STRATIGRAPHY AND CORRELATION OF
1,HDDLE DEVONIAN STRATA IN THE JASPER SAG, NORTHEASTERN INDIAr-TA
by
William D. Rebuck
Submi tted to Dr. R. William Orr and the Honors Irogram,
Ball State Uni versi ty, Mun61e, Ind ia..l1a in .ful.fillment o.f
ID 499, Senior Honors Thesis.
June 1, 1970
;::'
- f. Coi i
n1e~~,1 :~
l-D
""'l
i..i '~,
cJ.' ;
,Cf'lO
Od~
• 1\ 7";
I recommend this thesis
o~
~or
acceptance by the Honors Program
Ball State University for graduation with honors.
Thesis Adviser
nAJ~( I.
~9.t?)
Geography-Geology Department
ICf70
CONTENTS
Introduction. • • • • •
• •
Page
• • • • •
• • • • • • • .1
Figure 1. • • • • • • • • • • • • • • • • • • •
• • • 2
Geologic structure
•••••••••••
• • • • • •
Figure 2 • • • • • • • • • • • • • • • • • • • • • • • •
Devonian stratiGraphy OI northern Indiana • • • • • • • • 5
Devonian rocks of Jasper County • • ••
Figure 3.
Figure 4
The
........
•••
conodo~'lt
•••
•••
10
. . . . . . . . . . . • 11
• • • • • • • • • • • • • • • • • • • 12
fauna • • • • • • • • • • • • • • • • • • • 13
Table 1 • • • • •
Table 2 • • • •
• • • • • • • • • • • • • • • • • •
.14
• • • • • • • • • • • • • • • • • • • .15
Correlation • • • • • • • • • • • • • • • • • • • • • • .16
Figure 5
• • • • • • • • • • • • • • • • • • •
• • • 18
References cited • • • • • • • •
•
• • • • • • •
• 19
INTRODUCTION
This paper concerns research pertaining to the
investigation
o~
Devonian strata in Jasper County near
Rensellaer, Indiana (Fig. 1). Strata
o~
Middle Devonian age
are exposed in the Northern Indiana Stone Inc. quarry (locality
1) at Pleasant Ridge and at the W. C. Babcock Construction
Company quarry at Rensellaer (locality 2). At both localities
Upper Devonian black shale is absent and the bedrock
sur~ace
is on the llIiddle Devonian carbonates. These rocks uncomormably
overlie Silurian carbonates and crop out in the structural
depression known as the Jasper Sag. The Mid6le Devonian strata
have
hereto~ore
been unassigned as to geologic
~ormation.
Field work and sample gathering was done in the autumn
and winte!r
o~
1969. Dr. R. William Orr
o~
the Department
o~
Geography and Geology, Ball State University, accompanied the
writer on several
~ield
excursions and assisted the writer
in numerclus ways. For this lowe him a debt
o~
gratitude.
It should. be noted that this paper is an outgrowth
paper to be prepared by Dr. Orr
~rom
the Indiana Academy
o~
~or
o~
which a research grant
Science was awarded. My gratitude
is also Elxtended to the Indiana Geological Survey who
did the initial processing
recovery
o~
conodonts.
a
o~
the rock samples
~or
the
2
JASPER
COUNTY
R
R. 6
2
w.
1
R. 5
w.
T. 29 N.
X
oL--l----l
10
20
30
!
+0
I
SO H'
I
Figure 1. Map of Jasper County showing collecting localities of
Middle Devonian dolomite Wlits in the Jasper Sag.
~
tS
3
GEOLOGIC STRUCTURE
The Cincinnati Arch is an intracratonic positive
structure that trends northwest-southeast
~rom
east-central
Indiana to Lake County. The Arch separates the Illinois
Basin to the southwest
northeast. Most
o~
~rom
the Michigan Basin to the
the Cincinnati Arch is a plat.form with
gentle monoclinal .folds on its
~lanks.
In the crestal area of
the Arch the dip of the strata is very small or imperceptible
in the outcrop; however, on its
~lanks
the dip is 35 .feet
or more per mile (Pinsak and Shaver, 1964).
The crestal area
o~
the Arch is interrupted by two
depressions, the Logansport Sag and the Jasper Sag (Fig. 2).
Both depressions trend northeast-southwest and have structural
relie.f of generally less than 100 .feet. The Jasper Sag is the
more northern o.f the two depressions and is situated in
Newton, Jasper, and Starke Counties. The Logansport and
Jasper Sags are separated by a culmination or positive
anomaly called the FranceSVille Dome (Pinsak and Shaver, 1964),
which is located in White, Jasper, l'ulaski, and Fulton
Counties.
4
.,
I
-
J,
~
,
,
o
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z
~
i'
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CL,,,rLl/r "'~''Wal
C'Olu rT ,
If'
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th,'I"
:1
~',
;.
rn~C:1
25C·
C;t:O
40 MI'rs
__ ~.J
Itf-I
f .. 1:"1
'- r ....~.
oj' tile 'frell ton Li:rrestol,e an -, !lamed structural
fea.turec an 1 localities. Str'ucture fro::!
1952.
awson,
5
DEVONIAN STRATIGRAPHY OF NORTHERN INDIANA
Devonian strata in northern Indiana were first
recogniz~~d
by Owen (1839) who compared carbonate rocks
underlying the Antrim Shale in Cass County with similar
rocks in southern Indiana. The usage of nomenclature for
Devonian strata in northern Indiana was summarized by
Thornbury and Deane (1955). In the same report a comparison
of the l:i thologies of Devonian strata of Miami County was
made with the Traverse Group of Michigan. It was noted that
the northern Indiana Devonian carbonate section appeared
more correlative with the Traverse Group than with the North
Vernon Limestone of southern Indiana and the Illinois Basin.
Northeast of the crestal area of the Cincinnati Arch,
the pre-:Pleistocene subcrop of Devonian strata in Indiana
extends as a belt having an east-west orientation along the
southern flank of the Michigan Basin. The strata in this
belt attain a maximum thickness of about 200 feet. In
the Logansport Sag (Cumings and Schrock, 1928) Middle
Devonian strata lithologically more closely resemble
equivalent strata of the Michigan Basin than those of the
Illinois Basin (Orr, 1969). In the Jasper Sag Devonian
rocks extend across the broad crest of the Cincinnati Arch
into the Illinois BaSin, where they lie at the bedrock
surface and extend in a northwest-southeast belt along the
northeastern flank of the Illinois Basin.
In northern Indiana there are two main divisions of
!vUddle D.avonian carbonate rocks: the Detroit River Formation
6
(SchneidElr and Keller, 1969) and the Traverse Formation.
The Detroit River Formation is separated f'rom the overlying
Traverse Formation by an unconi'ormity. These two units
are correlative with the Detroit River Group and Traverse Group
of' Michigan, respectively.
The Detroit River Formation unconforulably overlies the
Salina Formation (Silurian) in the northern part oi' the
state. It lithologically resembles the Lucas Dolomite of'
Michigan and pinches out westward in Porter County and
has its f30uthernmost extension in Adams and Cass Counties.
In the northernmost part oi' Indiana, the Detroit River Formation
attains a thickness oi' 140 i'eet (Pinsak and Shaver J 1964).
It ranges in thickness i'rom 12 to 40 i'eet in cores stuoied
by Orr (1967).
Devonian strata are .found overlying every major component
part oi' the Salina and Wabash ,1;'ormati0tlS (Pinsak and Shaver,
1964). The Silurian-Devonian inter.face is uncon.formable
throughout the area with no Lower Devonian strata present.
None of' the faunas recognized to be (' ei'ini tely Devonian have
been shown to be older than Middle Devonian in age. This
relationl3hip is demonstrated in the Geneva Dolomi te J Fendleton
SandstonE!, and Je.fi'ersonville Limestone of the southern
Indiana outcrop area.
In many localities it is dii'ficult to distinguish
Silurian i'rom Devonian rocks. Detailed faunal and lithologic
studies
~~e
required to elucidate the age relationships
in these areas. In areas where the Wabash Formation is the
7
uppermost Silurian unit, argillaceous, silty dolomite
is domiruUlt in eastern portions of the area and coarse
textured:, vUggy or cherty dolomite in western sections.
In northern Indiana, north o.f the crest of the
Cincinnati Arch, basal Devonian rocks most commonly consist
o.f gray to light brown, .fine-grained to dense, more or
less arenaceous dolomite. This basal Devonian zone generally
averages about 10 feet in thickness. This arenaceous zone
is signi:ficant in the identification of the Silurian-Devonian
boundary. The arenaceous zone grades upward into more
normal tan and gray, granular, somewhat argillaceous dolomite
and lime:stone. The basal Devonian arenaceous zone is
probably equivalent to part of the Detroit River Group
of
Michil~an,
most likely the Lucas Dolomite. This sandy
zone is included with the overlying carbonate rocks in
the manner o.f Landes (1951) who included the Sylvania Sandstone
in the D,etroit River Group.
The Detroit River Group in Michigan is composed of four
formations. They are in ascending order: Sylvania
S~ilostone,
Amherstburg Formation, Lucas Dolomite, and Anderdon Limestone.
This nomenclature for the Detroit River Group was proposed
by Ehlers (1950). The middle portion of the Detroit River
Formation contains dolomite, dolomitic limestone, evaporites
(gypsum and anhydrite), ano thin shale partings in order
of decreasing abundance. In the upper portions of the
Detroit
:~iver
Formation the rocks are generally gray to
tan, subli thographic to lithographic li'r.estone. This upper
8
portion resembles similar beds in the Anderdon Limestone
that lies at the top of' the Detroit River Group of'
Michigarl. The Detroit River group thins to the south and
is composed o:f carbonates, thin shale partings and evaporites.
Lithographic limestone is f'ound near the top of' many sections.
The AmhElrstberg Formation of' the Detroit River Group pinches
out southward and does not enter Indiana. It is likely
therefore, that the Indiana portion corresponds only to the
Lucas Dolomite.
ThEl Traverse Group (Middle Devonian) of Michigan
consistEJ of about 10 formations. A complete discussion of
the Traverse Group in its type area near Thunder Bay,
i¥1ichigan can be found in Warthin and Cooper (1943). In
northernmost Indiana, southward thinning rocks equivalent
to the
~~raverse
Group, are found overlying the Detroit River
Formation. It is probable that these younger rocks extend
farther south than the Detroit River in which case the name
TraversH Formation could be extended to strata in Howard,
Cass, },itami, and Carrol Counties.
In northern Indiana strata equivalent to portions of
the Traverse Group have been called the Jeffersonville
Limestone (lower j,lIicldle Devonian), Logansport Limestone
(Hamiltonian in age), Sellersburg Limestone (also Hamiltonian
in age, and the Hamilton Group (Thornbury and Deane, 1955).
In portions of Jasper, Benton, Tippecanoe, Newton, and
White Counties r.1iodle Devonian strata consist of dark-brown,
medium to coarse-grained, detrital dolomitic limestone with
arenaceous, argillaceous, ana brecciated faCies. These rocks
9
appear to be correlative with the Traverse Group and are
most likely Hamil ton in age (IJinsak and Shaver, 1964).
The Traverse Formation of northern Indiana is a
carbonat{~
succession consisting predominantly of limestone,
argillacE~ous
limestone, dolomite, and thin shale beds in
oreer of decreasing abundance. Cooper and Warthin (1941)
correlated similar bens which crop out near Logansport with
the Hamilton Group of New York and proposed the name
Logansport Limestone for these rocks. In the same report
similarities of the Logansport Limestone with the Four Mile
Dam Limestone was noted.
Studies of conodont successions show that the northern
Indiana
~eraverse
Formation includes strata equivalent to a
sub-Squaw Bay Limestone portion of the Traverse Group o.f
Michigan (Orr, 1967).
Orr (1969) extended the name Traverse Formation to
25 feet of strata in the Logansport Sag. Traverse rocks of
the Sag and those of the Michigan Basin of equivalent late
Middle DHvonian age have similar lithologies, similar
depositional histories, and have almost identical conodont
faunas.
~~he
strata of the Logansport Sag have previously
been separated into the Little Rock Creek Limestone, Logansport
Limestone, and Miami Bend Formation in descending order,
by Cooper and Phelan (1966).
10
DEVONIAN ROCKS OF JASPER COUNTY
Middle Devonian rocks at localities 1 and 2 are almost
exclusively fine-grained, dark gray dolomite. Figures 3 and
4 are stratigraphic sections from localities 1 and 2
respectively.
Approximately 33 feet of I'fliddle Devonian strata are
exposed at the Northern Indiana Stone Inc. quarry (locality
1).
~his
quarry is located on the north side of state road
114, east of Pleasant Ridge, Indiana, C S
i,
NE
i,
sec. 19,
T. 29 Ii., R. 6 W. (211cCoysburg quadrangle).
About 11 feet of Midc11e T)evonian rocks are exposed
at the W. C. Babcock Construction Company quarry (locality 2)
on the southeast edge of Rensellaer, Indiana, SE
!, SE i,
sec. 30, T. 29 N., R. 6 TN. (Rensellaer quadrangle).
The strata at both localities display very similar
lithologies. The most notable c1ifference is the presence of
a 4 inch shale unit at locality 2. The carbonates at locality
2 were much less pyritiferous than at locality 1. A greater
abundance of phosphatic .fish bone fragments was noted in
the processed heavy mineral samples from several beds at
locality 1.
All cited topographic maps are from the U. S. Geological
Survey 7.5 minute series (1:24,000).
11
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gray; thin bedded, weathers to
light brown; contains molds and
casts of fossils (brachiopods,
corals, stromatoporoids), scattered
vugs and slitlike cavities previously occupied by .fossile (brachiopo ': sj
pockets of massive white calcite,
dolomite crystals on weathered
surfaces; limonite, pyrite and
marcasite; lowermost part is
argillaceous. 6' 10"
./
/
./
./ /.
LL'
"
./
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L~
L~
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o Dolomite, fiDe-grained, very dark
./'\
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.......
10
[f}
'~
(.)
[f}
11
Dolomite, as above; weathers to
medium brown with contrast to unit
above; upper boundary is prominent
undulating bedding plane; upper
part contains pockets of ~casite
20 and is distinctly lisonitic;
argillaceous in part; intervals 12
and 13 are conspicuously fossiliferous with brachiopods &Ad
colonial corals; thin bedded in
upper half becoming increa.singly
thicker towards toe base. 25' 6"
25
12
/-'L-/-/-~
-/-/-/-
,/
////
L
/
/
/
/-/-/-/-/-
30
//// /
/
/
/
./
./
/
././
/./ . /
-Dolomite, very :fine grained to
sublithoGra~hic; grades ~rom pure
/-/-/-/and
laminated at the top to distin~
./
-" - L - / - . /
35 ly argillaceous and platy in lower
part; to several feet above quarry
floor. 2' 4"
Fig. 3-Stratigraphic section of Midr'lle Devonian
strata at the Northern Indiana Stone Inc.
quarry, Pleasant Ridge, Indiana.
./
L
./
./-
12
,......
7
/
/
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7
-/
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7~
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fine to medium grained,
aark gray weathering to brown,
sparingly fossiliferous (mostly
corals), argillaceous in part
with 4" shale 38"-42" below
top; measured from highest
bedrock to top quarry bench;
base of unit is several feet
above oase of Devonian strata
11'
•
////
Dolomite~
:-I
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-,
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7
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-/-/-/-/-/-.
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7
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L
/
/
/
/
/
/
10'
/
Fig. 4-Stratigraphic section of Middle Devonian strata
at the W. C. Babcock Construction Company quarry,
Rensellaer, Indiana.
13
THE CONODONT FAUNA
:';liddle Devonian strata o£ the Jasper Sag display a
pauci ty o.f conodont s:f€ cimens. Approximately 200 specimens
were recovered £rom 19 samples averaging 1 kilogram in weight.
Due to the £ragmentary, poorly preserved state o£ many o£
the speci:nens, specific taxonomic assignment was illpossible
in many cases.
The strata o£ the Jasper Sag have a characteristic
association o£ upper l'Uddle Devonian conodonts. In the material
studied, platform conodont species are represented by
Icriocus latericrescens, l..£!:iodus expansus, Icriodus
~iformis,
and Polygnathus varcus. Cone conodonts identi£ied are Acodina
curvat~
and
Hindeodella
B~lodella
devonicus. The only bar recovered is
~
The conocont faunas at localities 1 and 2 are identical
except for the absence o£ Belodella devonicus and Icriodus
cymbilormis at locality 2. Icriodids are by far the most
prolilic constituent o£ the conodont faunas with Icriodus
latericrescens latericrescens and Icriodus expansus predominant.
Tables 1 and 2 show the stratigraphic distribution
of conodont species at localities 1 and 2 respectively. It
can be Obl:lerved £rom the tables that the exposed Devonian strata
at both quarries lie within the }olygnathus varcus Zone
(Givetian). This zone is characterized by the association
of Polygnathus varcus and Icriodus latericrescens
latericresc~.
14
Table 1. Stratigraphic distribution o£ conodont species
at the Northern Indiana Stone Inc. quarry.
Conodont Species
Icriodus
cymbi£o~nis
L.. latericrescens
Sample
(top) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
X
X X
X X
I.:. eXI1ansus
Acodina
X X X
X
~vat§l:
Hindeodella
§.12.!.
X
X
X
X
X
Po l;y:gnathus varcus
X
Belodella devonicus
X
X
15
Table 2. Stratigraphic distribution of conodont species
at the W. C. Babcock Construction Company quarry.
Conodont Species
Sample
(top) 1 2 3 4
Icriodus expansus
~
latericrescens
Acodina curvata
x
xX
X
X
X
X X
Polygnathus varcus
X
Hindeodella
X
..§.ll.=..
16
CORRELATION
From the conodont faunas previously described it has
been shown that the Devonian strata of the Jasper Sag lie
within the polygnathus varcus Zone
Orr (1969) extended the name Traverse Formation to
25 feet o:f strata in the Logansport Sag. The Miami Bend
Formation, Logansport Limestone, and Little Rock Creek
Limestone are downgraded to the rank of lithofacies. These
Devonian strata lie between subjacent Silurian strata and
the superjacent New Albany Shale.
The conodont £aunas £rom the Traverse Formation o£
the Logansport Sag show that two conodont zones are present
there. The lower zone is marked by the presence o£ Icriodus
latericrescens
!..atericre~q~~
and the upper is the ;!?olye;nathu.Q
varcus Zone which contains both Icriodus laterierescens
and Polygnathus varcus. The lower portion of the Traverse
rocks of the Sag (i.e. the Miami Bend and the lower part o£
the Logansport Lithofacies) lie within the Icriodus
latericrescens later1crescens Zone below the lowest position
af Polygnathus yarcus. The upper portion of the Traverse
Formation (i.e. the upper part of the Logansport Lithofacies
and the Little Rock Creek Lithofacies) lie within the
Polygnathus varcus Zone.
In northern Indiana the Traverse Formation unconformably
overlies the Detroit River Formation and lies within the
Icriodus latericrescens later1crescens and Polygnathus
varcus Zones. In the Michigan Basin o£ northern Indiana
17
the lower part of the Traverse Formation lies within
the zone of Icriodus
latericres~
latericriscens while
the upper part lies within the F'olygnathus varcus Zone.
(Orr, 1967).
In southern Inc1iana the Beechwood Member of the North
Vernon Limestone lies on the intertonguing Speed and Silver
Creek Members of the North Vernon Limestone. The Beechwood
Member lies within the Iolygnath!!§. varcus Zone (Orr and
}'ollock, 1968). The superjacent basal limestone of the New
Albany Shale in southern Indiana lies within the Schmidtognathus hermanni-t.Q.lygnathus cristatus Zone and occupies
a problematical position between the !iliddle and Upper
Devonian (Orr and Klapper, 1968).
The conodont fauna of the Beechwood Member contains as
important elements Polygnathus varcus, F. linguiformis, and
Icriodus latericrescens latericrescens as well as a few
specimen~3
of
~
beckmanni,
~ foliatu~
and P.? variabilis.
The presence of the latter three taxa suggests that the
Beechwood Member is in the upper part of the Polygnathus
varcus Zone.
Fi~~re
5 shows the biostratigraphic equivalence of strata
in the Jasper Sag with units in the Logansport Sag, the rocks
of the Michigan Basin of northern ano with Middle Devonian
strata in the Illinois Basin of southern Indiana.
18
.I
NORTH
AMERICAN
JASPER
SAG
LOGANSPORT
SAG
CONODON~I
ZONES
FOLYGNATHUS
VARCUS
NORTHERN
INDIANA
MICHIG Al1
BASIN
BEECHWOOD
MEMBERNORTH
VERNON
LIMESTONE
UNDIFFERENTIA.TED
UPPER
MIDDLE
DEVONIAN
SOUTHERN
INDIANA
ILLINOIS
BASIN
TRAVERSE
FORUTION
~
At--------I
A
H
21
TRAVERSE
FORMATION
ICRIODUS
LATERICRESCENS
LATERICRESCENS
SILVER
CREEK
MEMBER-
Figure· 5.· ·Correlation of Devonian strata of' Jasper County
with equivalent units in Logansport, northern Indiana
and southern Indiana.
19
REFERENCES CITED
Cooper, G. A. and Vlarthin, A. S., 1941: New Uiddle Devonian
stratigraphic names: J. Washington Acad. Sci., v. 53,
p. 1729-1794.
Cooper, G'. A., and Phelan, Thomas, 1966: Stringocephalus
in the Devonian of Indiana: Smithsonian Misc. ColI.,
151 (1), 20 p.
Cumings, E. R., and Schrock, R. R., 1928: The geology of the
Silurian rocks of northern Indiana: Indiana Dept. of
Conservation Pub. 75, 226 p.
Dawson,
~:.
A., 1952: Map showing generalized structure of
TrEmton Limestone in Indiana: Indiana Geol. Survey
111isc. Llap 3.
Ehlers, G.
1,1.,
1950: Revised classification of the Middle
Devonian Detroit River Group (abs.): Geol. Soc. America
Bull., v. 61, p. 1455-1456.
Landes, K. K., 1951: Detroit River Group in the IUchigan Basin:
U. S. Geol. Survey Circ. 133, 23 p.
Orr, R. VI., 1967: Conodonts froiG Middle Devonian strata in
the Michigan 13asin: Unpub. Fh.D. thesis, Indiana Univ., 169 p.
Orr, R. W., and IQapper, Gilbert, 1968: Two new conodont
species from middle-Upper Devonian boundary beds of
Ind:iana ancl New York: Jour. Paleontology, v. 42, p. 1066-1075.
Orr, R. W., and Pollock, C. A., 1968: Reference sections and
correlation of Beechwood ;\jember (North Vernon Limestone,
illidl~le
Devonian) of southern Indiana and northern Kentucky:
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20
Orr, R. W.,1969: Stratigraphy and correlation of Middle
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the State of Indiana, made in the year 1338, in conformity
to an order of the legislature:
Indianapolis, Osborn and Willets, 54 p.; (revision)
Continuation of a report of a geological reconaissance
of the State of Indiana, maoe in the year 1838, in conformity
to an order of the legislature:
Indl.anapolis, John C, Walker, 69 p., 1859.
Pinsak, A. P., and Shaver, R. H., 1964: The Silurian formations
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Schneider, A. F., and Keller, S. J., 1969: Geologic map of the
Chicago lOX
20 quadrangle, Indiana, Illinois, and !Uchigan,
showing bedrock geology ana unconsolidated deposits:
Indj.ana Geol. Survey Regional Geol. Map 4.
Thornbury, W. D., and Deane, H. L., 1955: The geology of Miami
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Warthin, A. S., and Cooper, G. A., 1943: Traverse rocks of
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