o f c r y s t a l l i n e ro ck s-.
T h is
t i l l c a n b e t r a c e d u p t o a- w e ll d e f in e d k n i f e edged l a t e r a l m o rain e
ab o v e th e lo w e r B eeh iv e C reek canyon (S 2 0 , T6S, R 3E ).
The m o rain e i s
p i c t u r e d on F ig u r e 1 2 . ' The ro u n d e d fo rm and p o s i t i o n o f th e t i l l p lu g
s u g g e s t t h a t i t i s o f B u ll Lake a g e .
I t l i e s a p p ro x im a te ly 5 m ile s
fro m th e s o u r c e a re a ,- an d th u s com pares f a v o r a b l y i n le n g th w ith th e
N o rth F o rk B u ll Lake g l a c i e r w hich h a d a l a r g e r and more e a s t e r l y
s o u rc e c i r q u e an d a s u p p le m e n ta ry i c e s u p p ly from th e h a n g in g v a l l e y .
T h e re i s no e v id e n c e t h a t W isco n sin i c e e x te n d e d f u r t h e r down M iddle
F o rk th a n th e B u ll Lake t i l l p lu g .
The e l e v a t i o n o f th e k n i f e edge l a t e r a l m o ra in e i n d i c a t e s t h a t th e
i c e was a t l e a s t 300 f e e t t h i c k .
The p o s i t i o n o f th e l a t e r a l i n d i c a t e s
t h a t i c e d id n o t s p i l l o v e r th e r i d g e t o th e w est from t h i s lo w er p o s i ­
ti o n .,
The u p p e r l i m i t o f g l a c i a t i o n on th e e a s t s i d e o f th e canyon i s
w e ll d e f in e d an d mapped on P l a t e I .
'
*
To th e w e st o f B ee h iv e C re e k , b etw een U le ry s la k e s an d M o o n lig h t
C re e k , i s a l a r g e t i l l m a n tle d l a n d s l i d e .
The s l i d e a r e a e x te n d s fro m
th e B e e h iv e C reek r i d g e ( M a d is o n - G a lla tin d iv id e ) w e st t o th e ju n c tio n
o f M o o n lig h t C reek an d Lone C re e k , w hich fo rm J a c k C reek .
The s l i d e
■
-3 8 i s up t o 1 .5 m ile s i n w id th fro m U le r y s L akes t o M o o n lig h t C reek , and
i s mapped i n two p a r t s w hich a r e s e p a r a t e d by t i l l m a n tle d b e d ro c k .
Flow l i n e s i n t o M o o n lig h t C reek fro m B eeh iv e B a s in and la c k o f a
l a t e r a l m o ra in e on th e u p p e r B ee h iv e C reek r i d g e ( a t th e h e a d o f th e
s l i d e ) i n d i c a t e t h a t B u ll Lake i c e fro m B eeh iv e C reek s p i l l e d o v er and
m a n tle d th e h i l l s i d e w ith t i l l .
D uring th e P in e d a le d e g l a c i a t i o n , i n ­
c r e a s e d f l u v i a l a c t i v i t y s a t u r a t e d th e C re ta c e o u s b e d ro c k w ith w a te r .
W ith th e a d d i t i o n a l t i l l m a n tle , th e h i l l s i d e r e a c h e d a new e q u i l i ­
b riu m by s lo w ly s l i d i n g and s lu m p in g .
The s l i d e p ro b a b ly w a s n 't
c a ta s tr o p h ic in n a tu re ;
p e rh a p s i t to o k th o u san d 's o f y e a r s f o r t o t a l
movement t o pake p l a c e .
Some s c a r p s a r e s t i l l q u i t e f r e s h and i n d i ­
c a t e p o s s i b l e movement a t th e p r e s e n t tim e .
Movements o f s i m i l a r
s l i d e s , b u t n o t t i l l m a n tle d , h av e b een r e c o r d e d by Kehew (1971) and
W alsh (19 7 1 ) s o u th an d e a s t o f t h i s l o c a t i o n .
The w r i t e r e n v i s i o n s p o s s i b l e downsI ope movement o f 500 to 1,000
fe e t.
T h ere a r e up t o 5 c o n c e n tr ic h eadw ard s c a r p s ,
s h a llo w g r a d i e n t a t th e
lo w er e n d .
b u t a v e ry
Minimum movement may be on th e
o r d e r o f 50 t o 100 f e e t .
F o llo w in g a r e some f e a t u r e s o f th e s e l a n d s l i d e a r e a s :
-3 9 1.
C o n c e n tr ic s c a r p s on th e h i l l s i d e above U le r y s L ak es.
__ _ .JBEEHIVE CREEK
TILL COMESED S H M t
-TILL CCftJEMDSHALC
EXPOSED IN SDHE
SCARPS
2.
a
P e rc h e d swamps and p o n d s.
TILL
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FIGURE H e
4.
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cretaceous
#
t
C re ta c e o u s b e d ro c k slu m p b lo ck s u n d e rn e a th th e t i l l r i d g e
t h a t a p p e a r s to dam th e e a s te r n m o s t U le r y s L ake. The
b e d ro c k i s c o v e re d by 75 f e e t o f t i l l , and i s o n ly ex ­
p o s e d in th e o u t l e t g o rg e .
X
F ig u r e 1 2 . View from A n d e s ite P o in t n o r th t o B eeh iv e
B a s in . N ote s h a rp B u ll Lake l a t e r a l g l a c i a l m o rain e
on th e w e st s id e o f B eeh iv e C re e k . T h is m o rain e l i e s
below th e a r e a o f s l i d i n g .
F ig u re 12. View from A n d e s ite P o in t n o r th t o B eeh iv e
B a s in . Note s h a rp B u ll Lake l a t e r a l g l a c i a l m o rain e
on th e w est s id e o f B eeh iv e C re e k . T h is m o rain e l i e s
below th e a r e a o f s l i d i n g .
>
F ig u re 13.
L a n d s lid e s c a r p in B u ll Lake t i l l w hich form s
c r e s t o f B eeh iv e C reek - M o o n lig h t C reek r i d g e .
-4 3 BEEHIVE PIHEDALE GLACIATIONS
The lo w e r p a r t o f B eeh iv e B a s in i s an a l l u v i a l meadow i n '3 17,
T6S, R3E,
The meadow i s p i c t u r e d i n F ig u r e 14.
I t i s o b v io u s ly th e
r e s u l t o f a dam o f some s o r t , and a l s o m arks th e p o in t w here B eeh iv e
B a s in n a rro w s i n t o a can y o n .
W ith e x c e p tio n o f some s m a ll m udflow s,
t h e m a t e r i a l o f th e m ain damming mass i s g l a c i a l t i l l , ro u g h , b o u ld e ry
and f r e s h lo o k in g .
As i n th e N o rth F o rk , th e v a l l e y w a ll s show s ig n s
o f d e s c e n d in g l a t e r a l - t e r m i n a l m o ra in e s .
In th i s h e a v ily fo r e s te d
r e g i o n , i t i s d i f f i c u l t t o d i s t i n g u i s h b etw een g l a c i a l m o rain e and
t i l l m a n tle d l a n d s l i d e .
The w r i t e r d o es c o n c lu d e , on th e b a s i s o f
f r e s h m o ra in a l f o r m s , e x t e n s i v e f r e s h lo o k in g t i l l d e p o s i t s , d is ta n c e
fro m th e s o u rc e (3 m i l e s ) , and la c k o f a P in e d a le te r m in a l p o s i t i o n
f u r t h e r do w n stream , t h a t t h i s dam m arks t h e maximum e x t e n t o f P in e d a le
g l a c i a t i o n i n B ee h iv e C re e k ,
T h u s, th e P in e d a le o f B eeh iv e C reek was a medium s i z e d v a l l e y
g l a c i e r w ith a le n g th o f t h r e e m i le s .
I n S7, T6S, R3E, i t c o u ld h av e
b een t h i c k enough t o s p i l l o v e r th e canyon w a lls t o th e w e s t, b u t i n
a n i n s i g n i f i c a n t am ount.
I t n e v e r a c h ie v e d th e s i z e n e c e s s a r y t o s p i l l
o v e r an d c o v e r th e e n t i r e U le r y s L akes h i l l s i d e , f o r i t s te r m in a l p o s i ­
t i o n fo rm s a r i g h t a n g le w ith th e L akes an d th e d i r e c t i o n o f f lo w , a s
shown i n F ig u r e 15.
No d i s t i n c t s e c o n d and t h i r d s ta d e P in e d a le te r m in i w ere fo u n d .
I t i s q u i t e p o s s i b l e t h a t th e te r m in i ,of th e f i r s t and seco n d s t a d e s
F ig u re 14.
A l l u v i a l f i l l b e h in d B eeh iv e C reek P in e d a le
te r m in a l p o s i t i o n , lo o k in g n o r th to u p p er B eeh iv e B a s in .
- 4
5
—
N
B E E H N t GLACIER
TERt-VWUS
*
>f
S
ULERYS
LAKES
^
F lB U R t 15
a r e i n d i s t i n g u i s h a b l e from ea c h o t h e r .
BEEHIVE NEOGLACIAL FEATURES
The u p p e r c i r q u e i n B eeh iv e b a s in h a s a f r e s h a p p e a r in g b o u ld e ry
g ro u n d m o ra in e ; b u t a s m e n tio n e d , t h e r e i s no a p p a r e n t t h i r d s ta d e
P in e d a le te r m in a l p o s i t i o n .
T h ere a r e a b u n d a n t N e o g la c ia l f e a t u r e s on
th e e a s t f a c i n g s i d e o f th e s o u th f a c i n g c i r q u e .
T hese s m a ll m o r a in a l
fo rm s a r e n e a r l y i d e n t i c a l t o th o s e fo u n d i n th e h a n g in g v a l l r y w hich
d r a i n s i n t o th e N o rth F o rk .
They a r e e i t h e r sm a ll m o ra in e s o r p ro ­
t a l u s r a m p a r ts .
MOONLIGHT CREEK PIKEDALE GLACIATION
Two s m a ll v a l l e y s o f M o o n lig h t C reek ( S I , 6 , T6S, R 2E), w hich d r a in
s o u th w e s t from B eeh iv e P e a k , c o n ta in s m a ll a r c u a te te r m in a l m o ra in e s .
—46—
The g l a c i e r s w ere up t o 1 /2 m ile i n le n g th and th e m o ra in e s a r e a b o u t
50 f e e t h ig h .
f e e t a p a rt.
Two a d v a n c e s a r e i n d i c a t e d by two m o ra in e s a b o u t 500
They a r e c o n s id e r e d t o be f i r s t and seco n d s ta d e s o f th e
P in e d a le b e c a u s e o f t h e i r f r e s h fo rm and h ig h p o s i t i o n i n a s o u th
f a c i n g v a l l e y ( n o t f a v o r a b l e f o r i c e a c c u m u la tio n ) .
T h ere i s no e v i ­
dence f o r a t h i r d s ta d e P in e d a le g l a c i e r in th e v a l l e y s .
I f th e s e
m o ra in e s r e p r e s e n t th e P in e d a le , th e B u ll Lake m ust h av e b een e x te n ­
s iv e enough t o e x te n d i n t o lo w er M o o n lig h t C reek .
E v id en ce f o r t h i s
i s fo u n d a s t i l l and a p o s s i b l e l a t e r a l m o rain e i n lo w er M o o n lig h t
C re e k .
The a r e a i s a d j a c e n t t o th e l a r g e t i l l m a n tle d l a n d s l i d e from
th e B eeh iv e C reek r i d g e , an d i t a l s o a p p e a rs t o be a t i l l - m a n t l e d
la n d s lid e .
LONE MOUNTAIN WISCONSIN GLACIATION
W isc o n sin g l a c i e r s flo w e d fro m t h e l a r g e c i r q u e on Lone M o u n tain .
The c ir q u e i s p r e s e n t l y o c c u p ie d by r o c k g l a c i e r s .
G l a c i a t i o n h a s s c u lp t u r e d th e p ro m in e n t e a s t f a c i n g c i r q u e o f
Lone M o u n tain .
A lth o u g h a r e a l p h o to g ra p h s r e v e a l t h a t g l a c i e r s flo w ed
from Lone M o u n tain i n s e v e r a l d i r e c t i o n s , th e l a r g e n o r t h e a s t f a c in g
c i r q u e was th e m ain i c e s o u r c e .
1 0 ,0 0 0 f e e t .
The u p p e r c ir q u e l i e s a t 9 ,8 0 0 t o
From t h i s e l e v a t i o n , th e c ir q u e d ro p s t o 8 ,6 0 0 f e e t
b e f o r e le a v in g th e c o n f in e s o f th e m o u n ta in .
A t an e l e v a t i o n o f l e s s th a n 7,5 0 0 f e e t , below th e ' j u n c t i o n of
-4 7 s e v e r a l s m a ll s tre a m s w hich j o i n to form M id d le F o rk , g l a c i a l t i l l o f
a n d e s i t i c c o m p o s itio n (fro m Lone M ountain) a b u t t s c r y s t a l l i n e t i l l
from B ee h iv e B a s in .
B u ll Lake t i l l .
The B eeh iv e B a sin t i l l h a s been c l a s s i f i e d a s
The a n d e s i t i c t i l l fo rm s some ro u n d e d m o ra in a l
r i d g e s , b u t i n g e n e r a l i s r a t h e r f o r m le s s an d subdued.
On th e b a s i s
o f p o s i t i o n and fo rm , t h i s t i l l m arks th e e x t e n t o f B u ll Lake ic e
from Lone M o u n tain .
The g l a c i e r was 3 1 /2 m ile s i n l e n g t h .
Its
s i n g l e c i r q u e s o u rc e was n o t a s g r e a t a s th e s o u rc e s o f th e N orth
F o rk and B eeh iv e C reek g l a c i e r s .
A t 7,6 0 0 f e e t e l e v a t i o n , ab o v e th e B u ll Lake a n d e s i t i c t i l l , i s
a 60 t o 100 f o o t s c a r p , w hich a p p e a r s t o b e a m o ra in a l f r o n t .
The
s c a r p d o es n o t hav e th e t y p i c a l b a c k s lo p e o f a v a l l e y g l a c i e r m o ra in e .
The t i l l m a t e r i a l i s a n d e s i t e and th e r o c k s a r e m o s tly a n g u la r w ith 2
t o 10 in c h d ia m e te r s .
The mass i s v e r y f r e s h and hummocky w ith mor­
a i n a l to p o g ra p h y o f P in e d a le a p p e a r a n c e .
B ecause o f th e la c k o f b a c k -
s lo p e and th e a n g u la r r o c k s , t h i s may hav e been a ro c k g l a c i e r i n s t e a d
of a tru e ic e g la c ie r .
L odgepole P in e .
The a r e a i s c o v e re d w ith a t h i c k f o r e s t o f
On th e b a s i s o f p o s i t i o n an d f o r m ,, t h i s m o ra in a l m ass
o f a n d e s i t i c r u b b le i s a s s ig n e d a P in e d a le a g e .
A lth o u g h a co m p ariso n
o f s o i l d ev elo p m en t on th e B u ll Lake and P in e d a le t i l l s was a tte m p te d ,
th e r e s u l t s w ere to o in c o n c lu s iv e t o b e o f i n t e r p r e t i v e v a l u e .
W hether g l a c i e r o r ro c k g l a c i e r , t h i s f e a t u r e i s d i r e c t l y r e l a t e d t o
i c e a c c u m u la tio n and movement d u r in g th e P in e d a le g l a c i a t i o n .
-4 8 D r i l l i n g a t th e f o o t o f th e P in e d a le s c a r p i n d i c a t e d t h a t th e
outw ash and B u ll Lake m o rain e a r e a b o u t 60 f e e t t h i c k , w ith T h erm o p o lis
S h a le belo w .
A s p r in g a t t h i s l o c a t i o n (S 3 0 , T6S, R3E) h ad s u r f a c e
w a te r a t 3 C, and w e ll w a te r fro m a 60 f o o t d ep th a t 6 C (Van Dyken
D r i l l i n g C o ., P e r s o n a l co m m u n icatio n . S e p t . , 1 9 7 0 ).
INACTIVE ROCK GLACIER
The Lone M ountain r o c k g l a c i e r s a r e diag ram ed and p i c t u r e d in
F ig u r e s 16, 1 7 , and 18,
The P in e d a le g l a c i a l d e p o s it s le a d upw ard i n t o th e m outh o f th e
c i r q u e w here th e y a r e c o v e re d by a N e o g la c ia l ro c k g l a c i e r .
g la c ie r f i l l s
The r o c k
th e c ir q u e f l o o r and i s I m ile lo n g , d ro p p in g fro m
9 ,9 0 0 f e e t to 8,4 0 0 f e e t .
- '
The ro c k g l a c i e r i s o f th e to n g u e sh ap ed
ty p e d e s c r ib e d by W a h rh a ftig and Cox (1 9 5 9 ) , and flo w e d down v a l l e y i n
a to n g u e sh ap ed fo rm .
The r o c k g l a c i e r (lo w e r p a r t e s p e c i a l l y ) h a s
th e t r a n s v e r s e r i d g e s and fu rro w s o b s e rv e d by W a h rh a ftig and Cox on
A la s k a n ro c k g l a c i e r s .
They a r e bowed dow nstream and i n d i c a t e a slo w ­
in g o f v e l o c i t y w hich may be due t o th e u p p e r l a y e r b e in g more r e s i s ­
t a n t t o flo w d e fo rm a tio n an d o v e r t h r u s t i n g from w ith i n ( W ahrhaft i g
and C o x ).
The c h a r a c t e r i s t i c s o f g e n t l e ro u n d ed f r o n t a l s lo p e , l i c h e n -
ed s u r f a c e b o u ld e r s and l i t t l e
e v id e n c e o f f r e s h d is tu r b a n c e on th e
s u r f a c e o r f r o n t , s u g g e s t t h a t t h i s ro c k g l a c i e r i s i n a c t i v e .
The ro c k -
g l a c i e r ’ s s u r f a c e i s composed o f a n g u la r fra g m e n ts o f a n d e s i t e and
-4 9 s e d im e n ta ry r o c k fro m th e c ir q u e h e a d w a ll.
T h is m a ssiv e body o f ro c k
a p p e a r s , f o r th e m ost p a r t , t o be in e q u ilib r iu m w ith th e s lo p e .
F r o n t a l s c a r p s a t v a r i o u s p o s i t i o n s midway up th e ro c k g l a c i e r l i e a t
s te e p a n g le s and a r e u n s t a b l e f o r w alk in g ( a b o u t 100 f e e t h i g h ) .
A l t e r a t i o n by c o n s t r u c t i o n c o u ld p o se p ro b lem s o f i n s t a b i l i t y ,
ACTIVE ROCK GLACIER
I n th e h i g h e s t f l o o r o f th e c ir q u e i s a n o th e r r o c k g l a c i e r .
It
i s a s m a ll (75 f e e t t h i c k a t i t s f r o n t and 1 /4 m ile lo n g ) ro c k g l a c i e r
w ith i t s s o u rc e on th e c ir q u e h e a d w a ll.
I t d i s t i n c t i v e l y l i e s on to p
o f and above th e i n a c t i v e r o c k g l a c i e r j u s t d e s c r ib e d .
I t h a s no
l i c h e n c o v e r , e x h i b i t s f r e s h flo w l i n e s ( l o n g i t u d i n a l fu rro w s ) and h a s
a f r o n t a l e s c a rp m e n t w hich showed some w e tn e ss i n S ep te m b er, 1970.
The w e tn e s s i n d i c a t e s ■t h a t i t s c o re may be i c e o r t h a t a t l e a s t w a te r
p la y s an a c t i v e r o l e i n i t s movem ent.
W hite (1 9 7 1 ), d e s c r ib i n g ro c k
g l a c i e r s i n th e C o lo ra d o F r o n t R ange, s a y s , "W ater t h a t r e a c h e s th e
f r o n t em erges a b o u t 2 /3 o f th e h e i g h t ab o v e th e b a s e ,"
l o c a t i o n o f th e w et zone exam ined on t h i s r o c k g l a c i e r .
i n d i c a t e t h a t i t i s moving o r h a s moved r e c e n t l y .
T h is was th e
The flo w l i n e s
I n v e s t i g a t i o n o f th e
snow f i e l d above th e r o c k g l a c i e r f a i l e d t o d e te rm in e w h e th e r th e
t a l u s r o c k s w ere a c t u a l l y c o v e rin g th e s n o w fie ld f o r p r o d u c tio n o f ic e
by snow p r e s e r v a t i o n u n d e r th e t a l u s . • O th er f e a t u r e s u s e d by
W a h rh a ftig and Cox t o i n d i c a t e r o c k g l a c i e r a c t i v i t y a r e a b a r e s te e p
GLACIAL FEATURLS:LO E MOUNTAIN CIRQUE TO MIDDLE.
FORK
ELEVATION
IN FEET
1 0 , 0 0 0 .;
GANNtTTPLAKRbUGlAUM
TLMPlE LAKE. ROCK GlAOLR
1,000 ..
PlNCDAlL T ill
Bmi LAKE CWWASH UILL—
MIDDLE FOR K —
DISTANCE APPROKIMATELT 3 0 5 MILES
GANNETT PEAK ROCK G lA tlE R FRESH FlflVJ LINES,SHARPlSTttPriOISTFRONXNDlItHEN COVER
TEMPLE LAKE ROCK GLAEIER:
LARGER SUBDUED FRONT LICHtNED SURFACE, SOME TREES
ESTABLISHED
P lN E DALE TILL (GLACIER" ROCK G lA C ltR l
MORAINAL TOPOGRAPHY,FORESTED, SHARP FRONT, NO BACKSLOPE
Bull lake m i w a s h ? T a
FORESTED,SUBbUED FORM
FIGURE IG
F ig u re 1 7 . U pper p a r t o f a c t i v e ro c k g l a c i e r on Lone
M o u n tain , Note f r e s h a n g u la r s i d e s and s u r f a c e flo w
f e a t u r e s . P i c t u r e ta k e n A ugust 7 , 1970.
F ig u re 18.
Lone M ountain c ir q u e a c t i v e and i n a c t i v e ro c k
g l a c i e r s . N ote sh a rp f r o n t o f p a r t l v snow co v ere d a c t i v e
ro c k g l a c i e r . Snow a v a la n c h e s ru n to th e b e g in n in g o f
th e d e n se f o r e s t c o v e r .
-5 3 a n g le d f r o n t , s h a rp a n g le betw een f r o n t and to p an d e x p o su re o f f i n e
g r a in e d l a y e r s i n th e f r o n t a l s c a r p .
W ith i n a c t i v i t y , th e s e f e a t u r e s
a r e soon m o d if ie d , a s w ith th e i n a c t i v e ro c k g l a c i e r .
T h is a c t i v e
ro c k g l a c i e r may be m oving a t a r a t e o f s e v e r a l c e n t im e te r s a y e a r .
W hite (19 7 1 ) g iv e s th e m easu red movement o f t h r e e r o c k g l a c i e r s in
th e C o lo ra d o F r o n t Range a s 5 .0 , 6 . 6 , an d 9 .6 c e n t im e te r s p e r y e a r .
W a h rh a ftig and Cbx (1959) b e l i e v e t h a t m ost r o c k g l a c i e r s a r e
m a n tle d w ith c o a r s e r o c k f r a g m e n ts , th e c o re b e in g o f f i n e r t i l l - l i k e
m a t e r i a l and i n t e r s t i t i a l i c e .
The i c e re s p o n d s t o th e o v e r ly in g
w e ig h t w ith v is c o u s f lo w ( v i s c o s i t y o f 10"^^ t o IO- ^
th e r a t e o f s t r a i n i s p r o p o r t i o n a l t o s t r e s s ) .
p o is e s i n w hich
The i c e s o u rc e c o u ld
b e g ro u n d w a te r , snow m elt p e r c o l a t i o n o r t a l u s c o v e rin g snow and
r e s e r v i n g i t lo n g enough t o become i c e .
The w r i t e r b e l i e v e s t h a t th e l a r g e r i n a c t i v e r o c k g l a c i e r i s of
th e Temple Lake s ta d e o f N e o g la c ia tio n , and t h a t th e s m a lle r a c t i v e
ro c k g l a c i e r i s o f th e G a n n e tt Peak s ta d e o f N e o g la c ia tio n .
T h is
c o r r e l a t i o n i s b a s e d on t h e i r p o s i t i o n above th e W isco n sin g l a c i a l
d e p o s i t s an d la c k o f s u r f a c e v e g e t a t i o n o th e r th a n l i c h e n and s e v e r a l
tre e s .
I n Lone C re e k , w hich d r a in s th e n o r t h s id e o f Lone M o u n tain , th e
w r i t e r h a s mapped i n a c t i v e ro c k g l a c i e r s w hich a r e s m a lle r th a n th e
one p r e v io u s l y d e s c r ib e d .
No f e a t u r e s f r e s h e r th a n Temple Lake w ere
n o te d , w ith e x c e p tio n o f t a l u s and snow a v a la n c h e a c t i v i t y .
-5 4 C o n s tr u c tio n o f r o a d s an d s t r u c t u r e s on th e ro c k g l a c i e r s may be
i n a d v i s a b l e b e c a u se o f t h e i r i n s t a b i l i t y and p o s s i b l e dow nslope
m ovem ent.
ADDITIONAL MASS MOVEMENT FEATURES
R e c e n t S lid i n g
The s tu d y a r e a i s a p p ro a c h in g th e m a tu re s ta g e o f geom orphic
d e v e lo p m e n t.
W ith e x c e p tio n o f f l a t g l a c i a l c i r q u e s , v a l l e y f l o o r s
and n a t u r a l dam a r e a s , m ost o f th e a r e a i s i n s lo p e and th e s tre a m s
a r e a c t i v e l y d o w n c u ttin g .
I n many c a s e s th e h i l l s l o p e s o f C re ta c e o u s
s e d im e n ts and a n d e s i t i c i n t r u s i v e s h av e n o t y e t r e a c h e d e q u i lib r i u m .
T h is h a s r e s u l t e d i n a d ju s tm e n t by mass movement„
The l a r g e t i l l m a n tle d s l i d e s h av e b een ,p r e v io u s ly d e s c r ib e d .
S e v e r a l o t h e r mass movement f e a t u r e s a r e w o rth n o ti n g .
A re c e n t
lo g g in g r o a d on th e n o r t h s id e o f th e M id d le F o rk c an y o n , (SW1/4 S21,
T6S, R 3E), was c u t on a s te e p (25 t o 30 d e g re e s ) s lo p e o f C re ta c e o u s
s a n d s to n e in tr u d e d ' by a s i l l .
The s lo p e i s a t l e a s t p a r t i a l l y w e a th e r­
ed s i l l m a t e r i a l w hich l i e s b e n e a th a n o rth w a rd s t r i k i n g r i d g e of
C re ta c e o u s Muddy S a n d s to n e .
T h is s i l l shows s p h e r io d a l w e a th e rin g and
may be a c o n t i n u a t i o n o f th e m a fic s i l l m e n tio n ed by Kehew (1971) i n
th e a r e a im m e d ia te ly t o th e s o u th a c r o s s M iddle F o rk .
The lo g g in g r o a d
c u t h a s i n i t i a t e d s l i d i n g and th e o p en in g o f some t e n s i o n c r a c k s .
Any
c o n s t r u c t i o n on t h i s h i l l s i d e w ould r e q u i r e e x t r a work and ex p en se f o r
-5 5 s ta b iliz a tio n .
I n S e c tio n s 19 and 2 0 , T6S, R3E, n o r th o f th e p ro p o s e d u p p e r ( s k i )
v i l l a g e s i t e , a r e s e v e r a l t e n s i o n c r a c k s p resu m ab ly r e l a t e d t o la n d s lid in g .
The c r a c k s o c c u r b elow an a r e a mapped a s l a n d s l i d e and i n th e
v i c i n i t y o f s e v e r a l s p r in g s w hich ru n i n t o M iddle F o rk n e a r th e u p p e r
v illa g e s ite .
The c r a c k s , up t o 2 in c h e s i n w id th , a p p e a r f r e s h and
i n d i c a t e i n s t a b i l i t y i n t h i s a r e a , w hich l i e s above th e u p p e r v i l l a g e
s ite .
The u n s t a b l e a r e a i s u n d e r l a i n by T h erm o p o lis S h a le w hich i s on
th e e a s t f l a n k on a n o r t h e a s t p lu n g in g a n t i c l i n e .
m ild ly a c t i v e , ev en i f l e f t u n d is tu r b e d .
T h is a r e a may be
The w r i t e r a d v i s e s t h a t no
c o n s t r u c t i o n ta k e p la c e i n t h i s w et u n s t a b l e a r e a and f e e l s t h a t th e s e
f e a t u r e s s h o u ld be mapped an d m o n ito re d t o d e te rm in e th e p o s s i b i l i t y
o f c a t a s t r o p h i c movement.
1970 L a n d s lid e
A s m a ll s l i d e i s l o c a t e d i n th e NWl1/ 4 S28, T6S, R3E, a d j a c e n t to
t h e lo g g in g a c c e s s r o a d t o th e u p p e r (s„ki) v i l l a g e s i t e .
Muddy s l i d e
d e b r i s c o v e re d th e f o r e s t f l o o r w ith d e v a s t a t i o n on a s m a ll s c a l e .
The s l i d e i s a p p r o x im a te ly 250 f e e t lo n g and 15 f e e t w id e .
I t s ta rte d
i n a bank o f c o l l u v i a l t u f f , c r y s t a l l i n e t i l l , and C re ta c e o u s s h a le
and s a n d s to n e .
I t c r e a t e d i t s own c h a n n e l and flo w le v e e s l i k e an
e a r t h flo w o r mud f lo w i n S h a r p e 's l a n d s l i d e c l a s s i f i c a t i o n (S h a rp e ,
1 9 3 8 ).
T h is s l i d e o c c u r r e d d u r in g th e r a t h e r w et s p r in g o r e a r l y
I
—56—
summer o f 1970,
A lth o u g h o f s m a ll s c a l e , th e v e r y e x i s t e n c e o f t h i s
s l i d e i n d i c a t e s th e g e n e r a l i n s t a b i l i t y o f th e a r e a d u r in g p e r io d s o f
maximum w e tn e s s o r when d i s t u r b e d by c o n s t r u c t i o n .
I t s tro n g ly
s u g g e s ts t h a t s tu d y an d c a u t io n s h o u ld p re c e d e an y c o n s t r u c t i o n a c t i v ­
i t i e s i n th e a r e a .
CAUSES OF SLIDING
Some o f th e p o s t u l a t e d c a u s e s o f th e s l i d e f e a t u r e s a l r e a d y n o te d
a r e t r a d i t i o n a l and w e ll docum ented.
t o th e a r e a .
O th er f a c t o r s seem t o be u n iq u e
The i n i t i a l s i t u a t i o n f o r s l i d i n g in c lu d e s th e a l t e r ­
n a t in g s a n d s to n e s and s h a le s o f C re ta c e o u s b e d ro c k , g l a c i a l o v e r s te e p ­
e n in g on c a n y o n s , p o s s i b l e d o w n c u ttin g o f th e M id d le F o rk canyon an d f o ld e d s t r u c t u r e w ith s te e p s id e d a n t i c l i n e s and s y n c l i n e s .
f a c t o r s te n d e d t o u p s e t th e e q u i lib r i u m .
Two o th e r
T hese a r e :
1.
A d d iti o n a l s u r f a c e lo a d i n th e fo rm o f B u ll Lake t i l l
2.
A v a i l a b i l i t y o f e x c e s s w a te r d u rin g th e P in e d a le d e g l a c i a t i o n
w hich w ould f u l f i l l th e f o llo w in g r o l e s d e s ig n a te d by V arnes
(1 9 5 8 ) f o r s l i d e i n i t i a t i o n :
a.
change i n i n t e r g r a n u l a r f o r c e due t o e x c e s s p o re w a te r
w hich d e s tr o y s c a p i l l a r y t e n s i o n and l u b r i c a t e s enough
t o a llo w v is c o u s flo w
b.
p o s s i b l e s w e llin g and l o s s o f c o h e s io n by m o n t m o r il lo n it ic
an d b e n t o n i t i c c la y s
I t a p p e a r s t h a t some o f th e l a r g e r s l i d e s a r e d i r e c t l y r e l a t e d t o
t h e i r m a n tle o f B u ll Lake t i l l an d t o e x c e s s w a te r o f t h e P in e d a le
-5 7 d e g la c ia tio n .
The w r i t e r i s unaw are o f l i t e r a t u r e r e p o r t i n g o th e r
su ch t i l l m a n tle d l a n d s l i d e s .
Kehew (1 9 7 1 ), who w orked d i r e c t l y t o th e s o u th and e a s t , a t t r i b ­
u t e s m ost o f th e s l i d i n g i n h i s a r e a t o th e b e h a v io r o f C re ta c e o u s
s a n d s to n e , s i l t s t o n e and s h a l e .
The K o o te n a i F o rm a tio n and Muddy
S a n d sto n e (m o s tly r e s i s t a n t s a n d s to n e s ) a r e san d w ich ed i n w ith th e
T h erm o p o lis S h a le , A lb in o F o rm a tio n (w ith th e s w e llin g c l a y m ontm ori l l o n i t e and b e n t o n ite ) and th e U pper C re ta c e o u s U n d i f f e r e n t i a t e d .
M ost o f th e s l i d i n g n o te d by Kehew o c c u rs i n th e T h erm o p o lis S h a le
and A lb in o F o rm a tio n , w hich a r e a l s o p r e s e n t . i n th e s l i d e . r e g io n s
d is c u s s e d i n t h i s r e p o r t .
Some o f th e f e a t u r e s w hich H a ll (1960b) p o s t u l a t e d t o e x p la in
s l i d e phenomena a s h o r t d i s t a n c e t o th e s o u th in c lu d e th e p re s e n c e o f
C re ta c e o u s b e n t o n i t i c c l a y an d f r e q u e n t o c c u rre n q o f e a rth q u a k e sh o ck .
I n th e n e ig h b o r in g M adison V a lle y a r e f a u l t s c a r p s c u t t i n g W isco n sin
( P in e d a le ) g l a c i a l d e p o s i t s .
.
H ence, l a t e Q u a te rn a ry f a u l t i n g may
h av e p ro id e d th e t r i g g e r m echanism f o r some o f th e s l i d i n g .
M ajor
f a u l t i n g i n 1959 n e a r Hebgen Lake and West Y e llo w sto n e i n d i c a t e t h a t
e a r t h tre m o r s a r e s t i l l h a z a r d s i n th e a r e a .
K e r r , S tro u d an d Drew (1 9 7 1 ), i n a d is c u s s io n o f l a n d s l i d i n g i n
th e P lio c e n e P ic o F o rm a tio n n e a r V e n tu r a , C a l i f o r n i a , m e n tio n e d some
a s p e c t s o f s l i d i n g w hich a p p ly t o t h i s s tu d y .
They s t a t e d t h a t
m o n tm o r illo n ite c l a y i s c o n d u civ e t o s l i d i n g b e c a u se i t i s s t a b l e when
-5 8 d ry and m o b ile when w e t.
They n o te d t h a t m ost h i s t o r i c s l i d i n g i n th e
V e n tu ra a r e a o c c u r r e d d u r in g o r a f t e r p e r io d s o f h eav y r a i n , and
s t a t e d t h a t e x c e s s w a te r i s th e m ost im p o rta n t s i n g l e f a c t o r in s l i d ­
in g .
K e e fe r an d Love (1 9 5 6 ) , i n a d e s c r i p t i o n o f th e G ros V e n tre S lid e
and a s s o c i a t e d s l i d e s a lo n g th e Gros V e n tre R iv e r i n n o r th w e s te r n
Wyoming, a t t r i b u t e much o f th e s l i d i n g to b e n t o n i t i c c l a y s to n e and
s h a le o f C re ta c e o u s a g e .
T h is s i t u a t i o n , c o u p le d w ith h ig h p r e c i p i ­
t a t i o n on s t e e p s l o p e s , h a s p ro d u ced e x te n s iv e l a n d s l i d i n g .
They a l s o
s t a t e t h a t w a te r a v a i l a b l e d u rin g p e r io d s o f g l a c i a l m e ltin g c o n t r i b ­
u t e d t o th e s l i d i n g .
RXKEALL
The r a t h e r -lo o se an d w e a th e re d a n d e s i t e an d s e d im e n ta ry ro c k s o f
Lone M ountain a r e s u b j e c t t o r o c k f a l l on s t e e p e r s lo p e s .
Near th e
Lone M oun tain c ir q u e i s a t r a i n o f l a r g e (3 f o o t d ia m e te r) b o u ld e rs
w hich g o es a c r o s s th e lo w er i n a c t i v e ro c k g l a c i e r t o i t s
c i r q u e w a ll .
s o u rc e on th e
The f r e q u e n c y d f l a r g e ro c k f a l l h e r e i s n o t known, b u t
e v id e n c e i n d i c a t e s t h a t many o f th e l a r g e b o u ld e rs h av e t r a v e l l e d a
g r e a t d i s t a n c e a c r o s s th e ro c k g l a c i e r .
t h i s f e a t u r e i n more d e t a i l .
Kehew (1971) h a s d e s c r ib e d
W ith o u t more o b s e r v a ti o n , th e w r i t e r
w ould c a u t io n a g a i n s t any a c t i v i t y o r c o n s t r u c t i o n n e a r t h i s r o c k f a l l ,
w hich may be u n p r e d i c t a b l e .
I t may be p a r t i c u l a r l y s u s c e p ta b le i n th e
-5 9 in s t a n c e o f e a r th q u a k e shock o r d u rin g s p r in g and f a l l f r e e z e - th a w
p e rio d s .
SNOW AVALANCHES
F ig u r e 19 p i c t u r e s snow a v a la n c h e p a th s on W ilson P eak .
The a v a la n c h e o r s n o w s lid e i s an im p o r ta n t a s p e c t o f any e n v iro n ­
m e n ta l i n v e s t i g a t i o n i n th e h ig h Rocky M o u n tain s.
The s tu d y a r e a i s
known t o r e c e i v e a l a r g e w in te r snow pack, and many o f th e h i l l s l o p e s
a r e a t a n g le s o f 20 t o 60 d e g r e e s .
On th e s e s lo p e s , snow a v a la n c h e s
may o c c u r f r e q u e n t l y ( F o r e s t S e r v ic e , U .S .D .A ,, 1 9 6 8 ),
The w r i t e r
o b s e rv e d l a r g e c lim a x a v a la n c h e s i n m id -J u n e , 1970, i n th e N o rth F o rk
can y o n .
These s l i d e s f l a t t e n e d t r e e s e s tim a te d to be 40 y e a r s old®
E v id e n c e o f s i m i l a r a v a la n c h e s w ere fo u n d i n th e M o o n lig h t C reek a r e a ,
w here up t o two a c r e s o f m a tu re p in e t r e e s w ere f l a t t e n e d by a s i n g l e
a v a la n c h e .
T h u s, an a r e a o f m a tu re f o r e s t a d ja c e n t t o an a v a la n c h e
p a th may be s u b j e c t t o damage i n r a r e c lim a x a v a la n c h e s i t u a t i o n s .
I n s p e c t i o n o f t r e e damage r e v e a l s a b u n d an t a v a la n c h e p a th s i n B ear
and B eeh iv e B a s in s and on Lone M o u n tain .
A v alan ch e p a th s n o te d by th e
w r i t e r a r e mapped on P l a t e I .
The s te e p open c ir q u e w a lls and s lo p e s o f Lone M o u n tain form some
l a r g e a v a la n c h e p a th s w hich w ould r e q u i r e c o n t r o l by q u a l i f i e d p e r ­
s o n n e l i f t h a t a r e a becom es a s k i a r e a .
F o rm atio n o f show c o r n ic e s
on th e lo w e r s o u th e r n c ir q u e w a ll w ould r e q u i r e c o n t r o l by e x p l o s i v e s .
F ig u re 19.
D e n d r iti c a v a la n c h e p a th s on th e f o r e s t e d s lo p e s
o f W ilson P eak , N o rth F ork d r a in a g e .
— 6 1 —
I f p e o p le u s e th e a r e a in th e w in te r , c r o s s - c o u n tr y t r a v e l r e ­
s t r i c t i o n s m ig h t be im posed d u r in g p e r io d s o f a v a la n c h e d an g er on
Lone M o un tain and on a c c e s s r o u t e s t o B eeh iv e and B ear B a s in s .
Ava­
la n c h e d an g er p o s e s no p ro b lem s f o r c u r r e n t a c c e s s r o a d s .
PRE-WISCONSIN WELDED TUFF AND TILL
The w r i t e r d is c o v e r e d two s m a ll o u tc ro p s o f w eld ed t u f f o f p r e ­
sumed Q u a te rn a ry a g e .
I n h an d specim an fo rm , i t a p p e a r s i d e n t i c a l
t o w eld ed t u f f w id e s p re a d i n Y e llo w sto n e N a tio n a l P a rk .
T h is i s th e
n o rth e rn m o s t o c c u rre n c e o f "Y e llo w sto n e T u ff" known t o th e w r i t e r .
The e a s te r n m o s t o f th e two w eld ed t u f f d e p o s it s i s lo c a te d a t
7,500 f e e t i n S 28, T6S, R3E.
M iddle F o rk canyon f l o o r .
T h is p o s i t i o n i s 700 f e e t above th e
I t l i e s o u ts id e th e b o u n d ary o f th e N o rth
F o rk B u ll Lake g l a c i a t i o n , y e t i t i s a s s o c i a t e d w ith a t i l l o f
c r y s t a l l i n e r o c k s w ith a f i n e san d y m a tir x .
I t was n o t p r a c t i c a l to
a s s e s s th e d e g re e o f s o i l dev elo p m en t - i n th e t i l l , n o r t o d e te rm in e
.
w h e th e r t h e w eld ed t u f f l i e s above o r below th e t i l l a t t h i s l o c a t i o n .
On t h e b a s i s o f p o s i t i o n above and beyond th e B u ll Lake g l a c i a l
b o u n d a ry , th e w r i t e r b e l i e v e s t h i s t i l l t o be p re -W is c o n s in i n a g e .
I f th e w eld ed t u f f c o u ld be p ro v e n t o l i e above th e t i l l ,
th e age o f
th e t u f f w ould p r o v id e a minimum ag e f o r th e p a r t i c u l a r p re -W is c o n s in
g la c ia tio n .
The w e ste rn m o st w elded t u f f d e p o s it i s a t 8,000 f e e t e l e v a t i o n
-6 2 i n S20 , T6S RSE, w here i t form s a c l i f f and t a l u s s lo p e above B eehive
C reek .
I t l i e s a t th e h ead o f a t i l l co v ere d l a n d s l i d e i n th e B eehive
canyon.
The w elded t u f f c l e a r l y l i e s b e n e a th a t i l l d e p o s it and i s
above th e mapped B u ll Lake g l a c i a l bo u n d ary i n B eeh iv e C reek .
A g ain ,
p re -W is c o n s in t i l l i s p o s t u l a t e d , b u t th e t i l l i s c l e a r l y younger th a n
th e t u f f .
R. L. C h r i s t i a n s e n , o f th e U. S. G e o lo g ic a l S u rv ey , D e n v e r ,'
C o lo ra d o , ( P e r s o n a l co m m u n icatio n , 1 9 7 1 ), h a s i d e n t i f i e d t h i s w elded
t u f f by p a le o m a g n e tic m ethods a s H u c k le b e rry R idge T u f f , p a r t o f h i s
Y e llo w s to n e G roup.,
y e a rs.
H u c k le b e rry R idge T u ff h a s a K-Ar d a te of 2 m i l l i o n
C h r i s t i a n s e n f u r t h e r i n d i c a t e s t h a t t h i s w elded t u f f f i l l e d a
c o n tin u o u s b ro a d v a l l e y ( t h e a n c e s t r a l G a l l a t i n v a l le y ) b etw een th e
G a l l a t i n and M adison R an g es.
The h ig h l e v e l o f th e s e w elded t u f f d e p o s its above th e M iddle
F o rk and B eeh iv e C reek canyons may i n d i c a t e th e e x t e n t o f stre a m down­
c u t t i n g s in c e w elded t u f f d e p o s it io n (2 m i l l i o n y e a r s in a t l e a s t one
c a se ),
A l t e r n a t i v e l y , th e d e p o s it s may h av e e x te n d e d low er i n t o th e
s tre a m v a l l e y and th e s e re m n a n ts may occupy to p o g ra p h ic p o s i t i o n s
l e a s t v u ln e r a b le t o e r o s i o n .
K. L. P i e r c e (1970) r e p o r t s d e p o s i t s o f p o s s i b le g l a c i a l o r i g i n
o v e r l a i n by 2 and .6 m i l l i o n y e a r o ld w elded t u f f d e p o s it s in n o r th e r n
Y e llo w sto n e N a tio n a l P a rk .
He f u r t h e r s t a t e s t h a t Sacagawea Ridge t i l l
( t h e l a t e s t o f th e p r e - B u l l Lake g l a c i a t i o n s ) l i e s on th e s e w elded
tu ffs .
Thus th e t i l l s u n d e r d is c u s s io n may p o s s i b ly be c o r r e l a t e d w ith
—63'
th e Sacagaw ea R id g e G l a c i a t i o n o f Richmond .(1 9 6 5 ).
The s m a ll l a n d s l i d e o f 1970 (NW1/4 S28, T6S, R 3E ), d e s c r ib e d on
p a g e s 55 and 5 6 , ex p o se d a t i l l b u r ie d by c o llu v iu m . The t i l l f r a g \
m ents c o n s i s t o f c r y s t a l l i n e r o c k s w ith some w elded t u f f . T h is lo c a ­
t i o n i s a l s o o u ts id e th e mapped l i m i t s o f B u ll Lake g l a c i a t i o n ; in
f a c t , i t l i e s a lm o s t d i r e c t l y below th e e a s te rn m o s t w elded t u f f
d e p o s it.
T h u s, a B u ll Lake g l a c i a t i o n c l e a r l y o c c u rre d a f t e r t u f f
d e p o s itio n .
The w r i t e r b e l i e v e s t h a t th e s e w elded t u f f a s s o c i a t e d t i l l s w i l l
c o r r e l a t e w ith t h e Apex t i l l an d M arb le P o in t s t a g e , w hich o c c u r in
th e M adison Range t o th e s o u th ( H a l l , 1 9 6 0 a ),
The t i l l s mapped by
H a ll a r e a t h ig h e l e v a t i o n s and r a t h e r f a r . from t h e i r s o u rc e s i n th e
h ig h M adison R ange.
i c e cap t y p e .
They i n d i c a t e e x te n s iv e g l a c i a t i o n o f th e l o c a l
The t i l l s
i n th e l a n d s l i d e s c a r p and th e t i l l s a s s o c i ­
a t e d w ith th e w elded t u f f d e p o s it s a r e h ig h above th e B u ll Lake
g la c ia l lim its .
T h is e v id e n c e i n d i c a t e s th e p o s s i b i l i t y o f a l o c a l
i c e cap e m a n a tin g fro m th e S p a n ish P eaks and f i l l i n g th e West F ork
b a s i n w ith i c e .
I t i n d i c a t e s g l a c i a t i o n on a much l a r g e r s c a l e th a n
th e W isco n sin v a l l e y g l a c i e r s .
H a ll (1 9 6 0 a ), h a s e v id e n c e f o r a
s i m i l a r g l a c i a t i o n s o u th o f th e s tu d y a r e a .
Richmond (1 9 7 0 ), s t a t e s
t h a t i n Y e llo w s to n e R a t i o n a l / P a r k , th e Sacagawea R idge g l a c i a t i o n
f i l l e d th e Y e llo w s to n e Lake b a s in w ith a l o c a l ic e cap w hich flo w ed
o v e r th e b a s in rim .
T h u s, t h e r e i s p o s s i b l e e v id e n c e f o r a
—64—
p re -W is c o n s in ic e cap i n th e S p a n is h P eak s w hich f i l l e d much o r a l l
o f th e West F o rk b a s in w ith i c e .
ADDITIONAL ASPECTS OF ENVIRONMENTAL GEOLOGY
AND RECOMMENDATIONS
— 6
6
-
INTRODUCTION
The l a s t s e c t i o n d e s c r ib e d v a r io u s mass movement f e a t u r e s w hich
a r e mapped on P l a t e I .
T h is s e c t i o n d e a ls w ith th e g e o l o g i c a l e n v i­
ronm ent o f t h e p ro p o s e d u p p e r ( s k i ) v i l l a g e c o n s t r u c t i o n a r e a , g e o lo ­
g i c a l im p l i c a t i o n s o f r o a d c o n s t r u c t i o n , e n v iro n m e n ta l i m p lic a tio n s
o f v a r io u s s o i l s an d t h e i r c o r r e l a t i o n w ith th e g eo lo g y and a r e a s w hich
a r e recommended a s n a t u r a l r e s e r v e s .
A map i s p r e s e n te d show ing a r e a s
w hich may be u n s u i t a b l e f o r c o n s t r u c t i o n and s u b s e q u e n t u s e b e c a u se
o f g e o lo g ic f e a t u r e s .
UPPER VILLAGE AREA
The f o llo w in g c o n c e rn s th e a r e a in c lu d in g and s u r r o u n d in g
S e c tio n s 19 an d 3 0 , T6S, R3E.
T h is i s th e a r e a o f B ig S k y ’ s p ro p o sed
upper v illa g e .
B u ll Lake t i l l an d outw ash d e p o s i t s c o n s i s t i n g o f a n d e s i t i c
d e b r is fro m th e Lone M ountain a r e a h av e b een mapped a t th e u p p e r
v illa g e s i t e .
T liis m a t e r i a l i s low i n c la y c o n te n t and w ould n o t be
s u b j e c t t o th e r e s t r i c t i o n s w hich c l a y im poses f o r b u i l d i n g p u rp o s e s
(p o o r d r a in a g e and low p e r m e a b i l i t y ) .
T hus, t h i s a r e a s h o u ld have good
f o u n d a tio n an d ro a d c o n s t r u c t i o n c o n d i t i o n s .
W ater w e ll d r i l l i n g
( P e r s o n a l com m u n icatio n . Van Dyken D r i l l i n g
C o ., 1970) i n th e t i l l an d outw ash d e p o s it s b o u n d ary b etw een NW 1 /4 and
NE 1 / 4 , S3 0 , T6S, R3E) b elo w th e f r o n t o f th e Lone M ountain P in e d a le
-6 7 m o ra in e r e v e a l e d a b o u t 60 f e e t o f a n d e s i t i c t i l l and outw ash d e b r i s .
A t a d e p th o f 70 f e e t , C re ta c e o u s s h a le b ed ro ck was e n c o u n te r e d .
It
i s a l s o ex p o sed a lo n g th e c r e e k d i r e c t l y n o r th o f th e w e ll l o c a t i o n .
The v e n e e r o f t i l l and outw ash m ust g e t th i n n e r n o r th to w ard th e
c re e k .
S h a le i s r e l a t i v e l y im p erm eab le t o w a te r and may e f f e c t i v e l y
b lo c k downward movement o f l i q u i d an d d i r e c t i t h o r i z o n t a l l y to w ard
th e c r e e k .
The meadows (S 1 9 , T6S, R3E) a lo n g th e e a s tw a rd flo w in g t r i b u t a r y
t o M iddle F o rk a l l c o n s i s t o f f i n e g r a in e d a llu v iu m .
C u rso ry exam in­
a t i o n d u r in g th e summer i n d i c a t e s t h a t - t h e y re m a in w et m ost o f th e
tim e .
Some s p r i n g s w ere a l s o n o te d , p r o b a b ly i n d i c a t i n g th e p r o x im ity
t o s h a le b e d ro c k .
Much o f t h i s meadow la n d may h av e c la y e y s o i l w hich
i s u n s t a b l e when w et due t o p o o r d r a in a g e and p o s s i b l e s w e llin g c l a y s .
D u rin g f r e e z e - th a w p e r io d s f r o s t h e a v e i s p r o b a b ly a c t i v e .
C o n s tru c ­
t i o n i n th e meadow a r e a s s h o u ld n o t b e u n d e r ta k e n w ith o u t d e t a i l e d
s o i l i n v e s t i g a t i o n s t o a c o n s id e r a b le d e p th (10 t o 15 f e e t ) .
The .
meadows a r e a l s o im p o r ta n t c o n t r i b u t o r s t o th e n a t u r a l b e a u ty and
e c o lo g y o f th e a r e a .
The h i l l s i d e d i r e c t l y n o r t h o f t h e c r e e k i n S e c tio n 1,9, T6S, RSE,
i s a n a n t i c l i n e in v o lv in g th e C re ta c e o u s K o o ten ai F o rm a tio n a t th e
s u r f a c e (S w anson, 1 9 5 0 ).
The n a t u r a l meadow a r e a s o f t h i s h i l l s i d e
l i e on s h a le y b e d ro c k , w hich fo rm s a s i l t y s o i l m o re " fa v o ra b le to
g r a s s p r o d u c tio n th a n a d j a c e n t san d y s o i l d ev elo p ed on s a n d s to n e
— 6 8 ~
b e d ro c k ,
L o d g ep o le p in e i s b e t t e r a d a p te d t o th e l a t t e r .
The expo­
s u r e o f th e a n t i c l i n e i s a lo n g a s te e p h i l l s i d e , bounded on th e
»V
*
n o r t h e a s t by th e a r e a o f a c t i v e s l i d e cra.ck s p r e v io u s ly d e s c r ib e d .
S u rro u n d in g th e a n t i c l i n e t o th e n o r th a r e a l t e r n a t i n g o u tc ro p s _ o f
s a n d s to n e an d s h a le ( T h erm o p o lis S h a le and Muddy S a n d s to n e ) .
The
b e d ro c k i s c o v e re d t o th e e a s t , n o r th an d w e st by B u ll Lake t i l l from
• B e e h iv e B a s in eThe a c t i v e c r a c k s i n d i c a t e t h a t p a r t s o f th e h i l l s i d e may be
u n s ta b le .
On a s m a l le r s c a l e , th e c la y e y s o i l d ev e lo p e d on th e s h a le
( P i c t u r e d i n F ig u r e 2Ch) w ould o f f e r e n g in e e r s p ro b lem s o f p o o r
d r a in a g e and f r o s t h e a v in g .
The sandy s o i l ( P i c t u r e d i n F ig u re 20b)
d e v e lo p e d on th e a l t e r n a t e s a n d s to n e b e d ro c k h a s good p e r m e a b il ity and
d r a in a g e , b u t s t i l l i s v e r y f r a g i l e f o r ev en l i g h t t r a n s p o r t a t i o n u s e .
No f a c t o r i s more im p o r ta n t t o th e p la n n in g o f open sp a c e th a n
th e in d ig e n o u s s o i l s .
Topography an d g e o lo g y a r e p a r t l y re s p o n ­
s i b l e f o r th e d i s t r i b u t i o n o f s o i l s , and a r e i n th e m s e lv e s f a i r l y
o b v io u s l i m i t i n g f a c t o r s . B ut th e ra g g e d p a th s and b a r e p a tc h e d
law ns o f t e n fo u n d i n p u b li c la n d a r e e v id e n c e t h a t th e d e s ig n e r
was un aw are o f th e s o i l ’ s c a p a c it y t o w ith s ta n d e r o s io n o r
ta m p e rin g , o r t h a t h e h ad p la n n e d f o r a much lo w er l e v e l o f u s e .
Sandy s o i l s a r e p a r t i c u l a r l y s e n s i t i v e t o s u r f a c e d is tu r b a n c e
and e r o d e v e r y e a s i l y , y e t t h e i r good d r a in a g e an d re a d y
s u b m is s io n t o th e b u ll d o z e r o f te n le a d them t o be c o n s id e r e d
i d e a l f o r p la y g ro u n d s and p a r k s . The p ro p e r v e g e t a t i o n and th e
p r o p e r s o i l f o r ea c h ty p e o f u s e s h o u ld be d i l i g e n t l y s o u g h t.
( T unnard and P u sh k a re v , 1963)
The U le ry s L akes a r e a , w hich i s a l a n d s l i d e , may n o t be s u i t a b l e
f o r c o n s tru c tio n .
s h a le b e d ro c k .
The a r e a i s v e ry w e t, i n d i c a t i n g th e p r o x im ity t o
The w r i t e r w ould n o t recommend c o n s t r u c t i o n i n t h i s
F ig u re 2 0 a , C lay s o i l on s h a le b e d ro c k n o r th o f u p p e r
v i l l a g e s i t e (S 1 9 , T6S, R3E).
F ig u re 20 b . Sandy s o i l d ev e lo p e d on s a n d s to n e a d j a c e n t
t o s h a le an d c la y s o i l o f F ig u re 2 0 a , n o r th o f th e
upper v illa g e s i t e .
-7 1 are a .
,
T h u s, th e e n t i r e a r e a i s f r a g i l e .
,Heavy u s e and a l t e r a t i o n may
u p s e t th e e q u i lib r i u m o f th e f o r e s t and g r a s s la n d f l o o r .
A reas o f
g l a c i a l t i l l and outw ash seem to be b e t t e r f o r c o n s t r u c t i o n u s e th a n
a r e a s o f C re ta c e o u s b e d ro c k .
i s unim pro v ed sandy s o i l .
C lay s o i l i s u n s u ite d t o h eav y u s e , a s
The a r e a s h o u ld be managed w ith r e s p e c t f o r
i t s s o i l c o n d i tio n s an d b e d ro c k and s u r f i c i a l g e o lo g y , a l l o f w hich
have c r i t i c a l n e g a tiv e and p o s i t i v e a s p e c t s .
Much o f S e c tio n s 19 and 3 0 , T6S, R3E, have been c l e a r c u t i n r e c e n t
y e a rs.
F ig u r e 21 i s a p h o to g ra p h o f th e c l e a r c u t a r e a .
T h is c u t t i n g
h a s ex p o sed a r e a s o f t i l l and C re ta c e o u s b e d ro c k t o a c c e l e r a t e d
e r o s io n by w a te r .
A lth o u g h no q u a n t i t a t i v e m easurem ents o f s o i l
n u t r i e n t an d d e t r i t a l m a t e r i a l l o s s w ere made, an i n s p e c t i o n o f th e
c r e e k s d r a in i n g t h e a r e a r e v e a l s i t s s u s c e p t i b i l i t y t o e r o s i o n .
C hanges i n th e l e v e l o f a s m a ll c r e e k (N E1/4S30, T6S, R3E) w hich d r a in s
th e c l e a r c u t a r e a w ere m e asu re d .
T h is was com pared w ith a s i m i l a r
c re e k d r a in i n g an a r e a o f f o r e s t e d t i l l .
The f o llo w in g was o b s e rv e d .
D ate:
S eptem ber 8 , 1970
Time p e r io d :
IOAM t o 3 PM
O b s e r v a tio n s : / A f t e r an e s tim a te d 1 .5 in c h e s o f r a i n f a l l , th e
c r e e k l e v e l r o s e a p p ro x im a te ly 10 in c h e s and o v e rflo w e d
i t s b anks in p l a c e s . F ig u r e 22 shows th e c r e e k a t i t s
h ig h w a te r p eak d u rin g th e p e r io d o f m easu rem en t. The
w a te r changed from c l e a r t o v e ry d i r t y brow n.
D u rin g th e same p e r io d , th e sm a ll c re e k flo w in g n o rth w e s t
t o j o i n th e one u n d e r d is c u s s io n and form M iddle F o rk
becam e o n ly s l i g h t l y m ilk y and d id n o t r i s e a p p r e c ia b ly .
F ig u re 21.
View from A n d e s ite to c l e a r c u t a r e a in S e c tio n s
19 and 3 0 , T6S, R3E. A n t i c l i n e d ev elo p ed on C re ta c e o u s
K o o te n a i Fm. v i s i b l e above r o a d . B eehive B a sin in b a c k g ro u n d .
F ig u re 22.
C reek d r a in i n g c l e a r c u t a r e a in S e c tio n s 19 and
30, T6S, R3E, a f t e r 1 .5 in c h e s o f r a i n f a l l in s i x h o u rs .
W ater l e v e l h as r i s e n a p p ro x im a te ly 10 in c h e s .
-7 4 T h is c r e e k d r a in s th e f o r e s t e d a r e a b etw een A n d e s ite P o in t
and Lone M o u n tain . The s u r f a c e o f th e d r a in a g e i s com­
p o sed p r i m a r i l y o f a n d e s i t i c t i l l , a lth o u g h one b ra n c h o f
th e c r e e k r u n s a lo n g th e s t r i k e o f th e Muddy S a n d sto n e
(Kehew, 1 9 7 1 ). The d r a in a g e i s e n t i r e l y f o r e s t e d .
ROAD BUILDING
The l a n d s l i d e s mapped on P l a t e I a r e o b v io u s h a z a r d s t o n e a r ly
any ty p e o f c o n s t r u c t i o n .
I n many c a s e s , t h e ,e q u i l i b r i u m c o u ld e a s i l y
be d i s t u r b e d by c o n s t r u c t i o n e i t h e r on l a n d s l i d e s o r on l a n d s l i d e
p ro n e s i t e s , a s h a s b e e n docum ented i n t h i s r e p o r t .
L a n d s lid e p ro n e
s i t e s o f t e n o c c u r i n c o n ju n c tio n w ith a l t e r n a t i n g s a n d s to n e s and
s h a l e s , w hich h av e n o t b een mapped i n d e t a i l i n th e w r i t e r ' s s tu d y
are a .
One l a n d s l i d e , a p p a r e n t l y i n i t i a t e d by a lo g g in g r o a d , o c c u rs in
and b e n e a th a s p h e r o i d a l l y w e a th e re d s i l l (p ag e 5 4 - 5 5 ) . T h is p a r t i c $
u I a r ^ i l l may be more v u ln e r a b le t o w e a th e rin g and d i s i n t e g r a t i o n th a n
th e s a n d s to n e u n i t a b o v e .
T hus, s i l l s may be h a z a r d s t o c h e c k f o r
b e f o re c o n s t r u c t i o n . __Some o f th e h ig h l y w e a th e re d s i l l s a r e t h i n and
h a r d t o f i n d ..
SOILS CORRELATIONS
J . A. O lsen and B ru ce L eeson d id a s o i l s u rv e y o f th e G a l l a t i n
Canyon a s p a r t o f th e N a tio n a l S c ie n c e F o u n d a tio n fu n d e d p r o j e c t . The
Im p act o f a L arg e R e c r e a ti o n a l D evelopm ent On A S e m ip rim a tiv e E n v iro n ­
m e n t.
The s o i l s u rv e y c o v e re d a l a r g e a r e a , and i s n o t a d e t a i l e d
-7 5 a s t h e g e o l o g i c a l s tu d y .
H owever , th e w r i t e r w ould l i k e t o p o i n t o u t
some p o s s i b l e c o r r e l a t i o n s b etw een th e two s t u d i e s an d add some de­
t a i l t o th e s o i l s in f o r m a tio n .
The C o r r e l a t i o n C h a rt ( F ig u r e 23) and
th e f o llo w in g p a r a g r a p h s com pare th e s o i l a s mapped t o th e s u r f i c i a l
g e o lo g y a s mapped.
The a r e a mapped a s L oberg and B e rg lo s to n y loam in c lu d e s a l l o f
th e t i l l - c o v e r e d a r e a s b etw een N o rth F o rk and U le ry s L a k e s, in c lu d in g
th e t i l l c o v e re d l a n d s l i d e s and th e u p p e r ( s k i ) v i l l a g e s i t e , w hich
i s lo c a t e d on t i l l an d o u tw ash .
The L oberg i s a T ypic C r y o b o r a lf .
I t o c c u rs on f o r e s t e d a r e a s w ith a to p la y e r o f o r g a n ic d u f f , a g ra y
loam A2 h o r iz o n , an i l l u v i a l B2t h o r iz o n and a C h o r iz o n .
The l o c a t i o n
o f th e r e p r e s e n t a t i v e p r o f i l e , w hich was sam pled by O lsen an d L ees o n ,
i s on B u ll Lake t i l l fro m B eeh iv e B a s in .
n o s t i c o f B u ll Lake t i l l i n th e a r e a .
T h is s o i l p r o f i l e i s d ia g ­
I t h ad i l l u v i a l c l a y t o 72
in c h e s (B 2 t h o r iz o n ) and le a c h in g o f c a lc iu m c a r b o n a te t o th e C
h o r iz o n a t 70 t o 84 in c h e s .
T h is i s s i m i l a r t o th e B u ll Lake s o i l
p r o f i l e s p r e v io u s l y d e s c r ib e d i n t h i s r e p o r t . ■
The to p l a y e r s o f t h i s s o i l d i f f e r from th e B u ll Lake s o i l de­
s c r i b e d i n a g r a s s la n d a r e a ( F ig u r e 6a and 6 b ) .
I n th e f o r e s t e d
s o i l s , th e A h o r iz o n i s one o f le a c h in g o f c l a y , o r g a n ic m a tte r and
o x id e s .
I n th e g r a s s la n d s o i l s , a t h i c k b la c k m o llic e p ip e d o n form s
b e c a u se th e o r g a n ic m a tte r i s n o t le a c h e d downward.
—76F ig u r e 23.
C o r r e l a t i o n o f s o i l s and s u r f i c i a l g e o lo g y .
S o i l s an d l o c a t i o n ________________ G eology___________Common F e a tu r e s
G a r l e t A n g u la r g r a v e l l y loam
com plex.
T y p ic C r y o c h r e p t, mapped i n
C re ta c e o u s b e d ro c k betw een
N o rth F o rk an d B eeh iv e C k .,
a f o r e s t s o i l w ith l i t t l e
i l l u v i a l c la y .
C r e t , B edrock a r e a
d r a in e d by c r e e k i n
F ig . 2 2 , h ig h r u n o f f
an d se d im e n t lo a d
due t o b e d ro c k and
lo g g in g .
No t i l l c o v e r .
R am bler s to n y and v e r y •
c o b b ly loam .
T y p ic C ry o rt h e n t , f o r e s t
s o i l w ith l i t t l e h o r iz o n a t i o n , w e ll d r a in e d , slo w
r u n o f f , mapped i n a r e a of
upper v illa g e s i t e .
D ev elo p ed on P in e d a le a n d e s i t i c t i l l .
C reek h e r e was n o t
a d v e r s e l y in f lu e n c e d
by h e a v y r a i n .
T y p ic a l P in e d a le s o i l w ith
l i t t l e h o r iz o n ­
a tio n .
L e a v i t t S to n y loam .
A rg ic C ryobo r o i l , g r a s s ­
la n d s o i l s on t i l l .
Mapped a s B u ll Lake
t i l l n o r th o f C r a i l
Ranch ( F ig . 6 a , 6 b ) .
T h is s o i l i s
mapped a lm o s t
e n t i r e l y on
B u ll Lake t i l l .
K is s i c k ( c la y )
V e r t i c C ry o b o r o i l , m apped
on t e r r a c e s a lo n g th e
G a lla tin R iv e r,
C la y s o i l on
s h a le b e d ro c k , h eav y
w et c l a y w ith l i t t l e
h o riz o n a tio n , ' ,
F ig u r e 2 0 a.
May be a b le
to c o rre la te
w ith o c c u rre n c e
o f T h erm o p o lls
S h a le .
L oberg an d B e rg lo s to n y
loam
A T ypic C r y o b o r a lf , f o r e s t
s o i l , B 2t t o 7 2 " , Ca
le a c h in g t o 7 0 -8 4 " .
S o i l i s mapped
e n t i r e l y on B u ll
Lake t i l l and t i l l "
m a n tle d l a n d s l i d e s .
The r e p r e s e n t ­
a tiv e p ro file is
d i a g n o s t i c of
B u ll Lake t i l l .
J
-7 7 The B e rg lo S e r i e s i s i d e n t i c a l t o th e L o b e r t, e x c e p t f o r th e
p r e s e n c e o f c a lc iu m c a r b o n a te b etw een 30 an d 60 -in c h e s „
As m e n tio n e d ,
th e mapped b o u n d a r ie s f o r th e L o b e rt and B e rg lo s to n y loam s f o llo w th e
b o u n d a rie s o f th e B u ll Lake g l a c i a l and a s s o c i a t e d l a n d s l i d e d e p o s i t s .
The G a r l e t A n g u la r g r a v e l l y loam com plex i s mapped b etw een N o rth
F o rk and B eeh iv e C reek on a r e a s o f C re ta c e o u s b e d ro c k .
S e r ie s i s a T y p ic C r y o c h r e p t,
and an A2 h o r iz o n .
The G a r le t
I t i s a f o r e s t s o i l w ith a d u f f l a y e r
I t has r e la tiv e ly l i t t l e
B 2t h o r i z o n ) , i n c o n t r a s t t o th e L o b e rg .
c la y a c c u m u la tio n (no
The two s o i l s h av e n e a r ly
i d e n t i c a l s o i l fo rm in g f a c t o r s o f r e l i e f , c lim a te and o rg a n is m s , b u t
d i f f e r e n t f a c t o r s o f p a r e n t m a t e r i a l and tim e .
The t i l l p a r e n t m a te r­
i a l o f th e L oberg may h av e h ad enough f i n e m a t e r i a l i n i t a t th e tim e
o f d e p o s i t i o n t o a i d i n th e f o r m a tio n o f th e i l l u v i a l (B 2 t) c la y
h o r iz o n .
C la y i n th e G a r l e t s o i l s w ould h av e t o b e fo rm ed i n s i t u fro m
b e d ro c k .
The f a c t o r o f tim e may a l s o b e in v o lv e d ; G a r l e t s o i l s d e v e l­
oped on th e s te e p b e d ro c k s lo p e s may hav e b een p a r t i a l l y rem oved by
P in e d a le s o l i f l u c t i o n and f l u v i a l a c t i v i t y , r e q u i r i n g t h a t a new s o i l
be form ed on th e b e d ro c k .
C o n v e rs e ly , th e s o i l on th e B u ll Lake t i l l
may n o t h a v e b een d i s t u r b e d by P in e d a le p r o c e s s e s .
I f i t w as, one
w ould n o t e x p e c t t o f i n d a g r e a t d i f f e r e n c e b etw een B u ll Lake and
P in e d a le s o i l s .
The a r e a w e st o f th e u p p e r v i l l a g e s i t e , g e o l o g i c a l l y mapped a s
P in e d a le t i l l , i s a l s o mapped a s R am bler s to n y and v e r y c o b b ly loam .
- 7
The R am bler i s a T y p ic C r y o th e n t.
h o r iz o n and l i t t l e
8
-
I t i s a f o r e s t s o i l w ith an A2
a d d i t i o n a l h o r iz o n d i f f e r e n t i a t i o n .
y o u n g e r th a n th e Loberg=
The s o i l i s
I t i s d e v e lo p e d on P in e d a le a n d e s i t i c t i l l .
The r e p r e s e n t a t i v e p r o f i l e a p p e a rs s i m i l a r i n d e g re e o f developm ent
t o th e P in e d a le s o i l i n N o rth F o rk ( s e e F ig u r e 8 ) .
B oth s o i l s have
A2 h o r iz o n s t o 15 in c h e s , th e n C h o r iz o n s .
The R am bler i s w e ll d r a in e d , b u t h a s slo w r u n o f f , a s e v id e n c e d by
th e n e g l i g i b l e r i s e i n th e c r e e k d r a in i n g th e a r e a mapped a s Ram bler
d u rin g a 1 .5 in c h r a i n f a l l (p ag e 7 1 ).
The c re e k d r a in i n g c l e a r c u t
a r e a s on th e G a r l e t L oberg Complex (C re ta c e o u s b e d ro c k ) showed a p p r e ­
c i a b l e r i s e an d i n c r e a s e i n t u r b i d i t y ( F ig u r e 2 2 ) ,
The B u ll Lake s o i l p r o f i l e n e a r th e C r a i l Ranch ( F ig u r e 6a) i s
fro m an a r e a o f B u ll Lake t i l l mapped a s th e L e a v i t t s to n y loam
com plex.
The L e a v i t t S e r i e s a r e A r g ic C r y o b o r o llis w ith a t y p i c a l
m o l lic e p ip e d o n ( s i g n o f a g r a s s la n d s o i l ) .
The r e p r e s e n t a t i v e p ro ­
f i l e com pares f a v o r a b l y w ith th e p r o f i l e shown i n F ig u r e 6 a , w hich i s
a t y p i c a l B u ll Lake s o i l i n th e a r e a .
The c l a y s o i l ( F ig u r e 20a) n o r th o f th e u p p e r v i l l a g e s i t e
(S 1 9 , T6S, R3E) may be s i m i l a r t o th e K is s ic k ( c la y ) S e r i e s .
The
K is s i c k i s a V e r t i c C r y o b o r o ll w hich i s mapped a lo n g th e G a l l a t i n .
R iv e r s o u th (u p s tre a m ) o f i t s j u n c t i o n w ith th e West F o rk .
The s o i l
was w et a t tim e o f s a m p lin g and s l i c k e n s id e s ( c l a y m i c r o f a u l t s ) w e re n ’ t
e v i d e n t.
M o ttlin g o f th e sam p les may i n d i c a t e t h a t t h i s s o i l i s
-7 9 p e r p e t u a l l y s a t u r a t e d Tfith w a te r and d o e s n ’ t d ry o u t enough t o form
and show s l i c k e n s i d e s .
The K is s i c k i s known f o r i t s v e r t i c a c t i o n
and s l i c k e n s i d e s .
The K is s i c k i s mapped a lo n g th e G a l l a t i n R iv e r , a s m e n tio n e d .
W alsh (1971) h a s mapped t h i s a r e a a s Q u a te rn a ry t e r r a c e s .
H owever,
th e C re ta c e o u s T h erm o p o lis an d Muddy F o rm a tio n s a r e a l s o mapped n e a r ­
by,
The w r i t e r b e l i e v e s t h a t th e K is s i c k and some o th e r f i n e g r a in e d
s o i l s o f t e n occur- b e c a u se o f t h e i r p r o x im ity t o th e C re ta c e o u s s h a l e s .
T h u s, th e s o i l s o f th e s h a le s on th e a n t i c l i n e d e v e lo p e d in th e Koo­
t e n a i F o rm a tio n i n S19, T6S, R3E, may be s i m i l a r t o th e K is s ic k b e c a u se
of s im ila r p a re n t-m a te ria l.
I t a p p e a rs t h a t by m apping th e s h a le
b e d ro c k i n th e a r e a , one c o u ld d e r iv e an a c c u r a te map of p o s s i b le
c la y e y s o i l s , w hich a r e o f te n n o t s u i t a b l e f o r c o n s t r u c t i o n .
NATURAL AREAS
The m a jo r l a n d s l i d e a r e a s (U le ry s L akes a r e a an d th e l a n d s l i d e
t h a t c r o s s e s th e lo g g in g r o a d i n S27, T6S, R3E) a r e u n s u i t a b l e f o r
c o n s t r u c t i o n and h e a v y u s e .
They a r e a r e a s o f ponds an d s m a ll swamps,
a s w e ll a s f o r e s t s an d g r a s s l a n d s .
n ic h e s f o r many a n im a ls and, p l a n t s .
T h ese a r e a s p r o v id e e c o l o g i c a l
They o f f e r th e v i s i t o r e x p e r i ­
e n c e s i n so m eth in g o th e r th a n f o r e s t s and s a g e b ru s h g r a s s l a n d s .
The
w r i t e r b e l i e v e s t h a t th e s e a r e a s a r e e s p e c i a l l y s u i t e d t o be s e t a s i d e
a s n o n - c o n s tr u c t io n a r e a s , w ith n o n -m ec h an ize d t r a v e l o n ly , and h o p es
—80—
t h a t th e y m ig h t b e r e c o g n iz e d a s u n iq u e n a t u r a l a s s e t s an d l e f t a s
such.
B e s id e s p la y in g a v i t a l r o l e i n th e n a t u r a l e c o lo g y o f th e
a re a # th e y c o u ld be e x c i t i n g a r e a s f o r o b s e r v a tio n an d s tu d y .
SUGGESTIONS FOR FURTHER STUDY
F u r t h e r g e o l o g i c a l s tu d y i n th e West F o rk b a s in w ould be v a l u a b le
i n tw o f a c e t s .
One w ould be on s i t e d e t a i l e d i n v e s t i g a t i o n o f p r o ­
p o se d c o n s t r u c t i o n and la n d u s e s i t e s .
A n o th e r w ould b e a s tu d y of
th e v a r io u s n a t u r a l an d c u r r e n t l y o p e r a t in g p r o c e s s e s r e l a t e d t o
E n v iro n m e n ta l g e o lo g y .
I1
2.
3.
4.
I n t h e f i r s t c a te g o r y m ig h t b e :
D e ta i le d i n v e s t i g a t i o n o f th e u p p e r v i l l a g e s i t e and
p ro p o s e d ro ad w ay .
D e ta i le d s tu d y o f th e a c t i v e ro c k g l a c i e r , t o in c lu d e
d e te r m in in g i f i t h a s an i c e c o re and w hat i t s r a t a of
movement is ',
M o n ito rin g th e e f f e c t s o f c o n s t r u c t i o n and u s e in
e n v ir o n m e n ta lly h a z a rd o u s a r e a s .
M o n ito rin g movements o f th e a c t i v e s l i d e c r a c k s n o r th of
th e u p p e r v i l l a g e s i t e .
I n th e seco n d c a te g o r y m ig h t b e :
1.
2.
3.
4,
S tu d y o f p r o c e s s e s o f t a l u s f lo w and s o l i f l u c t i o n .
S tu d y o f a v a la n c h e h i s t o r y by ex am in in g th e a g e s o f
t r e e s on an d n e a r a v a la n c h e p a t h s .
S tu d y o f s o i l f o r m a tio n on d i f f e r e n t p a r e n t m a t e r i a l w ith
common f a c t o r s o f c l i m a t e , r e l i e f , v e g e t a t i o n , an d tim e .
Q u a n t i t a t i v e m easu rem en t o f b i o l o g i c a l , c h e m ic a l and
g e o l o g i c a l m a t e r i a l i n r u n o f f fro m lo g g e d a r e a s on
C re ta c e o u s b e d ro c k .
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sMhMsm'Mm'A‘ F ig u r e 24 . A re a s n o t g e o l o g i c a l l y f a v o r a b l e f o r c o n s t r u c t i o n .
I n c lu d e s p ro p o s e d " N a tu r a l A re a s " , d o es n o t in c lu d e a v a la n c h e
h a z a r d s and s m a ll d e t a i l s .
REFERENCES CITED
—8 3 REFERENCES CITED
Bla c k w e ld e r , E l i o t (1 9 1 5 ). P o s t- C r e ta c e o u s h i s t o r y o f th e m o u n tain s
o f s o u th w e s te r n Wyoming, J o u r . G e o l. , 2 3 . .
H a l l , W. B„ ( 1 9 6 0 a ) . M u ltip le g l a c i a t i o n i n th e M adison an d G a l l a t i n
R an g es, S o u th w e s te rn M ontana, i n B i l l i n g s G eo l. S oc. G u idebook,
I l t h A n n u al F i e l d C o n f ., West Y e llo w s to n e -E a rth q u a k e A re a ,
; H a l l , W. B. (1 9 6 1 )„ G eology o f P a r t o f th e Upper G a l l a t i n V a lle y o f
S o u th w e s te rn M ontana, Unpub. PhD T h e s i s , U n iv e r s it y of Wyoming.
K e e f e r , W. R. and L ove, J . D„, (1956) e L a n d s lid e s a lo n g th e Gros
V e n tre R iv e r , T e to n C o u nty, Wyoming, Wyo. G eo l, A ss n e I l t h Ann.
F i e l d C o n f. G u id eb o o k , J a c k s o n H o le.
7 Kehew, A. W. (1 9 7 1 ). E n v iro n m e n ta l g eo lo g y o f p a r t o f th e West F o rk
B a s in , G a l l a t i n C o unty, M ontana, u n p u b lis h e d Ms. t h e s i s . D ep t,
o f E a r th S c ie n c e s , M ontana S t a t e U n iv e r s ig y , Bozeman.
’ K e r r , P . F . , S tr o u d , R. A. and Drew, I . A. (1 9 7 1 ).- C lay m o b i lit y in
l a n d s l i d e s , V e n tu r a ,. C a l i f o r n i a . , A .A .P .G . B u l l . , V55, N2,
McMannis, W. J . and C hadw ick, R. A. (1 9 6 4 ). G eology o f th e G a rn e t
M ountain Q u a d ra n g le , G a l l a t i n C ounty, M ontana, M ont. B ur, of
M ines and G eology B u l l . , 47 p a g e s ,
M o rris o n , R . B. (1 9 6 5 ). Q u a te rn a ry S o i l s , V II C o n g ress INQUA, V 1 0 ,
D e s e r t R e s e a rc h I n s t i t u t e , R eno, N evada.
P a t t e n , D. (1 9 6 3 ). V e g e ta tio n a l p a t t e r n i n r e l a t i o n t o en v iro n m e n t i n
th e M adison R ange, M ontana, E c o lo g ic a l M onographs, V 3 3 , N 4 .
P e a l e , A. C. (1 8 9 3 ). D e s c r ip ti o n o f th e T h ree F o rk s S h e e t, U .S . G e o l.
S u rv ey G eo l. A t l a s F o l i o 2 4 .
P i e r c e , K. L. (1 9 7 0 ) . G l a c i a t i o n o f n o r th e r n Y e llo w sto n e N a tio n a l
P a r k , i n A b s t r a c t s AMQUA F i r s t M e e tin g , Y e llo w s to n e N a tio n a l P a rk
and Bozeman, M ontana.
P o t t e r , N. (1 9 6 7 ). Rock g l a c i e r s and m ass w astag e i n th e G alen a C reek
a r e a . N o rth e rn A b sa ro k e M o u n ta in s, Wyoming, U .S . Army, N a tic k
L a b ., N a tic k , M ass.
—84—
P o t t e r , N. (1 9 6 9 ). T re e r i n g d a tin g o f snow a v a la n c h e t r a c k s and th e
geo m o rp h ic a c t i v i t y o f a v a la n c h e s . N o rth e rn A b saro k a M tns„ , Ity o .,
i n TJ.S, C o n tr ib u tio n s t o Q u a te rn a ry R e s e a rc h , ed by S. A. Schumm
an d W. C. B ra d le y .
Richm ond, G, M. (1 9 6 5 ). The g l a c i a t i o n o f th e Rocky M o u n ta in s, in
Q u a te rn a ry H is to r y o f th e U .S .,, INQUA V II C o n g re s s , ed by H„ E.
W right an d D, G. F r e y .
R ichm ond, G. M. (1 9 7 0 ). G l a c i a l h i s t o r y o f th e Y e llo w s to n e Lake
b a s i n , i n A b s t r a c t s AMQUA F i r s t M e e tin g , Y e llo w s to n e N a tl. P a rk
an d Bozeman, M ontana.
Sw anson, R. W. (1 9 5 0 ) . G eology o f p a r t o f th e V i r g i n i a C ity and
E ld r id g e Q u a d ra n g le s , M ontana, U. S . G eo lc S u rv ey Open F i l e
Summary R p t. , 12 p a g e s .
S h a rp e , C, F , S . (1 9 3 8 ). L a n d s lid e s an d R e la te d Phenomena, A S tu d y
o f Mass Movements o f S o il and R ock, New Y ork.
T h o rn b u ry , W. D. (1 9 5 4 )«
P r i n c i p l e s o f G eom orphology, New Y ork.
USDA, SCS a n d M ont. Ag, E x t, S t a . , ( W in te r , 1 9 7 0 ),
M easurem ents f o r M ontana.
US D ep t, o f Commerce, W eather B ureau (1 9 6 3 -1 9 7 1 ).
Datg,, M o n tan a.
US F o r e s t S e r v ic e , USDA, (1 9 6 8 ).
Summary o f Snow
C lim a to lo g ic a l
Snow A v a la n c h e s , Ag. Handbook 194.
V a rn e s , D. J . (1 9 5 8 ).. L a n d s lid e ty p e s an d p r o c e s s e s , i n L a n d s lid e s and
En g in e e r in g P r a c t i c e , N a tl. R e s e a rc h B o ard , Sp. R p t. 2 9 , ed by
E. B. E c k e l, N at. A cad. S c i. - N a tl. R es. C o u n c il Pub. 544.
1W a h rh a ftig , C0 and Cox, A. (1 9 5 9 ). Rock g l a c i e r s i n th e A la sk a R ange,
G e o l. S o c, Am. B u ll . 7 0 , p . 383 436,
‘‘W alsh, H. T . (1 9 7 1 ). Q u a te rn a ry G eology o f th e E a s t P o r tio n of West
F o rk B a s in , G a l l a t i n C o u nty, M ontana, Unpub. Ms t h e s i s , M ontana
S t a t e U n i v e r s i t y , Bozeman.
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-8 5 W ils e y , J» A. (1 9 4 8 ), G eology o f th e G a l l a t i n V a lle y A re a , u n f in i s h e d
PhD T h e s i s , P r in c e t o n U n iv e r s it y .
APPENDIX
-8 7 STRATIGBAPHY
The f o llo w in g i s a sum m ation from Swanson (1 9 5 0 ), H a ll (1 9 6 1 ),
McMannis an d Chadwick (1964) an d Kehew (1 9 7 1 )„ As such i t i s g e n e r­
a l i z e d in f o r m a tio n fro m th e s tu d y a r e a , fro m H a l l 's a r e a t o th e s o u th ,
and from th e G a rn e t M ountain Q u ad ran g le (McMannis and C hadw ick, 1964)
t o th e n o r t h e a s t . The w r i t e r d id n o t a tte m p t any f i e l d s tu d y o f th e
s t r a t i g r a p h i c s e c t i o n o ld e r th a n th e Q u a te rn a ry f e a t u r e s .
P re -C a m b ria n
The c o r e o f th e S p a n is h P eak s c o n s i s t s o f P re-C am b rian
m e ta -s e d im e n ts i n th e fo rm o f s c h i s t s an d g n e i s s e s , w ith amphi­
b o l i t e , p e g m a tite an d b a s i c d ik e r o c k s .
C am brian
F la t h e a d S a n d sto n e
50-100 f e e t o f b a s a l q u a r t z i t e , g r a y is h g re e n s a n d s to n e ,
w ith an u p p e r s i l t s t o n e s a n d s to n e seq u en ce
W olsey S h a le
60 f e e t o f n o n r e s i s t a n t s h a l e , s h a ly s a n d s to n e and
s h a ly lim e s to n e
G a l l a t i n F o rm a tio n
600 f e e t o f lim e s to n e an d d o lo m ite w hich i s d iv id e d by
McMannis an d Chadwick (1964) i n t o :
M eagher L im esto n e 400 f e e t o f t h i n bedded m o ttle d
lim e s to n e
2 ,0 0 0 f e e t o f g re e n f i s s l e s h a le
P a rk S h a le
P ilg r i m L in e s to n e 200 f e e t o f medium b edded t o
m a ss iv e lim e s to n e
Red L io n Firf.
c o n s i s t i n g o f th e Dry C reek
s h a le an d an unnamed u p p e r c a r b o n a te
O rd o v ic ia n
B ig h o rn D o lo m ite
80 f e e t o f f i s s i l e lim e s to n e and m a ss iv e d o lo m ite , th e
d o lo m ite i s r e s i s t a n t and h a s a m a ssiv e a p p e a ra n c e .
S ilu ria n - n o t p re se n t
D evonian
J e f f e r s o n L im esto n e
400 f e e t o f d o lo m itic lim e s to n e
T h ree F o rk s S h a le
100 f e e t o f d o lo m itic s h a le an d le d g e fo rm in g lim e s to n e
M is s is s ip p ia n
L o d g ep o le L im esto n e
400 f e e t r e s i s t a n t medium t o t h i n bedded c l i f f fo rm in g
lim e s to n e
M is s io n Canyon L im esto n e
400 f e e t o f medium t o m a ss iv e ta n c l i f f fo rm in g lim e s to n e ,
c l i f f s o f te n s t a i n e d by th e r e d Amsden above
Amsden Fm.
50 f e e t o f r e d s h a le an d s i l t a s s o c i a t e d w ith th e
M issio n Canyon L im esto n e
P e n n s ly v a n ia n
Q u ad ran t F o rm a tio n
270 f e e t of c le a n o r t h o q u a r t z i t e w hich fo rm s y e llo w -w h ite
c liffs
P erm ian
P h o s p h o ria F o rm a tio n
140 f e e t o f p h o s p h a tic s h a l e , s a l t and p e p p e r s a n d s to n e ,
a n d c h e r t b e d s , u s u a l l y fo rm s c l i f f s o r t a l u s s lo p e s
T ria s s ic
Dinwoody F o rm a tio n
80 f e e t o f t h i n bed d ed lim e s to n e and s i l t s t o n e w hich
w e a th e rs t o d a rk brown t o t a n
J u ra s sic
S aw to o th Fm,
120 f e e t o f g r a y t h i n bedded lim e s to n e , c a lc a r e o u s s h a le
an d p e b b ly s a n d s to n e
R ie rd o n Fm.
50 f e e t o f le d g e fo rm in g o o l i t i c lim e s to n e
S w if t Fm.
9 0 -f e e t o f c a lc a r e o u s s a n d s to n e an d o o l i t i c lim e s to n e
M o rriso n Fm,300 f e e t o f c l a y s t o n e , s i l t s t o n e and b u f f c o lo r e d lim e ­
s t o n e , o f t e n c o n t r i b u t e s t o l a n d s l i d i n g and i s seldom fo u n d
o u tc ro p p in g
C re ta c e o u s
K o o te n a i Fm,
400 f e e t c o n s i s t i n g o f a lo w er m a rin e s a l t an d p e p p e r
s a n d s to n e , a m id d le r e d c l a y s t one and f o s s i l i f e r o u s lim e ­
s t o n e , an d an u p p e r r e s i s t a n t q u a r tz s a n d s to n e
—89“
T h erm o p o lis S h a le
150 f e e t o f d a rk f i s s i l e s h a le and s i l t s t o n e
Muddy S a n d sto n e
50-200 f e e t • o f t h i n to medium bed d ed d i r t y g ra y s a n d s to n e
A lb in o Fm,
300 f e e t o f v o lc a n ic c l a s t i c se d im e n ts w ith c la y s to n e
b e n t o n i t e , s h a l e , a s h , and t u f f
U pper C re ta c e o u s U n d i f f e r e n t i a t e d
up t o 8 ,0 0 0 f e e t o f m a rin e and n o n -m arin e e l a s t i c s
T e r t i a r y (e x p o s e d e ls e w h e re i n th e G a l l a t i n and M adison R anges)
L iv in g s to n Fm,
500-800 f e e t o f v o lc a n ic s and r e l a t e d s e d im e n ts (P a le o c e n e ? )
S p h in x C o n g lo m erate
(E ocene) c o n g lo m e ra te and s a n d s to n e o f S p h in x M tn0
Specim en C reek Fm.
4 ,0 0 0 f e e t o f v o lc a n ic s e d im e n ts w ith a s s o c i a t e d
p e t r i f i e d wood (E o c e n e -O lig o c e n e ? )
Q u a te rn a ry
The num erous s u r f i c i a l d e p o s it s o f f l u v i a l , g l a c i a l and la n d ­
s l i d e o r ig in ,- an d w eld ed t u f f , a r e d e s c r ib e d i n d e t a i l i n t h i s
p ap er.
Ig n e o u s
H a ll (1961) r e c o g n iz e s e i g h t i n t r u s i v e s i n th e U pper G a l l a t i n
V a lle y . The Lone M ountain l a c c o l i t h i s th e n o rth e rn m o s t o f
th e s e b o d ie s , an d h a s been m e n tio n e d i n th e m ain body o f t h i s
p a p e r , Ho d e t a i l e d work h a s been done on i t .
E x t r u s iv e r o c k s
in c lu d e some b a s a l t i c v o lc a n ic n e c k s i n th e G a l l a t i n Range e a s t
o f W est F o rk an d th e Q u a te rn a ry w eld ed t u f f s fro m th e Y ellow ­
s to n e a r e a .
V
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ENVIRONMENTAL
‘
GEOLOGY OF THE WEST FORK B A S I N
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