ANALYSIS OF MISSISSINEWA SHALE-LISTON
CP£EK LIMESTONE CONTACT IN NORTHEASTERN INDIANA
A THESIS
SUBMITTED TO THE HONOR'S COLLEGE
IN PARTIAL FULFILLMENT OF THE REQUIREMENTS
for the
HONOR'S PROGRAM
by
L. DOUGL..4S MCKEE
Adviser - Dr. Harlan H. Roepke
/paz:
~
01 L-C;;~J/.~~/<1L.
/
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BALL STATE UNIVERSITY
MUNCIE, INDIANA
MAY, 1983
.-
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LI>
ACKNOWLEDGEMENTS
I would like to take this opportunity to thank all those
who aided in this study. Special thanks is offered to'Dr.
Harlan H. Roepke, Honors Thesis advisor, for his aid in the
preparation and editing of this manuscript. Special thanks go
to Dr. Walter H. Pierce, who suggested this particular project. Sj_ncere appreciation is also extended to the Ball State
DepartmEmt of Geology which provided research facilities and
to the Student-Faculty Research Committee which provided
funding for this project in the form of an undergraduate
research grant.
My appreciation is also extended to Dr. Henry E. Kane,
Dr. R. William Orr, and Dr. Alan Samuelson for all the geologic knowledge they have imparted to me over the past four
years. And of course, I wish to thank the Ball State Honors
College for the stimulus for this entire research project.
,-
l'ABLE OF CONTENTS
Page
I.
IN'TRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
'I.
1
A. Purpose of Study........ . . . . . . . . . . . . . . . . . .. .. . . . . . .. . . .... 1
B. Significance ......................................................................... 8
C. Selection of Field Locaclities ................... 8
II.
GEOLOGIC SETTING
A. Structural Setting ............................................................ 12
B. Stratigraphy of Wabash Formation ................. 15
C. Paleogeographic Setting .......................... 18
D. Depositional Model ............................... 18
III.
FIELD METHODS AND LABORATORY PROCEDURES
A. Field Methods and Sampling ....................... 20
B. Laboratory Procedures ............................ 20
1 . Insoluble Res id ue Analys is ................... 21
2. Pipette Analysis ............................. 21
C. Procedure Reliability ........•................... 24
IV..
INTERPRETATION .
V.
CONCLUSIONS ....................................................... 34
VI •
REFERENCES CITED ••..••.••••••.••••.•••..••.•.•••.••• 35
VII.
APPENDIX A (Pipette Analysis Data Form) ............. J7
I
......................................
26
VIII. APPENDIX B (Stratigraphic Distribution of Total
Detritus (percent insoluble) and Silt/Clay Ratios ... J9
---
IX.
APPENDIX C (Stratigraphic Distribution of Silt/
X.
APPENDIX D (Stratigraphic Distribution of Clay/
XI.
APPENDIX E (Paleogeographic Setting of North
America During Silurian ............................. 50
Carbona te Ra tics) ...................................... 44
Carbona te Ra tics) ...................................... 47
ANALYSIS OF MISSISSINEWA SHALE-LISTON
CREEK LIMESTONE CONTACT IN NORTHEASTERN INDIANA
I. INTRODUCTION
ThE~
Wabash Formation, with its encompassed Mississinewa
Shale and Liston Creek Limestone Members, is a Silurian interreef deposit of late Niagaran age (Shaver et. al., 1971)
(figure 1). In northeastern Indiana the contact between
these two members is exposed at several quarries, road, and
stream cuts. Existing contemporaneously with the deposition
of the Wabash Formation were numerous pinnacle reefs in addition to two major reef complexes along the edges of the Michigan and Illinois basins (Shaver, 1978). These Silurian reefs
of the Midwest have been, over the last few years, the targets of petroleum exploration, and are prized as sources of
crushed stone and chemical-grade carbonates. In southwestern
Indiana, petroleum has been extracted from the overlying
strata which are usually domed due to differential compaction
of subsequently deposited layers. In some areas, such as in
Michigan and Illinois, but not in Indiana as yet, petroleum
has been produced directly from the reef bodies (Becker and
Keller, 1976).
A.Purpose of Study
The objective of this research is to determine how the
detrital component of the Wabash Formation varies in the
2
DROSTE AND SHAVE R 1976
PINSAK AND SHAVER, 1964
illW~
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~
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.Liston
::.:.:~'.~r- and <l:
~
fr
:r
en
~
~
Creek
Ls. Mbr.
.:":Cfl:: Kokomo
~:w:'( Ls. Mbrs.
:'.- ~~
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M.ississlnewa «flL ... ~
Sh. Mbr. t::·:·::~
~
9.<t":4 ~
t.lL .~~
1-------'-----7
~.::
(:··~
LOUISVILL E \~'.~.)
LlMESTONE~:.:-:·:.1
<•• ::.!<
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<l:
(j)
<l:
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<l:
0.......
and Kokomo
Ls. Mbrs.
(f)
"r..
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:::>
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0
_
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a:
u..
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Mississinewa
Shale Member
1982
~
f2 1---------""------.,
(f)
DROSTE AND SHAVER
11111111111 I II
~enneth
Liston
Creek
Ls. Mbr.
a: :r
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:.~ ::0
<-.:. w .~
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white
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Kenneth
Liston r- ond Creek
Kokomo
Ls. Mbr. Ls. Mbrs.
Mis sis sin e wa
Shale Member
Z-.J
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..J
c::::
c::
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~
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CJ)
Louisville
equivalent
~ ~~--------1
e
Waldron
e~quivo~~
Lim be r los t
Dolomite Member
dolomite
SALAMONIE DOLOMITE
SALAMONIE DOLOMITE
SALAMONIE DOLOMITE
Figure 1. - Chart showing the evolution of nomenclature
of Middle (Niagaran) and Upper (Cayugan) Silurian rocks
(from Droste and Shaver, 1982, Fig. 2).
-
1
en
WALDRON FM.
CJ)
~
........ ~
brownn4'j:':":: ':'.:~.L.ld.Llo'-'-loLlm.lJi-'-teLl.lJ...LL.L~~---=-:-,-:LL':-=I:=:'M=:-S'" E R LOS T )
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3
vicinity of the Mississinewa-Liston Creek contact. As early
as 1927, in the work of Cumings and Shrock (1927), it was
noted that there was a decrease in the silica content of the
Mississinewa Member in a traverse from Yorktown to Kokomo
(30.28 percent at Yorktown to 15.90 at Kokomo).
Owens (1981) further developed this issue of using terrigenous clastics as a research tool in his work on the Mississinewa Member. Owens determined two source areas for the
supply of detritus to the Mississinewa shale. Figure 2, a
map displaying the regional distribution of insoluble residues in the Mississinewa Member, indicates these two source
areas. One of these, southeast of the Wabash Formation outcrop area, was a clay-rich source. This source was supplied
via ocean currents carrying materials derived possibly from
the Appalachians, or exposed Ordovician sediments in the
Cincinnati area. Silt and clay from this source settled out
of suspension in high concentrations in the southeast of
Owens' study area (extreme southeastern Madison and Delaware
counties) (figures 3 and 4). Finer silt and clay remained in
suspension and was finally deposited further northwest in
substantially lower concentrations.
The second of Owens' sources was a
sil~rich
source
from the northwest (figures 3 and 4). Figure 5, a map illustrating the regional distribution of silt-clay ratios in the
Mississinewa Member of the Wabash Formation, shows the greater
potency of the northwestern source as a source of silt.
Owens believed this source was of aeolian origin, blown into
4
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o
Scale
I
5
mil ..
1
10
Figure 2. - Map displaying the regional distribution of
insoluble residues in the Mississinewa Member of the 1rJabash
Formation. Notice areas of higher concentration at the
northwest and southeast corners. Black dots represent localities where the entire stratigraphic sequence was sampled.
Small tr~angles indicate sites where a single sample representative of the entire exposure was collected. Large black
symbols indicate reef-proximal localities. Contour interval
e~uals 10 percent (from Owens, 19~1, Fig. 9).
~
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L._.~·=~L.,
Seal.
Contour Interval = 10%
I
o
-
A
1
miles 10
Figure J. - Regional distribution of silt in the Mississinewa Member of the Wabash Formation. Notice increased silt
in northwest and southeast corners. Values represent silt
content as a percentage of total lithologic composition.
Black dots represent localities where the entire stratigraphic sequence was sampled. Small triangles indicate sites where
a singlE! sample representative of the entire exposure was
collected (from Owens, 1981, Fig. 10).
6
N
IMi~ I
I
Wab:ab
~
I - 10
I
6 .
10
L
r--
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8.
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1
r :j
~10 t4 , -
I
AJ--~
• I
SCALE
o
20
r-
L;;;;
J
1 inch
= 20
miles
Figure 4. - Map illustrating the regional distribution
of clay as a percentage of total lithologic composition.
Notice areas of higher concentration of clay at the northwest and southeast corners. Contour interval equals 5
percent (from Owens, 1981, Fig. 12).
- --
--
.- . .
_"
~~I
.
,.,
.1
.
1
Scale
CONTOUR INTERVAL· 15.0 %
I
o
I
5
..,11 ..
1
10
Figure 5. - Map illustrating the regional distribution of
silt-clay ratios in the Mississinewa Member of the Wabash
Formation. Black dots represent localities where the entire
stratigraphic sequence was sampled. Small triangles indicate
sites where a single sample representative of the entire
exposure was collected (from Owens, 1981, Fig. 11).
-
8
the marine waters from arid lands west of the Michigan basin.
The amount of detritus, from this source, decreased to the
southeast.
B. Significance
Should it be possible to determine some sort of pattern
in the silt and clay components of the Wabash Formation at
the Mississinewa-Liston Creek contact, it-might Bhed light
on the events that caused the abrupt lithic change at this
contact. Paleocurrents, paleowinds, and paleoclimatic events
might be deduced if this pattern could be applied over a
large area, such as northeastern Indiana.
C. Selection of Field Localities
Silurian rocks in Indiana crop out in a broad belt in
northeast Indiana, extending southward in some areas (figure 6). This general region became the basis for this study.
In. order to test Owens' data, and examine the upper
contact relationship of the Mississinewa with the overlying
Liston Creek, four sample areas were selected. Two of these
were in the vicinity of Wabash, at the northern end of the
Silurian outcrop area of Indiana. Two other localities were
selected at the southern edge of the Silurian outcrop belt
(figure 7). The exact locations of these localities are
as follows:
1. Wabash: Deep road cut on state road 13 on the south
edge of Wabash, Indiana, North Reserve 55, T27N,
R6E
2. Shanty Falls: 3 miles west of Wabash, Indiana, southern bank of the Wabash River, north Reserve 55, T27N,
R6E
9
.-
I
Fig~re
Generali
Indlana 6.and- parts
0 zed.g~ologic map of
f
(from Pinsak and Shaver
adJolning
states
, 1964 , Flg.
.
1).
10
-
N
SCALE
o
20
~ b1Q me:J
1
1 inch
~
20 miles
Marion
Figure 7. - Map of study region showing sampling
localities. site 1 - Wabash, site 2 - Shanty Falls,
site 3 - Noblesville, site 4 - McCordsville Study
region equals approximatelY 470 square miles.
11
3. Stony CreeK Stone Co., Inc., R. R. 4, Box 133A
Noblesville, IN 46060, 4 miles E of Noblesville
on S. R. 38, Riverwood Quad., SEiNEi sec. 3 T18N,
R5E
4. Irving Materials, Inc., R. R. 1, Fortville, IN
46140, 3.5 miles N of McCordsville on C. R. 600 W.,
McCordsville Quad., NEiswi sec. 2, T17N, R5E
It was intended that the selection of these four field
localities would permit the discovery of any possible regional trend. By selecting two sites that were reasonably close
to each other, a limited check could be made on the accuracy
of the subsequent laboratory procedures. The choice of
localities was rather limited due to the fact that the Mississinewa-Liston Creek contact is exposed in so few places
at the surface. A more complete study would need access to
drill cores.
The southern two sites both are located in
quarries~
The northern two sites lie in a region long noted for its
Silurian age deposits (Gorby, 1886; Elrod and Benedict,
1891).
10
-
N
fI
SCALE
o
I
1 inch
20
tm"mw:J
~
20 miles
Marlon
Figure 7. - Map of study region showing sampling
localities. site 1 - Wabash, site 2 - Shanty Falls,
site 3 - Noblesville, site 4 - McCordsville Study
region equals approximately 470 square miles.
11
-
3. Stony Creek Stone Co., Inc., R. R. 4, Box 133A
Noblesville, IN 46060, 4 miles E of Noblesville
on S. R. 38, Riverwood Quad., SEiNEi sec. 3 T18N,
R5E
4. Irving Materials, Inc., R. R. 1, Fortville, IN
46140, 3.5 miles N of McCordsville on C. R. 600 W.,
McCordsville Quad., NEiswi sec. 2, T17N, R5E
It was intended that the selection of these four field
localities would permit the discovery of any possible regional trend. By selecting two sites that were reasonably close
to each other, a limited check could be made on the accuracy
of the subsequent laboratory procedures. The choice of
localiti.es was rather limited due to the fact that the Mississinewa-Liston Creek contact is exposed in so few places
at the surface. A more complete study would need access to
drill cores.
The southern two sites both are located in quarries9
The northern two sites lie in a region long noted for its
Silurian age deposits (Gorby, 1886; Elrod and Benedict,
1891 ) .
II. GEOLOGIC SETTING
A. Structural Setting
Structurally, Indiana is dominated by two basins,
separated by a system of arches. The axis of the principal
arch, the Cincinnati Arch, trends northward along the Indiana-Ohio State Line, then branches, with one branch that
trends northwestward, the other northeastward. In the vicinity of Cass County, the northwestern branch joins the Kankakee Arch, a southeastern extension of the Wisconsin Dome
(Becker,
1974). To the northeast of this feature is the
Michigan Basin, and to the southwest the Illinois Basin (figure
8). Some earlier authors such as Pinsak and Shaver (1964)
termed the entire Cincinnati-Kankakee Arch system simply the
Cincinnati Arch.
During the Silurian, the area between the Michigan
and Illinois Basins was so broad that Shaver
(1978) has
termed· this area the Wabash Platform (figure
9). This plat-
form became the site of nilllerous pinnacle reefs. Along the
margins of the platform, barrier reef complexes developed.
The complex on the edge of the Michigan Basin has been termed
the Ft. Wayne Bank, and the one along the edge of the Illinois Basin, the Terre Haute Bank. These banks and individual
reefs have been the topic of numerous articles such as those
1.3
,----------
S'iiUIo.--'
LAX! MICHIGAN
I
I
,
I
.J
Wl.
I
Of lAtl
I
I
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AUfN
HUNTINGTON
. . . : ......-;:j
WEUl
ADAiiiNi
GRANT
IlACKFORD
JAY
WOOOlPH
WAYNE
2S
I
I
I
I
I
o
or
2S Miles
2S Km
Figure 8. - Map of Indiana showing county names and
major structural features (from Carpenter, Dawson,
and Keller, 1975, Fig. 1).
?•
o
200 Miles
- - L I - r l_~--1-.1---,J
o
300 Km
t-I
+
Figure 9. Map of the Great Lakes area showing paleogeography and locations of some but not all known discrete
-reefs (dots and stars), carbonate banks or barrier reefs
(stipples), and gross structural-sedimentational features,
all composited for Silurian time. Individual reefs are not
shown in bank areas; arrows represent reported forereefto-backreef directions for given reefs (from Shaver, 1978,
Fig. 1).
I
-
15
by Carrozzi and Zadnik (1959), Textoris and Carrozzi (1964),
and Droste and Shaver (1980) to name but a few.
B. Stratigraphy of the Wabash Formation
The stratigraphy of the Wabash Formation and its adjacent formations have undergone a gradual evolution of nomenclature. The Mississinewa and Liston Creek Members were
originally described respectively as an irregularly fractured
"cement rock" of approximately 135 feet overlain by 60 feet
of cherty limestone or "quarry rock" (Elrod and Benedict,
1891) .
The current nomenclature for the Niagaran and Lower
Cayugan Series began to take form through the work of Pinsak
and Shaver (1964). They named the stratigraphic sequence for
Indiana (oldest to youngest) as the Salamonie Dolomite,
Waldron Formation, Louisville Limestone, and Wabash Formation.
The Salamonie Dolomite is named from the exposures of
dolomite in the headwaters area of the Salamonie River in
the vicinity of Portland, Jay County, in east-central
Indiana. It is characteristically a ligh-colored mediumgrained fossil-fragmental porous dolomite. The Waldron
Formation in northern Indiana consists of distinctive
mottled dark-gray and tan fine-grained to sublithographic
argillaceous limestone or dolomitic limestone. The
Louisville LImestone characteristically is tan and gray
fine-to medium-grained thick-to medium-bedded fossilfragmental limestone and dolomitic limestone. The Wabash
Formation has two major subdivisions, the Mississinewa
Shale Member and the Liston Creek Limestone Member.
The Mississinewa Member generally is composed of gray
fine-grained argillaceous silty dolomite and dolomitic
siltstone and minor amounts of pyrite. The Liston Creek
Member consists of a light-gray and tan fine-to mediurngrained fossil-fragmental cherty limestone and dolomitic
limestone (Pinsak and Shaver, 1964, pp. 24-39).
This nomenclature has been modified twice since its
inception by Droste and Shaver (1976) who proposed the name
16
Limberlost Dolomite be used for the upper portion of the
Salamonie Dolomite. This unit was formerly termed the brown
upper part of the Salamonie Dolomite, but was renamed the
Limberlost Dolomite due to its differing lithology. In addition,
the Limberlost Dolomite represents the onset of restrictive Salina influences within the Michigan Basin that
transgressed in time onto the Wabash Platform as far
south as Indianapolis (Droste and Shaver, 1976, p. 1).
Droste and Shaver (1982) further proposed the combination of the Limberlost, Waldron, and Louisville Limestone
Formations under the new name Pleasant Mills Formation. This
. proposed regrouping is designed to reflect, considering the
Great Lakes area as a whole, a complete facies relationship
that existed between the evaporites of the Michigan Basin
and the interbasin rocks of the Wabash Platform. The Pleasant
Mills and Wabash Formations are subsequently placed in the
Salina Group, a name previously applied only to the evaporites of the Michigan Basin. Figure 1 shows this gradual evolution of nomenclature.
In keeping with this new nomenclature, Droste and Shaver
'(1982) have extended the Wabash Formation northward into the
Michigan Basin
to include all rocks in the upper part of the Salina
Group, that is, those Salina rocks lying above the
Pleasant Mills Formation (Droste and Shaver, 1982 p.
21) .
Southwestward, the Wabash Formation is roughly correlated to
-
I
the upper Moccasin Springs Formation and lower Bailey Limestone of the Illinois Basin. Figure 10 shows these correlations.
17
-----
'Z
ct
(.)t/'I
uJ
a:
wa:
:i: W
ctt/'l
SOUTH-CENTRAL
INDIANA
CENTRAL AND
SOUTHERN
MICHIGAN
NORTHERN INDIANA
o
X.J:l
UJ
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u c
11.
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UJ
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ID
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o
III
...
(II
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E
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Liston
Creek
Ls. Mbr.
Kenneth
and
Kokomo
Ls. Mbrs.
LL
w
uJ
Q.
~
.
u
(/)
UJ
u
....... .. ~ ....o .
Mississinewa
o
UJ
UJ
.J
.J
0
ro----------
w
z
o
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Vl
~
Vl
~
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OIl
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o
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cr
<[
w
z
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=>
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Z
Limber!ost
Dolomite Member
o
c::x:
I
<t
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~
.J:l
u
~
:i!
UJ
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~
.J
~
SALAMONIE
DOLOMITE
<[
~
C>
0
~
~
o-
•
~
<[
'U
0
o
C1'
OIl
o
-
z
....
......
.J
cr z :'!!
Z
W
11.
.J
3:
U
0
o
Figure 10. - Chart showing the evolution of nomenclature
of Middle (Niagaran) and Upper (Cayugan) Silurian rocks
(from Droste and Shaver, 1982, Fig. 2).
-
0
0<[0
U
0
<[cr
~
0
0
.••••.•.• ::!: ...............................................................................................
.
z
0
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c::x:
.J
UJ
o
a..
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equivalent
W
W. FM.
o
z
Louisville
>
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0
>
Z
N
I
Z
(/)
•..0
::!:
0
Z
(.)
<[
cr
c::x:
0::
0
0
(/)
--- Shale Member ---
11.
-
W
-1
.......................................0: ................... .
<[
z
(J)
W
0...
z
i<.!)
(/)
<t
WESTERN 0 a:
w
a: (J)
OHIO
~
BASS IS. GR.
Z
(!)
NORTH-
uJ
UJ
<t
)-
AREA OF THIS REPORT,
AND
Z
z
=>
Z
SOUTHWESTERN
OZ
oc::x:
zc::x:O::
.JW
-.J~
.!
18 "
C. Paleogeographic Setting
Du~ing
the Silurian, paleogeographic evidence seems to
indicate that the Midwest region o£ the United States was
located somewhat south o£ the equator at approximately 1020 0 S latitude (see Appendix E). This was a period o£"relatively rapid continental drift, as the same region was previously located at approximately 20-30
0
the Ordovician, and subsequently at 8-18
the Devonian, and 0-10
0
S latitude during
0
S latitude during
N latitude during the Carboni£erous
(Habicht, 1979).
D. Depositional Model
Prior to Owens'
(1981) research, the depositional model
for the Silurian of Indiana was one in which terrigenous
clastic;s were deposited from the southeast in "surges"
(Shaver et. al., 1971). Shaver (1974) £urther stated that
both the rocks and fossils in the Liston Creek interreef facies suggest an environment of higher energy
and shallower water than that of the Mississinewa
(Shaver, 1974, p. 946).
Several researchers have tried to use the forereef-tobackreef direction of Silurian reefs to determine the current and wind directions during their deposition. Lowenstam
(1950) used the areal distribution o£ reef outwash and bypassed terrigenous sediments at several reefs in the Niagaran archipelago (Terre Haute Bank) area of Illinois to deduce a prevailing southerly wind. Crowley (1973) in similiar
research on the Middle Silurian patch reefs of the Gasport
I
.-
-
19
Member (Lockport Formation) in New York came to the conclusion that wind-generated currents from the northwest were
responsible for the north-to-south forereef-to-backreef relationships that he found.
--
I
III. FIELD METHODS AND LABORATORY PROCEDURES
A. Field Methods and Sampling
The Mississinewa-Liston Creek contact at the four
sample sites was deduced on the basis of differences in
lithology and weathering profile. Once the contact was identified, samples were taken above and below the contact. Above
the contact, samples were taken at six inch intervals beginning at the top of the contact itself. This was continued
up section to three feet above the contact. Below the contact,
samples were taken at foot intervals beginning at the base
of the contact. This was continued down to three feet below
the contact. A total of eleven samples was taken at each
of the sampling sites.
For each sample collected, several pieces of rock were
taken for a total of approximately 500 grams. Great care was
taken to collect samples that were in place, not talus from
higher. layers, as this could badly confuse results.
B. Laboratory Procedures
Laboratory analysis was initiated with two goals in
mind. The first of these was to determine the percentage of
detritus in each sample. The second goal was to acquire a
grain-size distribution for each sample by the pipette method
of Folk (1968).
21
1. Insoluble Residue Analysis
Insoluble resfdue analyses were conducted to determine the vertical distribution of insoluble detritus above
and below the contact at each site. The method used was similiar to that used by Owens (1981) with some personal modifications.
The detrital analysis of each sample began with weighing out approximately 100 grams of sample. This sample was
then crushed with a rock hammer to marble-sized chips. These
were
sU~Jmerged
in a 25% HCI solution, with additional acid
added when needed to completely dissolve the sample. Once
the carbonate was dissolved, the sample was filtered through
filter paper to catch the detritus. The filtered sample was
then "flushed" several times with distilled water to cleanse
it of any unreacted HCI that might cause flocculation in
the pipette process. The detritus was dried and weighed, and
its percentage as part of the original sample weight was
calculated (figure 11).
2. Pipette Analysis
Ten to fifteen gram samples of the insoluble residue
derived from the dissolution process were next run through
a 4~ wet sieve in order that the sand and mud fractions
might
bl~
split. It was found that almost the entire amount
of each sample was less than
4%
(silt and clay). What was
not, was dried and weighed to determine the mass of the sand
fraction.
-
Insoluble residues of the mud size range can be analyzed
by the procedures outlined by Folk (1968). The core of this
)
Calcite Digestion
Crush
Sample
> Add/~ Recharge
25%
HCL
> Spent
Hel
Dolomite Digestion
I
Recharge
) Spent
HCl
(warm)
>
Filter,
Wash
With
Distilled
Water,
Dry
Calculate
') Percent
Detrital
Figure 11 - Insoluble Residue Procedural Flow
Chart (modified from Owens, 1981, Fig. 5)
1\)
1\)
2J
process is an equation derived from Stokes Law:
T
=
D
1500 x A x d
where:
2
D is equal to the depth of pipette
submersion
1500 is a constant
A is a constant dependent upon temperature at the time of the experiment and
particle density (assumed to be that of
quartz)
d is the diameter (mm) of the various
particle sizes the experimenter wishes
to retrieve
T is settling time (in minutes) required
for the particle to settle a given distance
beneath the surface
The methodology of the procedure was to take each mud
fraction that passed through the wet sieve and place it in
a standard kitchen blender with additional dispersant solution. This solution had dissolved in it a calgon dispersing
agent .(7.4g/liter). The mud sample was then mixed for several
minutes and placed in a one liter graduated cylinder.
The graduated cylinder was next allowed to set out overnight. The purpose of this was twofold. First, to see if the
dispersant was of sufficient concentration, and second, so
that the temperature of the water in the cylinder could
equalize with the room temperature. The following morning,
the cylinders (usually in groups of three) were placed in an
insulated ice chest. Alequots of 25 milliliters were drawn-off
24
-
c
by pipette at the required times calculated by the equation
given on the previous page, and placed in pre-weighed beakers.
After each withdrawal, the ice chest was sealed in order that
the initial temperature (the one the values for T were based
on) could be maintained. The beaker was next dried in 'an oven
and weighed. The mass of the dried sample was miltiplied by
40 (because the 25 milliliter alequot was 1/40th of the whole
liter) to find the mass of particles still in suspension.
The difference in mass between two successive alequots corresponds to an entire
%size
which has settled out of suspen-
sion. (figure 12). A sample data sheet is found in Appendix A.
c.
Procedure Reliability
Two preparations of each rock sample were processed.
The data from these two trials were then compared for discrepancies. This means that a total of 88 trials were run
through the above-discribed procedure.
--
)
)
Weigh
san1fSize Fraction
10-15' Gram
Sample
)
Add Dispersent
Solution and
Blend
) Wash through .
Wet Sieve
> Place
in
Graduated
Cylinders
~
--~)
Check
Dispersion
Effectiveness.
Stir
and
Initiate
Timing
~
Calculate Cumulative
Percentages
~
Plot DistributiQns
on Log-Probablllty
Paper
Figure 12. - Pipette Analysis Procedural
Flow Chart (modified from Owens, 1981,
Fig. 6)
l\)
V\
IV. INTERPRETATION
The data generated from laboratory analysis was used to
construet a series of graphs. In the plotting of these graphs
(see Appendixes B-D), along the ordinate was placed the relative position of the sample above or below the MississinewaListon Creek contact. Each foot interval over which the samples were taken was given a constant interval on the graph.
This interval was also used to separate the sample taken below
the contact from the one taken above the contact for an emphasis of the contact itself.
All four sequences of Mississinewa-Liston Creek samples
show some decrease in detrital content as the contact is
approached. The site that shows the least decrease in percent detritus is the McCordsville site, which is the site
nearest the clay-rich source area southeast of the study area.
The other sites showed a much greater decrease in detritus
at the contact, especially the northern two sites near Wabash
(see Appendix B).
The silt/clay curves for the sites show a less pronounced pattern (see Appendix B). At three of the sites
(Wabash, Shanty Falls, and Noblesville) there is a general
decrease in the ratio up section. At the McCordsville site,
the ratio actually increases somewhat above the contact.
27
When the silt "and the clay content for the four sites
are plotted against the carbonate content (that is assuming
that the parameter of carbonate production is somewhat constant) an interesting pattern emerges (see Appendixes C and
D). The northern two sites show almost no silt
a~ter
Missis-
sinewa depostion stops. The southern two sites, Noblesville
and McCordsville, show a somewhat higher level of silt versus
carbonate, but these higher levels characteristically appear
in surges at different distances above the MississinewaListon Creek contact. The clay versus carbonate of these two
southern sites also show surges· in clay content. These increases in clay at Noblesville and McCordsville occur in the
same samples as do the surges in silt, and again, the McCordsville site shows somewhat higher levels than that of the
Noblesville site. The clay versus carbonate curves of the
northern two sites, Wabash and Shanty Falls, show generally
uniformly lew levels after the end of Mississinewa deposition.
A further analysis of the data was made by constructing,
for each sample, a grain-size distribution curve on probability paper. A comperison of these curves was made to that
of a cumulative grain-size distribution of a loess deposit,
the type of curve match on which Owens (1981) based his
theory of aeolian transport (figure 13). The curves of those
samples below the contact closely matched the loess deposit
curve, those above the contact did not.
-
I
It is this author's interpretation that after the end
of Mississinewa deposition, the supply of northern silt
28
CUM
%
99
4
5
9i
7
SIZE
8
9
10
Figure 1J. - Comparison of cumulative grain-size distributions of a loess deposit, Nemaha Gouny, Kansaa
(after Swineford and Frye, 1945) to those of samples
below and above the Mississinewa-Liston Greek contact.
•
•
cumulative grain-size distribution of a loess deposi
(8
E1
[!j
typical cumulative grain-size distribution below
Mississinewa-Liston Creek contact
e
9
9
typical cumulative grain-size distribution above
Mississinewa-Liston Creek contact
II'
C
stopped. This is suggusted by both the detritus and cumulative grain-size distribution curves. What is left of the
terrigenous clastic supply is being supplied in surges from
the southeastern clay-rich source only. The bulk of this
material settles out. of suspension long before it reaches
the northern two sites of Wabash and Shanty Falls. In fact,
a great portion of silt-sized particles settled out between the sites of McCordsville and Noblesville.
Why did aeolian transport of the silt-rich source to
the northwest cease? A simple solution to this would be
vegetation growth in the source area slowing the rate of erosion. Such vegetative cover could have been provided by
lichens, of which Blatt, Middleton, and Murray (1980) stated,
it seems
chens to
rence as
Silurian
p. 251).
reasonable to suppose that the ability of ligrow on bare rock is related to their occurone of the earliest colonizers of land in the
Period (Blatt, Middleton, and Murray, 1980,
A more satisfactory solution would be to model the wind
patterns of the Silurian after existing wind patterns of today.
If we accept a paleogeographic setting of 10-20 0 S latitude
for the Midwest of the United States, this would place the
study area in the monsoonal region (figure 14). The monsoonal
region refers to a region where
surface winds flow persistently from one quarter in the
S~lmer and just as persistently from a different quarter
in the winter (Ramage, 1971, p. 1).
Ramage (1971) further states that,
monsoons blow in response to the seasonal change that occurs in the difference in pressure-----resulting from the
difference in temperature----between land and sea.
Where continents border oceans, large temperature
30
Figure 14. - Illustration of monsoonal regions. Hatched
areas are monsoonal, heavy line marks northern limit of
the region within the Northern Hemisphere with low frequencies of surface cyclone-anticyclone alternations in
9ummer and winter. Re<;:tangle encloses the monsoon region.
\from Ramage, 1971, Flg. 1.2)
-
I
Figure 15. - Silurian paleogeography of the Great Lakes
area A, Late Wenlockian to early Ludlovian (Niagaran)
time. B, Pridolian (Cayugan)time (from Shaver, 1978,
"Fig. 23)
31 .
differences and hence large differences in pressure
might be expected. However, the shapes of continents
and their topographies, as well as variations in seasurface temperatures, all interact to produce considerable regional and temporal variability in the monsoons.(Ramage, 1971, p.8) .
. During the summers in monsoonal regions, land masses
heat-up more rapidly than do the nearby bodies of water, and
subseqUE:mtly become areas of low pressure; such a region is
termed a cyclone. The wind direction of a cyclone is counterclockwise in the Northern Hemisphere, clockwise in the Southern Hemisphere. During the winter, the same land masses cooloff more rapidly and become areas of high pressure; such a
region is termed an anticyclone. The wind direction of an
anticyclone is clockwise in the Northern Hemisphere, counterclockwise in the Southern Hemisphere (Ramage, 1971).
Desert regions are excellent examples of regions that
seasonally change temperature. Just such a region is theorized
by Shaver (1978) to have existed to .the northwest of the study
area (figure 15). This desert region, along with a paleogeographic setting of 10-20
0
S latitude would suggest a
modeling of the Silurian in this area after the present Eastern Africa and Western Indian Ocean region.
The African continent spans the equator and so in January radiational cooling results in high pressures over
the Sahara and Arabia; radiational heating results in
low pressure over the Kalahari Desert. The consequent
north-south pressure gradient sets up a flow of air from
north to south across the equator. The most intense heat
lows overlie deserts and occupy the same latitude over
the oceans. In contrast to January, radiational cooling
res~lts in high pressure over the Kalahari Desert, and
radiational heating, in low pressure over the Sahara.
32
The south-north pressure gradient sets up a southerly
flow across the equator, eventually merging with the
southeast trades over the southern Indian Ocean and
with the southwest monsoon north of the equator. The
upwelling effect, mentioned above contributes to the
southerly monsoon being stronger than the northerly
monsoon of January (Ramage, 1971, pp 11-16).
This seasonal variation in wind, besides being an excellent model, might explain the differences in wind direction cited by Lowenstam (1950) and Crowley (1973).
At
the close of Mississinewa deposition this seasonal variation in wind must have been disrupted by continental drift
or some other mechanism.
The southeast current needed to supply detritus from
the clay-rich source to the southeast of the study area would
also exist in the Eastern Africa and Western Indian Ocean
region. Figure 16 shows a clockwise current existing in the
Indian Ocean today that would fit nicely.
JJ
-
---------
-~--
---------.....,r
Figure 16. - Present world distribution of arid zones and
ocean c~rrents. solid arrows-cold currents, dashed arrowswarm currents, dotted areas-deserts, diagonal lined areassteppes (from Habicht, 1979, Fig. J).
<
v.
CONCLUSIONS
The Mississinewa-Liston Creek contact represents a
change in the depositional environment in the northeastern
Indiana region. It represents the transition of an area
being supplied by two terrigenous clastic sources, to an
area being supplied by onJ.y one source. The events that
triggered this change are only conjecture upon the part of
this author. Possible explainations for this change are
changes in the wind pattern caused by continental drift,
or vegetation growth in a terrestrial source area that existed
to the northwest.
-.
VI. REF'ERENCES CITED
Becker, Leroy E. 1974, Silurian and Devonian Rocks in Indiana
Southwest of the Cincinnsti Arch: Indiana Geol .. Surv.
Bull. v. 50, pp. 83.
Becker, Leroy E., and Keller, Stanley,J. 1976, Silurian Reefs
in Southwestern Indiana and Their Relation to Petroleum
ACGumulation: Indiana Geol. Surv. Occasional Paper 19,
p. 11.
Blatt, Harvey, Middleton, Gerard, and Murray, Raymond. 1980,
Origin of Sedimentary Rocks: Prentice-Hall Inc., Englewood Cliffs. New Jersey. p. 251.
Carpenter, G. L., Dawson. T. A .• and Keller, S. J. 1975, Petroleum Industry in Indiana: Indiana Geol. Surv. Bull.
v. 42, p. 57.
Carrozzi, A. V. and Zadnik, V.E. 1959. Microfacies of Wabash,
Indiana: Jour. of Sed. Pet .• V. 29, pp. 164-171.
Crowley. D. J. 1973. Middle Silurian Patch Reefs in Gasport
Member (Lockport Formation), New York: Am. Assoc. Petroleum Geol. Bull. v. 57, pp. 283-300.
Cummings, E. R., and Shrock, R. R. 1928, Niagaran Coral Reefs
of Indiana and Adjacent States and Their Stratigraphic
Relations: Geol. Soc. Amer. Bull. v. 39. pp. 579-620.
Droste, John B., and Shaver, Robert H. 1976, The Limberlost
Dolomite of Indiana; a Key to the Great Silurian Facies
in the Southern Great Lakes Area: Indiana Geol. Surv.
Occasional Paper 15. p. 21.
____-=__ . 1980, Recognition of Buried Silurian Reefs in
Southwestern Indiana; Application to the Terre Haute
Bank: Jour. of Geol. V. 88, pp. 567-587.
______~. 1982, The Salina Group (Middle and Upper Silurian)
of Indiana: Indiana Geol. Surv. Special Report 24, p. 41.
Elrod, M. N .• and Benedict, A. C. 1891, Geology of Wabash
County: Indiana Dept. of Geology and Nat. Resources, Ann
Report 17, pp. 192-272.
-
36
Folk, Robert L. 1968, Petrology of Sedimentary Rocks: The
University of Texas, pp.170.
Gorby, S. S. 1886, The Wabash Arch: Indiana Dept. of Geology
and Nat. Resources, Ann. Report 15, pp. 228-242.
Habicht, J.K. A. 1979, Paleoclimate, Paleomagnetism, and
Co~tinental Drift: Am. Assoc. Petroleum Geol. Studies
in Geology no. 9, pp. 1-30.
Lowenstam, H. A. 1950, Niagaran Reefs of the Great Lakes
Area: Jour. Geol. v. 58, pp. 430-487.
Owens, Robert N. 1981, Petrologic Analysis of the Mississinewa
Member of the Wabash Formation and the Effect of Reef
Proximity on interrreef Sedimentation: unpub. M. S. thesis,
Ball State Univ., Muncie, Indiana, pp. 1-83.
Pinsak, A. P., and Shaver, R. H. 1964, The Silurian Formations
of Northern Indiana: Indiana Geol. Surv. Bull v. 32,
pp. 1-87.
Ramage, C. S. 1971, Monsoon Meteorology: Academic Press, New
York and London, pp.296.
Shaver, et al. 1971, Silurian and Middle Devonian Stratigraphy
of the Michigan Basin; a View from the Southwest Flank,
in J. L. Forsyth, ed., Geology of the Lake Erie Islands
and Adjacent Shbres: Michigan Basin Geol. Soc., pp. 3759.
Shaver, R. H. 1974, The Silurian Reefs of Northern Indiana;
Reef and Interreef Macrofaunas: Am. Assoc. Pet. Geol.
Bull. v. 58, pp. 934-956.
, and others. 1978, The Search for a Silurian Reef
Model Great Lakes Area: Indiana Geol. Surv. Special
Report 15, pp. 1-36.
Swineford, A., and Frye, J. E. 1945, Petrographic Comparison
of Some Loess Samples from Western Europe with Kansas
Loess: Jour. of Sed. Pet. v. 25, pp. 3-23.
Textoris, D. A., and Carrozzi, A. V. 1964, Petrography and
Evolution of Niagaran (Silurian) Reefs, Indiana: Am.
Assoc. Petroleum Geol. Bull. v. 48, pp. 397-426.
!----
Appendix A
Pipette Analysis Data Form
I
-
)
PIPETTE ANALYSIS
SAMPLE NO.
REMARKS _______________________________
TEMPERATURE
rJ
,4';_""",
\..liOlU.
74
depth(cm)
1
FORM
LOCATION _________________________________________________________
EXPERIMENTER'S NAME
P
DA~A
CONCENTRATION OF DISPERSENT _____________
time
beaker no.
weight obtained by wet sieving-
sample and
beaker
______
sample wt.
beaker
wt.
X40
dIspers
cum.~.
__ ilQQSl
[S+F)
{Sl
Z4
{f)
~
(p)
~6
(rl
S2
_ _ 1._p.<-.1_ _
Z8
{p)
~
- - ~(P,-,-)--.
< 10
(pl
100(S+(F-P) )
S+F
\..oJ
co
Appendix B
Stratigraphic Distribution of Total Detritus
(percent insoluble) and Silt/Clay Ratio
I----
MG coP-OS \.r~1-LE ) l=rlDTN'v'A
-r('io..l ±:l.:2
Tf'io...l ±l:.1
I
3~1"
(
Ao:-,;e,
r
tI -
40
'2.~
AtN<...
~
t R\.-t
~
Ab;1J~
<...NI)~(
BJow
~'fltac;
©;.
,~
'\
2F6:t
&/ow
3tcd
&Io<.u
b_'ic
;Ut
3 ..'10
I.{c/"
Fk::tcen+-
:;";"'1,,
(:<::i~
?I)}.
De+1' itt. i
j'
(
Tria. I H(
3~~
2~
f'ki,;4
1f::tx1-
nb:i.~
!!141-. ~
~/~
G..:.i\
..
fulc:t..
<. urkd
i foot
8..~ON
~-
\
2fe.z\
&!ie.1i
3~">t:i~IOVJ
~--I-~!IIII
0..0
II)
\;"~:.",,,r<d"
o.~
II,,, C.nti""·,,.
08
j.1.
L::>
5/1+;e.Iu.y
,S
2 .. /
I
0 .. 6
0,10
I
08
1~7_
I
l-f
;.5 I'~
S;/i/C/QY
:2.!
Noblesv i I Je~ J j : n cl. i'ClnCL
I {' i t.l I H. (
Tria. I
41
..Y 2.
3~t
Ab. :l:
(:-.
2#ee1"
A~'~
I~
Abc"f!:,
Abc~'e
c".,,,,",-
c
.:?
1F=c.:r
~
Bt:,",-,
V
0
"2.~t
-.J
&If,,,,,
3n
lX.jc~
2i:)'(.,
.'11;:11:
'tC1"
~c!..
f
be;:.
-:;>'::;'1,
fkrcen+ De.t,'1/ -k I
I{:::/<.
I
.:Xl.
~('ce/')-t-
.1 <
e-C.'Ii
~+I'i+c\.l
Tried t±/
'3~~T
Ilb..; v e
2Nd'
Abo.;lZ.
i ~a:J-
i~
Ab;.y(L
Abtl-<!o
C
<>
~
0
0
--.I
,
. ,,.-.,
\1
c:...:..lf1:4'
tkak\;.l
Gu\fu.c:t
I~Cl..i-
Beio.u
'2~t
&ow
3Fe.i::
8elc ......
o.~
t. ?>
0.'1
1.'1
1.:1
5,' It/C/Q."j
I
7cl..
1.C6
,
~CL\15
S ha..nty
Tfio...)
ttl
Tf'icJ
.3~
I. -.:.-.:!
(-
-
,\h:~
:2.~t
/1J:,.;;.<!.
,
42
hI?
Ix~
~..f"
AbG,«
a
Ab....
Cc/)lI.<,;
RYcIO<J;
C-ol~t
C
,~
+-
1""4+
3
0
8dQo.lJ
'1
'l.~
&~
-J
3V
~f!J0'<;
K?
2<:k
3:+ic
»
I
'tCk
I
s:.,R
I
(,q~
I
7t7~
i4'",
Pe,'ceT)t- Oe+l'jfa J
T
(lj(".!
,
2Ci'.,
.~~;.
I
<io.r~
Tf'io.../
co;;.
,
.
7Ck
Detrdc. . . t
fl:,...t..e;')1-
at
.~t'.!
#2.
3~
Pix..€.
2M
Abc...e
~~:e
Abc~'e
C' "'lit;c.t
-0
'-
-+-
d
v
0
-J
/,1
-
&lcv
~
13~1c""
~...1b.c:t
I r=-~.,..
&de-...;
'2.~
6do~
3~.a(klcv
0 ..;
O,b
0.9
,~2
Si/t/Ck)'
13
I-t>
2.'
W(.L b(\.s~ ) Tnl.:l j'({ tl ~
Trio..
Itt I
43
Tf'iG\./
H: 2.
3Fe21
C
I!b..ve.
'2~<rl
AJ,cile
tFi:c+
Ab,;.c,.
~~
Ii!ICI.;l
C<1)iwr...+
I~f-
G:k...
Zr:c:et6eit·...
31e€t
8c!Jo~
I
to1o 10k ,:):"/.
I
~%
Percen+
,
5C;~
&::ic .)(}"
Del-I' ," iu.1
iclo
2c1: ,;:;;; 4D/, SC;J
Perce n+ Oe.tl' /'1cL (
(
TI' /0..1
~Ib!.T
Abc.vc
ttl
fl'ia.1
±t-z..
3fJ:cl
~
'2~i
~~
l~t.
~L
L<"l
(d
0)1
/
,
I. 'l..
IS
S.!f/C/a..y
1,/
bd..
0.'3
o . CI
I.'l.
5;'/f/C
k1
1.5
74'.
-
Appendix C
Stratigraphic Distribution of Silt/Carbonate Ratios
i!.1
Trio.. \
45
triG\., 1 H2
3h:<!t
(~
~.'<-
~~fI.+
t.::... c..
I F'",t
A~;e-
Ab;..:~
C",k,..
&iOJJ
C,.l~
I tu;t'
&feCI.'
2~t
G:J~
3fc\1:t
&lciJ)
0,1
C),3
(',,'--L
Si
C .. li
(;.5
0 .. -
a,i
(),./
o.~s
0.9
It/CQr bexl"'- f..c:...
(,.
Trra.J .i:i:(
3~­
f\~.e,
2ka.~
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Appendix D
Stratigraphic Distribution of Clay/Carbonate Ratios
,
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--
Appendix E
Paleogeographic Setting of
North America During Silurian