Western Michigan University ScholarWorks at WMU
Master's Theses Graduate College
12-1997
Lithological and Stratigraphic Analysis of Glacial Diamictons, Sturgis, Michigan
R. Christopher Gardner
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Recommended Citation Gardner, R. Christopher, "Lithological and Stratigraphic Analysis of Glacial Diamictons, Sturgis, Michigan" (1997). Master's Theses. 4428. https://scholarworks.wmich.edu/masters_theses/4428
This Masters Thesis-Open Access is brought to you for free and open access by the Graduate College at ScholarWorks at WMU. It has been accepted for inclusion in Master's Theses by an authorized administrator of ScholarWorks at WMU. For more information, please contact [email protected]. LITHOLOGIC AND STRATIGRAPHIC ANALYSIS OF GLACIAL DIAMICTONS, STURGIS, MICHIGAN
by R. Christopher Gardner
A Thesis Submitted to the Faculty of The Graduate College in partial fulfillment of the requirements for the Degree of Master of Science Department of Geology
Western Michigan University Kalamazoo, Michigan December 1997 Copyright by R. Christopher Gardner 1997 ACKNOWLEDGMENTS
I would like to thank Dr. Kehew for his continuous support and guidance for this project and throughout my graduate career. My committee advisors, Dr. Harrison and Dr. Barnes, deserve recognition for their critques, interest, and borrowed books. Without Dr. Grace's presence and instruction, ts project may have never gotten off the ground. Accolades to the Geology department staff which never held back in helping me with various problems, thus the research and writing kept moving along. Linda Nicks deserves much thanks for sharing her knowledge of glacial geology at any time without notice and being a comrade in the trenches. Most of all I need to commend my soon to be wife, Sky Atwood, for her love support throughout my college career. Her actons went well beyond my expectations, without which, I could stll be in Kalamazoo today.
R Christopher Gardner
ii LITHOLOGIC AND STRATIGRAPIDC ANALYSIS OF GLACIAL DIAMICTONS, STURGIS, MICHIGAN
R. Christopher Gardner, M.S
Western Michigan University, 1997
Seven diamictons are identified in the subsurface glacial drift near
Sturgis, Michigan using textural analyses and x-ray diffraction of clay minerals. The clay mineral content is quantified by comparing the 7-A/10-
A peak height ratios from x-ray diffraction diffractograms of oriented clay size particle ( <2um) mounts. Two diamictons occur at the base of the drift.
Unit 1 is gray , resembling the shale it overlies. The texture of Unit 1 is sandy clay loam to loam and average 7-A/10-A peak height clay mineral ratios of 0.446 ±0.069. Unit 2 is a yellowish-brown diamicton, it overlies
Unit 1, and is a sandy loam to loam with average 7-A/10-A clay mineral ratio of 0.657 ±0.151. Diamicton Units 4 and 5 overlie a thick unit of sand and gravel on top of Unit 2. Units 4 and 5 have similar color and texture, however the 7-A/10-A ratios are 1.059 ±0.090 and 0.810 ±0.072 respectively.
Unit 6 is a thin diamicton unit, leached of calcite, and x-ray diffraction suggests that there is a range of weathering horzins between borings. Unit
7 is loamy, whereas Unit 8 generally ranges from sandy clay loam to sandy loam with average 7-A/10-A ratios of 0.865 ±0.090 and 1.195 ±0.189. TABLE OF CONENS
ACKNOWLEDGMENTS...... ii
LIST OF TABLES...... vi
LIST OF FIGURES...... Vll
LIST OF PLATES...... ix
CHAPTER
I. INTRODUCTION ...... 1 Introduction...... 1 Location and Regional Glacial Geologic Setting...... 2 Laboratory Analysis...... 6
Textural Analysis Procedure ...... 6
Hydrometer Method...... 8
X-Ray Diffracton of Clay...... 11 Sample Preparaton and X-Ray Diffraction Procedure...... 16 X-Ray Diffaction Procedure...... 18
I. GEOL(Y ...... 20
Bedrock Geology ...... 20 Glacial Geology...... 24
Surficial Geology of Southwest Michigan and Northern Indiana ...... 24 Glacial History ...... 27
iii Table of Contents-continued
CHAPTER
7-A/10-A Variation of Diamicton Units...... 33 Ill. RE SUL TS...... 38
X-Ray Diffraction and Textural Analysis Results...... 38 Unit 1 and Unit 2 ...... 38 Unit 3, Unit 4, and Unit 5...... 45 Unit 6...... 46
Unit 7 and Unit 8 ...... 51 Correlation of Unit 8 to the Fulton Till of Monaghan and Larson (1986) ...... :...... 56
Correlation to Unpublished Data...... 57 IV. DISCUSSION...... 58
Unit 1 and Unit 2...... 59
Unit 4 and Unit 5...... 60 Unit6...... 60
Unit 7 and Unit 8...... 61 V. CONCLUSIONS...... 62 APPENDICES
A. 7-A/10-A Ratio Statistics...... 66 B. Textural Analysis Results...... 69
C. W-46 Textural and X-Ray Diffraction Results...... 72
D. W-44 Textural and X-Ray Diffraction Results...... 76
iv Table of Contents-ontinued
APPENDICE S
E. W-45 Textural_ and X-Ray Diffraction Results...... 80
F. W-43 Textural and X-Ray Diffraction Results...... 83
G. Student-t Test Explanation...... 85 H. Student-t Test Results Comparing 7-A/10-A Ratios Within Each Boring ...... 88
I. Student-t Test Results Comparing 7-A/10-A Ratios Between Units and Landforms...... 91 J. Hydrometer Result Analysis...... 93
K. Centifuge Extracton of Particles Greater Than Clay-Size From Solution...... 95
BIBLIOG RAPHY...... 98
V LIST OF TABLES
1. Clay-Type and X-Ray Diffraction Properties...... 13 2. X- Ray Diffractometer Settings...... _...... 18 3. Student t-Test Comparing 7-A/10-A Ratios Between Borings, #1 ...... 41 4. Student t-Test Comparing 7-A/10-A Ratios Between Borings, #2 ...... 50 5. Student t-Test Comparing 7-A/10-A Ratios Between Borings, #3 ...... 54 6. 7-A/10-A Ratio Statistics...... 67 7. Textural Analysis Results...... 70 8. W-46 Textural and X-Ray Diffraction Results...... 73 9. W-44 Textural and X-Ray Diffraction Results...... 77 10. W-45 Textural and X-Ray Diffraction Results...... 81 11. W-43 Textural and X-Ray Diffraction Results...... 84 12. Student-t Test Results Comparing 7-A/10-A Ratios Within Each Boring...... 89 13. Student-t Test Results Comparing 7-A/10-A Ratios Between Units and Landforms...... 92 14. Centrifuge Spin Times at 1500 RPM...... 97
vi LIST OF FIGURES
1. Surface Geology of St. Joseph County...... 3 2. Close Up of the U.S.G.S. Sturgis 7-1/2 Minute Quadrangle Showing Boring Locations...... 4 3. Regional Moraine Location...... 5 4. Example of the 7-A/10-A Peak Height Ratio Calculation...... 13 5. Diagram Showing the Complexity of Clay Mineral Alteration...... 14 6. Bedrock Geologic Map of Michigan...... 21 7. Bedrock Topography of St. Joseph County...... 23 8. Moraine Name and Location in Southwest Michigan and Northern Indiana ...... 25 9. Examples of Unit 1 Diffractograms and 7-A/10-A Peak Height Ratio Values...... 39 10. Textural Results of Unit 1 and Unit 2 ...... 42 11. Examples of Unit 2 Diffractograms and 7-A/10-A Peak Height Ratio Values...... 44 12. Textural Results of Unit4 and Unit 5 ...... 47 13. Examples of Unit 4 Diffractograms and 7-A/10-A Peak Height Ratio Values...... 48 14. Examples of Unit 5 Diffractograms and 7-A/10-A Peak Height Ratio Values...... 49 15. Textural Results of Unit 7 and Unit 8 ...... 52 16. Examples of Unit 7 Diffractograms and 7-A/10-A Peak Height Ratio Values...... 53
vii List of Figures-continued
17. Examples of Unit 8 Difractograms and 7-A/10-A Peak Height Ratio Values...... 55
viii UST OF PLATES
1. Plate 1...... 102
ix CHAPTER I
INTRODUCTION
Introduction
The surface and subsurface glacial geology of St. Joseph County is currently being mapped as part of a STATEMAP project sponsored by the U.S. Geological Survey. Although the surface geology has been mapped at a small scale, the subsurface glacial geology of St. Joseph county has never been studied in detail. The origin of glacial drift in southwestern Michigan is difficult to determine because of the interaction of three independent glacial lobes from the Laurentide ice sheet that advanced and retreated many times over the State during the Pleistocene. The purpose of this study is to employ analytical techniques to identify and correlate distinct subsurface units near Sturgis in St. Joseph County. Diamicton samples were taken from four borings continuously sampled from ground surface to near bedrock depths using the double walled reverse air rotary drilling method. Samples were analyzed for clay mineral content by comparing the 7-A and 10-A peak heights from x-ray diffraction analysis. Texture was determined using the sieve and hydrometer method. Monaghan and Larson (1986) successfully used x-ray diffraction techniques and textural relationships to differentiate diamicton units in an adjoining region north of the study area. Rieck (1979) also used x-ray diffraction to differentiate glacial drift in southeastern Michigan.
1 2 The primary goal of the study is to evaluate analytical techniques used to determine the glacial stratigraphy of the study area by correlating diamicton units between borings. An understanding of the glacial stratigraphy is essential for interpretation of the glacial history and for delineation of aquifer units. The mineralogy of the Diamicton units relates to the bedrock and glacial units eroded by the glacier. The texture relates to the lithology of units overridden by glacial transport. Assuming that diamicton units have different sources, the clay mineralogy and texture may be used to identify and correlate diamictons. Results from this study are compared to results from the work of Monaghan and Larson (1986) and ongoing stratigraphic correlation in northern Indiana and St. Joseph County.
Location and Regional Glacial Geologic Setting
The detailed study area lies within the city of Sturgis, Michigan about three miles north of the Indiana-Michigan border (Figures 1, 2, 3).
St. Joseph County is underlain by glacial drift ranging from 100 to 300 feet thick overlying the Coldwater Shale. The Sturgis Moraine (Figures 1, 3) is present in two areas in the county. A northwest trending moraine, of probable Saginaw Lobe origin, is located in the southeastern corner of the county, 1 mile northeast of the detailed study area. A north-south trending moraine exists along the western edge of St. Joseph County and adjacent Cass County west of the study site. Outwash dominates the surfacial sediment of St. Joseph County between morainal ridges. 3
Sturgis Moraine (Saginaw Lobe) [ill TTll Plains Sturgis Moraine (Michigan Lobe) F:7:llid Spillw�-;- Outwash and □ Glacial Channels
Figure 1. Surface Geologyof St. Joseph County. Source: Adapted from G.E.M., Walking on Water. 4
70 1os::o::=10E==2 :3 =' 5 6 = FEET i: E= ===:==c:
CONTOUR INTERVAL 10 FEET
Figure 2. Oos Up of the U.S.G.S. Sturgis 7-1/2 Minute Quadangle Showing Boring Locatons. -..J -..J "'{ "'{ � � 1<.i - ,,_ ,,_ . . > > � ... � � :::: ... I,:) I,:) � � � - i i I I .. .. -c• .s. .:1 i .r .r ,:- .. .. , , ·= ' i .. .. IIl)�l]� IIl)�l]� s s i "Ii "Ii ,; ,; & & ...... ' ' . flffl0N1 : flffl0N1 ' ' OIMO j j • i i l . . .J .J . . • • .: .: ·• ·• s s "Ii .i .i ... .i .i & & ...... I I . .. .. '; E : : . . a a : : ;; ;; • • \ \ ...... 0 0 1 1 .! �\ �\ l :a :a ,. ,. l i . . ' ' . l l i i 1 . . -- ,-l ,-l -- ...... "So C: C: 0 0 � � I': 0 0 u c:: c:: Cl,) Clj Clj I': I': 0 0 -- ce ce 0 0 c:: (lJ (lJ (lJ (lJ bO bO :::l ,,_, ,,_, � � ...... "O "O "O "O (l) (l) � � .. t.O � � (l) (l) 5 5 :::l :::l 0 0 � � 5 5 6 The four borings were drilled in the western city limits of Sturgis. The borings are located on an outwash fan, sloping south from the Sturgis Moraine. The surface elevation of W-46, the highest boring, is 908.6 feet above sea level. At boring W-44, 1500 feet south of W-46, the surface elevation is 904.4. W-45, 1500 feet south of W-44, is at 901.2 feet above sea level and W-43 is 4200 feet southeast of W-45 at 900 feet above sea level. The extended study area (Figure 3) includes Saginaw Lobe drift in Eaton, Calhoun, and St. Joseph Counties, Michigan and counties in Northern Indiana. Lake Michigan Lobe deposits included in this study were sampled in Allegan, Van Buren, Barry, Kalamazoo, and Cass Counties.
Laboratory Analysis
Textural Analysis Procedure
Textural analysis of diamicton samples involved a combination of two procedures. Sieve analysis (Wray, 1986) was used to determine the grain size distribution of the gravels and sands. Data from the sieve analysis was used to calculate the initial sample size for the hydrometer test. The hydrometer method is used to grade silt and clay size particles using the differential settling velocities of fine sand, silt, and clay ( <2um). A hydrometer bulb was used to measure the density of the solution as the material settled in a jar at specific time intervals (Wray, 1986). Data from the mechanical and hydrometer analyses were combined to determine the percentages of fine sand, medium sand, coarse sand, total sand, silt, and clay in the diamicton samples. Gravel was not included in the calculations 7 because sample sizes were not large enough to include a representative amount of gravel. Mechanical Analysis Procedures
The following method is modified from Wray (1986):
1. Sample 350 to 400 g of diamicton material at field moisture and break up with fingers onto a sieve pan. Label and place the pan into oven at 105 degrees Celsius for 6 to 12 hours to dehydrate the material.
2. Transfer some material from the sieve pan into a porcelain mortar and pound the material with a porcelain pestle breaking it into pea-sized pieces. Care should b taken not to grind coarse partcles into finer material. Further grinding is done with a rubber-tpped pestle and worked material is transferred to a weighting tray.
3. Once all dry material is worked with mortar and pestle, the dry weight of the sample is recorded as dry total. Material is then transferred to a mechanical stirring cup. A pinch of sodium hexa-metaphosphate
( calgon) is added as a dispersant. The dispersant satisfies the surface charges on the clay and prevents flocculation of the clay. Tap water is added to fill the stirring cup three-quarters full. The cup is placed in the mechanical stirrer and agitated 5 to 10 minutes.
4. Material and water from the cup are poured into a #230 sieve.
The material in the cup is rinsed into the sieve and tap water is run through the sieve until the runoff appears clear. The silt and clay are washed from the sand and gravel. The sand is transferred to a pan and allowed to evaporate in the oven.
5. The dry sand is then weighed and recorded as total sand. Sieves are stacked from top to bottom as follows: #4, #10, #20, #40, #100, #230, 8 pan and the dry sand are transferred to this sieve stack. The sieve stack is then put into the Roto-tap machine and agitated for 10 minutes.
6. The material retained on each sieve is weighed, recorded, and stored. The amount washed is calculated by subtracting the total sand from the dry total. The acquired data is then entered into a spread sheet. Gravel is retained on the #4 sieve. Coarse sand is retained on the #10 sieve; medium sand on the #20 and #40 sieves; and fine sands are retained on the #100 and #230 sieves.
Hydrometer Method
1. The data acquired from mechanical analysis is used to calculate the size of the sample to acquire from the dy bulk sample. The weight of the sample must be calculated so that it contains between 50 and 60g of dry material that is finer than the #100 sieve. Do not use material saved from the sieve analysis. To calculate the weight in grams to sample, 5700 divided by the percent dry material finer than the #100 sieve from the mechanical procedure. Work appropriate size dry sample with mortar and rubber-tipped pestle. Do not grind sample with porcelain pestle; use only the porcelain pestle to punch the sample to pea size aggregates before using rubber-tipped pestle to grind the sample.
2. Transfer sample to the mechanical stirring cup and fill cup 1/4 full with tap water. Place the cup in the mechanical stirrer fr 5 to 10 minutes.
3. Place a #100 sieve over a sieve pan. Pour the contents of the stirring cup into the #100 sieve and rinse the material in the cup into the 9 sieve with a squirt bottle. Material finer than the #100 sieve is retained in the pan. Wash the sample in the sieve with water until all of the silt and clay have washed into the pan. 4. The pan is then placed in the oven for 24 hours until completely evaporated, forming a cracked silt and clay cake layer on the pan. 5. Transfer the material from the pan to the weighing tray by lifting and scraping the sediment from the pan with a microspatula and a stiff paint brush. Grind the sample with a rubber-tipped pestle and transfer the sample to the small weighing tray. 6. Weigh the crushed hydrometer sample to nearest 1/100 gram using the dial scale and record as Ws. The dry Ws sample must be between 50 and 60 grams or the hydrometer results are invalid. Transfer the hydrometer sample into a beaker. 7. At 12 to 6 hours before the beginning of the test, the sample is hydrated. Add 125 ml of 4% sodium hexa-metaphosphate and 50 to 100 ml distilled water to the hydrometer sample. Stir the sample, hydrating the dry material, then place the sample beaker into the ultrasound bath for 5 to 10 minutes. Cover and let sample soak 12 to 6 hours before test. 8. The 4% sodium hexa-metaphosphate solution is the dispersant used to prevent the clay from flocculating. The 4% sodium hexa metaphosphate solution is created by pouring 950 ml distilled water into a 1000 ml graduated cylinder. The cylinder is placed on a stirring plate and a magnetic stirring rod is placed in the water and activated. Add 40 g of granule sodium hexa-metaphosphate to the cylinder. The solution is mixed until the crystals are dissolved, approximately 10 minutes. Top to 10 1000 ml with distilled water plus the volume of the magnetic stirring rod.
Store, label and date dispersant soluton. 4% Sodium hexa-metaphosphate solution is effectve for 30 days.
9. One person can typically perform two hydrometer tests simultaneously. Two more hydrometer tests can be started after about 30 minutes after the beginning of the initial tests without much difficulty.
Thus four samples can be started in one morning. The distilled water and dispersant solution should be acclimated to lab temperature overnight.
10. Stir the samples and then place in the ultrasound bath. Also place a beaker with 125 ml of 4% sodium hexa-metaphosphate dispersant solution into the bath. Actvate the ultrasound for a few minutes.
11. Prepare one control jar for each pair of hydrometer samples.
Pour the dispersant only solution that was in the bath into a 1000 ml graduated cylinder. Top the cylinder to 1000 ml with distilled water.
12. Pour the hydrometer sample into the 1000 ml hydrometer jar and, using a distlled water squirt bottle, wash the remaining material in the sample beaker into the hydrometer jar. Top the hydrometer jar to the
1000 ml mark with distilled water.
13. Take the temperature of the control jar and hydrometer jars. The following instructions assume that two test will be performed simultaneously using hydrometer jars A and B. The test may begin when the temperatures of the solution in the jars are within 0.5 degrees Celsius of one another.
14. Place a stopper on jar A. For one minute, mix jar A by inverting the jar slowly then righting it again slowly. Start the timer after going 11 from an inverted position to setting the jar on the table. Remove the stopper. 15. Readings will be taken exactly at minutes 1, 2, 4, and 8 fom the beginning of the hydrometer test for each of two jars. The reading of the second jar occurs 1.5 minutes after the reading of the frst jar. Repeat steps 14 and 15 until 2 identical results are achieved, then continue with step 16. 16. Readings will the be taken exactly at minutes 16, 30, 60, and 120 and at approximately 4, 8, 16, and 24 hours from the beginning of the hydrometer test fr each of two jars. 17. Fifteen to 30 seconds before the time of measurement the hydrometer bulb is slowly lowered into the sample solution. The suspension is disturbed as little as possible. The hydrometer reading is taken where the meniscus rises on the hydrometer bulb to the nearest 1/4 unit and recorded. 18. After readings are taken on the hydrometer jars, temperature and hydrometer reading should be taken on the control jar and recorded. All jars are covered with a watch glass to prevent evaporation between measurements. 19. The data collected are input onto an Excel spread sheet and the percent silt and clay are calculated from the hydrometer measurements. The formulas for the calculations are located in Appendix K.
X-ray Diffraction of Clay
X-ray diffraction of clay minerals can provide both semi quantitative and qualitative mineralogical data and is the method of 12 choice for clay mineral analysis. Diffracton peaks are produced when x rays are reflected off a layered structure and create constructive interference patterns. As the x-rays are directed toward the sample, the detector is rotated through an arc about the sample. The 20° position of the detector corresponds to the x-axis units on the diffractogram (Figure. 4). Where a crystal lattice has a series of parallel layers of atoms with a given d-spacing, constructive x-ray interference patterns will be produced. These constructive patterns are read by the detector at a specific angle from the plane of the sample. The constructive interference produces the peaks along the y-axis of the diffractogram as the x-axis corresponds to the 20 ° rotation of the detector. Clay typically has a layered structure. Each clay type has a specific distance between each layer referred to as the d-spacing. The d-spacing depends on the type of clay structure. The d-spacing of the layers controls the 20° angle at which peaks are produced on the diffractogram. The (001) and (002) d-spacing is used to semi-qualitatively determine clay types (Table 1). Diffraction analysis without various sample treatment is semi qualitative because the 7-A peaks overlap fr chlorite and kaolinite and the 14-A peak overlaps for chlorite and vermiculite. Most clay minerals are secondary weathering products of aluminosilicates and other clay minerals. Figure 5 demonstrates the complexity in the formation of clay minerals. During interglacials, sequential weathering of aluminosilicates and clay associated with glacial drift and bedrock produced distinct clay 13
Table 1 Clay-Type X-Ray Dfacon Proprtes
Clay /Stucture 28° (001) d-spacg Intensit
7A Kaolinte 1:1 12.6° 10 Ilite 2:1 8.85° l0A 10 Chlorite 2:1 (001) 6.35° 14A 6 7A Chlorite 2:1 (002) 12.6° 10 Vermicuite 2:1 6.35° 14A 10
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• 0 7-A/10-A Peak Height Ratio 36mm/ 42 mm 0.857
Figure 4. Example of the 7-A/lOA Peak Height Rato Calculaton. Hot wet climates (-SI) Rapid removal of bases i i M crocl ne Much Mg In weathering zone Orthoclase t -K -K � I and o hers -- ite -- Ill �i' K r ------· J I _ -K + l i : l__ Muscov te _!Oxidesof '. � I l �enniculite.Jitontmonl on,te-Kao te I . � _ hm Fe and Al Micas f lf . . ... V i T -Mg - Biot te --_-K,1 -7 -ct- 00 � ------Chlorit I ei _ � ..cl::E ro � Soda-l m Slow removal of bases Mg present eoZ Feldspars Rapid removal ol bases =B d A Hot wet climates (- SI) ugite e Hornblend and others Degree ol weathering Increases
Figure 5. Diagram Showing the Complexity of Clay Mineral Alteration. Source: Adapted from Brady (1990)...... � 15 mineral combinations for each interglacial. Thus each glacial advance along the same flow path may incorporate a distinctly different clay combinations than the previous advance. These differences in clay mineralogy are reflected in differences in the 7-A/lOA peak height ratios between diamicton units deposited by each glacial advance. This ratio provides a measure for comparison of the amount of chlorite and kaolinite to illite, which is significant because illite and chlorite are the initial weathering products of aluminosilicates. Illite weathers from minerals high in potassium and chlorite from minerals high in Mg, Ca, Na, and Fe. Under most weathering environments, kaolinite is the final clay weathering product before bauxite and gibbsite (Al & Fe oxides) are produced. With an increase in the quantity of a specific clay, the peak will become higher, more intense. Semi-quantitative analysis of the amount of clay can therefore be made by measuring peak height. This method cannot be used to precisely determine the amount of each clay present because the degree of crystallinity and thickness of the clay mineral and the presence of polymorphs of a specific clay also affect peak heights. Peak area would yeild a more reliable 7-A/lOA ratio. Dispersed clay in a suspension settles in a sheet-like array. A glass slide of dried dispersed clay is called an oriented mount. Because it is a weathering product, clay does not produce as good of an x-ray diffraction pattern as other crystalline structures. To overcome the weakness of clay particles to reflect x-rays, all clay particles are oriented parallel to the glass slide by allowing dispersed clay to settle and dry on the slides. This method 16 enhances the x-ray peaks because the clay grains oriented similarly offer a
continuous surface to reflect x-rays. The flocculated or random mount clay
sample provides an imperfect surface and produces weaker x-ray peaks.
Sample Preparation and X-Ray DiffractionProcedure
The following procedure was followed to prepare and x-ray clay-size
diamicton particles mounted to a glass slide. This method is modified
from Carrol (1970) and Starkey (1984).
1. Dry approximately 25 to 30g of diamicton sample in an oven.
2. Crush the dried sample in a mortar with a porcelain pestle to pea
size aggregates then reduce to silt size with rubber-tipped pestle. Transfer material to the stirring cup with 25 ml of _ 4% sodium hexa-metaphosphate
solution and 50 ml distilled water. Mix the sample in the mechanical
stirrer for 5 to 10 minutes. Place a sieve pan below a #230 sieve.
3. Pour the contents of the stirring cup into the sieve. Rinse the
remaining material in the cup with a minimum amount of distilled water from a squirt bottle into the sieve. Rinse the sand in the sieve using the
distilled water squirt bottle until 100 to 150 ml of silt and clay solution is
accumulated in the pan. The silt and clay suspension collected in the sieve pan is transferred to a beaker.
4. The beaker is placed into the ultrasound bath fr 5 to 10 minutes.
The sample is then transferred to two centrifuge tubes and the beaker is
rinsed. The centrifuge accompanies 4 cups, so 2 samples are separated simultaneously. Place the centrifuge cups into the centifuge unit and
record the cup holder number on the sample beaker. 17 5. Take the temperature of the samples in the centrifuge cups. Consult a table (see Appendix L) which indicates how long to spin a sample at the measured temperature calibrated fr the particular centifuge and cup being used. Engage the centifuge, 1500 RPMs for this study. As the centrifuge spins, the silt is being frced to the bottom of the cup while the clay-sized particles remain in suspension. Disengage the centrifuge at the appropriate time and apply the brake to bring the cups to a stop 30 seconds after disengagement. Carefully pour the suspension from the centrifuge cup to the beaker. 6. Place the beaker into the ultrasound bath for 5 minutes. 7. Prepare 2 glass slides for each sample by indicating the sample name with a sharpie on the bottom of each slide. Place the slides on plastic film canisters in a dust free drying area. Stir the sample and pipette between 0.5 and 2 ml onto the slide; the readability test is used to estimate the correct amount of suspension to pipette on the slide. The sharpie label on the bottom of the slide should be visible but not readable when looking at the slide from top. Record the amount of suspension pipetted onto the slide. Allow slide to dry 12 to 24 hours. 8. A god clay glass slide mount is flat, smooth, and opaque. If the material peels away from the slide, too much material was pipetted onto the slide. If the sharpie label can be seen through the clay, too little clay was pipetted. To remount the clay sample, clean the glass slide with water and place the sample beaker in the ultrasound bath for 5 minutes and repeat step 7 pipetting more or less suspension onto the slide. 18 X-Ray DiffractionProcedure
1. Bring the x-ray generator to 30 m Volts and 20 mAmps in a
stepwise manner never letting amps exceed volts. A Norelco XRD
machine was used for ths study. The following settings were followed:
Table 2
X-Ray Diffractometer Settings
Adjustment Value
diversion slit 0.5° goniometer speed 0.5° /minute Prop. KV 1.6 gain 256 range lK time constant 2
2. Load the oriented glass slide sample into the x-ray chamber and secure the chamber cover. Check the chamber cover for a secure fit. With the clutch disengaged, turn on the switch that starts the goniometer rotating and start the graph chart rolling with the pen down. Crank the goniometer to the startig position at 7.5 degrees. When the pen on the moving chart reaches a heavy whole unit line, engage the clutch to start the goniometer rotaton. One minor unit on the graph represents 1/l0th of a degree. Two major units (or 10 minor units) make one degree of rotation. The goniometer and chart graph should be on the same whole 19 units. For example when the goniometer starts at 7.5 degrees the chart will be on a major unit line. 3. The sample is typically run from 7.5 to 12.5 degrees. When finished, the sample is the rotated 180 degrees in the sample chamber and x-rayed again. Two more passes are made with the second slide. Four diffractograms should be created on one continuous chart. 5. Hand sketch in a baseline, an estimation of the path that would be graphed if the peaks were not present. Measure the peak heights from the baseline to the nearest half millimeter. The 7-A peak occurs at approximately 12.65 degrees and the 10 A peak at 8.85 degrees. Divide the 7-A peak by the 10-A peak and record the average ratio of all four passes. CHAPTERII
GEOLOGY
Bedrock Geology
Bedrock stratigraphy in the Southern Peninsula of Michigan and the eastern half of the Northern Peninsula forms a bowl-shaped depression known as the Michigan Basin; sandstone, shale, carbonate, and evaporite formations deposited between the Cambrian and Carboniferous periods occur in this structure (Wayne and Zumberge, 1965). The subcrop distribution of these units is shown in Figure 6. The Mississippian Coldwater Shale underlies the drift (WMU, Department of Geology, 1981) in the southern part of the study area, the gray to blue shale contains iron concretions within thin interbeded limestone and dolomite (Shah, 1971). The Coldwater shale grades upward into the lower Marshall Sandstone, which is comprised of sandstone and siltstone forming a 15-mile wide subcrop northeast of the Coldwater Shale beneath the drift in Barry and Calhoun Counties. The Upper Mississippian Michigan Formation, which overlies the Marshall, subcrops in an approximately five-mile wide area; the unit is comprised of shale, gypsum, dolomite, limestone, and a some sandstone. The Michigan Formation outcrop pattern lies parallel to the Marshall Sandstone. The Lower Pennsylvanian Saginaw Formation which is comprised of sand, silt, clay, shales, limestones and coal (Dorr and Eschman, 1970), subcrops
20 21
hwnsl Pr G Riv Pl SGQinaw "'- ,,. Mb B Mm M Mnm �-Mannan Mc CGlchlalw Mbb a-Blf Mc E1-Anl �� M-Oo Am � Dt Trawne Ore Row Cty 0d OH Odr Olt Ri- Obb S 8 �sa-... D·Sm Minc l Silariaa Sbi Bas Islnd Ss St. lgnoca Sp Paint Awl� Se Ein Sm Mqu Sbb Bt Bluff S• Mvill � Or Richmo 0c Collingwood ' 01 Tl'ln!On Obr Bla Rive Oh Hensvill c...... Cm Munisng Cj Jsville � MIL C Cmban univde
Figue 6. Bedock Geologic Map of Michgan. Suce: Dorr (1970) 22 beneath the drift in the northeastern part of the study area to the Saginaw Bay. A bedrock topographic map, adapted fom the Michigan Department of Natural Resources (1943) by the W.M.U. Geology Department (1981), provides general state-wide bedrock topographic tends. East of the study area, a bedrock ridge runs northeast with a high of more than 1100 feet above sea level in Branch and Hillsdale counties. Te ridge descends northeast to an elevation of approximately 700 feet in Huron County. In southwest Michigan, bedrock topography generally dips toward the center of the basin. A bedrock valley was mapped between northeast Cass County and northwest St. Joseph County at a depth between 500 and 450 feet (Figure 7). A noncontinuous valley of similar depth is depicted in southeast St. Joseph County. Bedrock elevation is shown descending form the southwest corner of St. Joseph County to approximately 550 feet in the center of the county to 750 feet in the northeast corner of the county (W.M.U. Geology Department, 1981). Figure 7 may not accurately represent bedrock topography at a local level. Borings used in this study were approximately 250 feet deep to near bedrock depths near the western Sturgis city limits. The Sturgis area directly overlies the bedrock valley mapped between 450 and 500 feet above sea level, but the borings show bedrock depth shallower, at approximately 650 feet. It should be noted that borings may not have gone to bedrock but stopped at a Coldwater boulder within the drift near 23 �-
I •.
i I 0 60 I . / : 65 0 / 'i--1---_--_ _{_�-- .. -·-·
Figure 7. BedrockTopography of St. Joseph County. Source: Western Michigan University Geology Department (1981). 24 bedrock. A more accurate bedrock map of the couty is to be produced by
Linda Nicks in her doctoral dissertaton.
Glacal Geology
Surficial Geolog of Southwest Mihigan and Northern Indiana
The surfcial sediments in the study area were deposited by both the Lake Michgan and Saginaw Lobes during the Wisconsin Episode (Leverett and Taylor, 1915; Zumberge 1960; Farrand, 1970; Monaghan and Larson, 1986). The Kalamazoo Moraine system is an extensive ridge that was formed by both the Lake Michigan and Saginaw Lobes (Figure 8) (Leverett and Taylor, 1915; Zumberge 1960; Monaghan and Larson, 1986). The Kalamazoo Moraine of the Lake Michigan Lobe is separated into two parallel ridges referred to as the inner and outer ridge. The morainal ridges trend northeast through Cass, Van Buren, Kalamazoo, and Barry Counties. The Kalamazoo Moraine of te Saginaw Lobe trends northwest southeast in Barry, Eaton, Kalamazoo, Calhoun and Jackson Counties, and joins the Erie Lobe Mississinawana Moraine in wester Washtenaw County. The two segments of the Tekonsha Moraine are also thought to have been deposited by the Lake Michgan and Saginaw lobes (Leverett and Taylor, 1915; Zumberge 1960; and Monaghan and Larson, 1986), but this has been disputed (Dodson, 1993). In east central Kalamazoo County, the northeast tending, wester segment of the moraine joins with the northwest trending, eastern segment of the moraine. The eastern segment 25
Figure 8. Moraine Name and Locaton in Southwest Michigan and Northern Indiana.
Surce: Adapted from Leverette and Taylor (1915). 26 runs from the northeast corner of Branch County through the middle of the western border of Calhoun County. Leverett and Taylor (1915), Zumberge (1960), Monaghan and Larson (1986) agreed that the Saginaw Lobe formed the eastern segment as the western segment was being formed by the Lake Michigan Lobe; but Dodson (1993) suggests that the western landform is a collapsed outwash plain/kame moraine of Saginaw Lobe origin formed when the Lake Michigan Lobe was close to the west. The Leonidas drumlin field, also known as the Union Streamlined Plain (Dodson, 1993) lies near the junction of Kalamazoo, Calhoun, Branch, and St. Joseph Counties, southwest of the Tekonsha Moraine on a diamicton plain. The Sturgis Moraine is also composed of two segments. The moraine formed by the Saginaw Lobe (Zumberge 1960; Monaghan and Larson, 1986) trends northwest from the southeast corner of St.Joseph County to the center of the county. The segment associated with the Lake Michigan Lobe trends to the north along the northern 3/4 of the western border of St. Joseph County and into Cass County. Sand covered lowlands are found in most areas of St. Joseph County between morainal ridges. Northeast of the Saginaw Lobe Sturgis Moraine lies a succession of landforms including a sand covered lowland, a series of discontinuous hummocky to rolling upland tracts, and the drumlin plain in the northeast corner of the county (Kehew, 1997). Saginaw Lobe deposits extend into LaGrange and Elkhart Counties, Indiana. The Shipshewana Moraine trends northwest from central of LaGrange County to the northwestern corner and into the northeastern 27 corner of Elkhart County. The Shipshewana Moraine is thought to be a push moraine (Flemming, 1997). The Newbury Moraine, which is just south and parallel to the Shipshewana Moraine, is only found in the southwestern corner of the county. The Middlebury Moraine also trends northwesterly from the southwestern corner of LaGrange County to north-central Elkhart County. The Mississinewa Moraine in the southeastern corner of LaGrange County was formed by the Erie Lobe. Outwash covers the land surface between morainal uplands throughout LaGrange County. A thin surface diamicton overlies outwash fans associated with the Sturgis and the Shipshewana Moraines and the Erie Lobe Topeka fan. The diamicton also caps hummocky uplands in the area (Nicks et al., 1997).
Glacial History
The Quaternary of the Great Lakes region is divided by episodes of glacial advance and retreat. Initially, pre-Illinois Episode glacial ice advanced and was followed by an interglacial. The climate cooled again and during the Illinois Episode, ice advanced south to the Ohio River Valley. The most recent diachronic and event nomenclature is integrated from Johnson et al. (1997). Lineback (1979 from Johnson, 1986), based on stratigraphy, concluded the Illinois Episode to of had interglacial cycles and began between 500 and 400 thousand years ago. Using the 180 analysis of the marine record, the Illinois Episode is estimated to have began 302 thousand sidereal years ago (Johnson, 1986). Ending the Illinois Episode 28 was the warm Sangamon Episode, during which a thick, widespread soil developed. Following the Sangamon Episode, the Wisconsin Episode contained many times of glacial advance and retreat but is only divided into two subepisodes in the southern Great Lakes region. The Athens Subepisode replaces the period formerly referred to as the Early Wisconsin. It was followed by the Michigan Subepisode which began in Michigan approximately 28,000 years ago (Johnson et al., 1997). Organic beds overlying a diamicton, thought to date from the Athens Subepisode, were found near Grand Rapids, Michigan and were dated at 51,000 BP (GrN- 4614; Johnson, 1986). A diamicton at the base of a Lake Michigan bluff near Glenn Shores, Michigan contained organic matter dated at 37,150 +- 540 BP (Beta-3311; Monaghan, 1986) to >48,000 BP (ISGS-948; Gephart et al., 1983). The Wisconsin Episode was recognized to have at least five advances and four interglacials (Monaghan and Larson, 1990), within the Athens and Michigan Subepisodes. During the MichiganSubepisode, glacial ice advanced and retreated across Michigan as three independent lobes of ice; the Lake Michigan Lobe, the Saginaw Lobe, and the Huron-Erie Lobe. The shapes of these lobes were controlled by the deep basins of Lake Michigan, Saginaw Bay, and Lake Erie, respectively (Farrand and Eschman, 1974). These lobes controlled glacial deposition in Illinois, Indiana, Michigan, and Ohio. The maximum extent of glacial ice during the Wisconsin Episode reached the northern edge of the Ohio River Valley between 21,000 and 18,200 years ago (Dreimanis, 1977), where the Shelbyville and Mt. Olive Moraine 29 Systems were deposited during the Michigan Subepisode. Recent investigations conclude that during the Michigan Subepisode, a warm period known as the Erie lnterstade began 15,500 years ago (Monaghan, 1990). Zumberge (1960) concluded that the Lake Michigan Lobe formed the Minooka and Marseilles Moraines in Illinois while the Saginaw Lobe was at the Iroquois Moraine, and the Erie Lobe at the Union City and Packerton Moraines (Figure 3). Befre the Erie lnterstade, Monaghan and Larson (1986) suggested that the Lake Michigan Lobe ice was located at the Marseilles Moraine and the Tekonsha Moraine (assumed buried in St. Joseph County). The Saginaw Lobe ice was assumed to be at the Sturgis Moraine, and the Erie Lobe at the Bloomington Moraine System in Indiana and Reesville Moraine in Ohio. Leverett (1915) concluded that because the Saginaw Lobe overrode a topographic high; the ice was not as thick and melted quicker than the other lobes. Dreimanis (1977) proposed that if the Saginaw Lobe deposited the Iroquois Moraine, the ice retreated during the Erie Interstade and deposited the Maxinkuckee Moraine as a recessional moraine. As the ice continued to retreated, the Packerton Moraine was being formed in an interlobate position by the Erie Lobe northeast from Carrol County to Whitley County, Indiana (Zumberge, 1960). The Saginaw Lobe retreated further, stagnated and formed the Sturgis Moraine befre the Erie Interstade. The Erie Lobe may have retreated from the Bloomington Moraine System to the Union City Moraine or the Mississinewa Moraine (Zumberge, 1960). 30 The formation of the Middlebury Moraine in eastern Elkhart County, and the Newbury and Shipshewana Moraines in LaGrange County were not included in historical interpretations (Figure 8). Deposition of these moraines may have occurred after formation of Maxinkuckee Moraine and before the Sturgis Moraine. Flemming (1997) felt that the Shipshewana Moraine is a push moraine associated with the terminal advance of a glacier. From the Sturgis Moraine, the Saginaw ice retreated through southeastern Kalamazoo County forming the Wakeshma Till Plain before again pausing or readvancing to the Tekonsha moraine (Martin, 1957). Martin (1957) suggested that the retreating ice also formed the Leonidas Drumlin Field within the Wakeshma Till Plain whereas Shah (1971) concluded that readvancement over the Tekonsha Moraine later in time formed the drumlins. Nicks (1997) believes the drumlins were formed at the same time as the Sturgis Moraine or Shipshewana or Middlebury Moraines, based on the presence of interpreted tunnel valleys that terminate at the Shipshewana and Middlebury Moraines. Leverett and Taylor (1915), along with Farrand and Eschman (1974), concluded that the Lake Michigan and Saginaw Lobe formed the two branches of the Tekonsha Moraine simultaneously during formation of the Minooka and Marseilles Moraines in Illinois. Based on clay mineralogy, Monaghan and Larson (1986) concluded that the same glacial advance deposited both the Leonidas Drumlin Field and the eastern branch of the Tekonsha Moraine while the Lake Michigan Lobe deposited the western branch. Lovan (1977) agreed with this interpretation and 31 placed a boundary on the Tekonsha Moraine between Lake Michigan and
Saginaw Lobe deposits based on clay mineralogy and heavy mineral analysis. The Tekonsha Moraine of the Lake Michigan Lobe maybe buried in southern Kalamazoo and St. Joseph Counties because it is not evident surficially (Kehew et al., 1996).
Using clay mineralogy, Monaghan and Larson (1986) traced a diamicton from its exposure at Glenn Shores, Michigan along the Lake
Michigan shoreline, to the west branch of the Tekonsha Moraine. Dodson
(1993), however, concluded that the west branch of the Tekonsha Moraine is not a moraine in the classic sense but a hummocky and pitted outwash plain/kame moraine of Saginaw Lobe origin, deposited when the Lake
Michigan Lobe was at or near the western edge of the western Tekonsha
Moraine arm. Monaghan and Larson (1986), showed a similarity in clay mineralogy between the Lake Michigan bluff exposures and the western segment. Dodson (1993) demonstrated that the clay mineralogy of the west arm is similar to the surface diamicton of the Leonidas Drumlin Field.
Thus analysis of the clay mineralogy in this area cannot conclusively identify the lobe of origin of the landforms. Dodson (1993) based his conclusions on exposed drift fabric, indicator stones, morphology, and elevation relationships, in addition to clay mineralogy. Thus, the evidence is not conclusive that the Lake Michigan Lobe deposited a now buried north-trending Tekonsha Moraine segment in St. Joseph County.
Morner and Dreimanis (1973) concluded that after the Erie
Interstade, the Lake Michigan Lobe ice had advanced to the Kalamazoo
Sturgis System in Michigan and Valparasio Moraine in Illinois. They also 32 suggested that at this time, the Saginaw Lobe readvanced to the Sturgis
Moraine, and the Erie Lobe to the Powell-Union City Moraine in Indiana.
Leverett and Taylor (1915), along with Farrand and Eschman (1974), and
Rieck (1979) concluded that, after the Erie Interstade, the Saginaw Lobe ice at the Kalamazo Moraine was time equivalent to the Lake Michigan Lobe
formation of the Kalamazoo-Sturgis Moraine and Outer Ridge of the
Valparasio Moraine. During this time the Erie Lobe was inferred to be at the Mississinawa Moraine. Monaghan and Larson (1986) contradicted the above authors, and argued with Morner and Dreimanis (1973) stating that following the Erie Interstade, the Lake Michigan Lobe ice advanced to the
Kalamazoo-Sturgis Moraine and the Erie Lobe advanced to the Powell
Union City Moraine in Indiana. However, Monaghan and Larson (1986) agreed that the Saginaw Lobe formed te east segment of the Kalamazoo
Moraine.
The eastern extent of the Lake Michigan Lobe in Michigan has not been determined with certainty in St. Joseph County between the western segment of the Tekonsha, the Sturgis, and Outer Kalamazoo Moraines before or after the Erie Interstade. Clay mineralogy shows that both parts of the Kalamazoo Moraine were deposited concurrently by the Lake
Michigan and Saginaw Lobes (Monaghan and Larson, 1986). After deposition of the Kalamazoo Morainic System, the Lake Michigan Lobe formed the Valparasio and Lake Border moraine systems during its retreat. The Saginaw Lobe retreated and frmed the Charlotte and Lansing
Moraines. The study area has remained ice free following the reteat of
Michigan Episode ice by 13,300 years ago. By 10,000 years ago, Michigan was 33 ice free after two glacial advances that deposited drift in only northern Michigan (yVayne and Zumberge, 1965). It is evident from previous work that there are many interpretations of the origin and chronology of Wisconsin Episode deposits. With further subsurface analytical investigation of these areas, the glacial history can potentially be unraveled. z-A/10-A Variation of DiamictonU nits
Differences in diamicton and other drift lithologies are caused by differences in provenance, lithologic properties, glacial process, dilution, and interglacial weathering (Anderson, 1955; Rieck 1979). These differences are reflected in diamicton clay mineralogy (Monaghan and Larson, 1986; Rieck, 1979; Lovan, 1977) throughout southern Michigan. To graphically represent the clay mineralogy, the peak intensity of the 7-A peak is divided by the 10-A peak (William et al, 1966). Kaolinite has been observed to remain unaltered by weathering. Thus changes in the ratio within a diamicton or between two units are dependent on the proportions of illite and chlorite. Between two units, the ratio is not only dependent the proportions of illite and chlorite but also on bulk kaolinite content formed as a weathering product. Chlorite, which produces a 7-A peak, is more susceptible to weathering than lOA-illite. Weathering of diamictons reduces the 7-A chlorite peak more than the lOA-illite peak and allows for evaluation of weathering (William et al., 1966). Thus, weathering tends to reduce the 7-A/10-A ratio until illite begins to weather.
... 34 Monaghan (1994) proposed that Lake Michigan Lobe diamicton units systematically vary in clay mineralogy, as demonstrated by the 7- A/10-A ratio, depending on the bedrock and pre-existing drift each advance incorporated into its diamictons. Shale is rich in 10-A clay, illite, whereas pre-existing lacustrine deposits and other drift lithologies are low in 10-A clay. Glacial erosion of Sangamon sa-prolite, which is high in kaolinite (Monaghan, 1994), increased the 7-A clay content of the Lake Michigan Lobe diamicton. Therefore variation between units depends in part on the source material being overridden. Three diamicton units associated with the Lake Michigan Lobe were identified by Monaghan and Larson (1986) based of comparison of the 7- A/10-A mean peak height ratio for each unit. All units are exposed at a Lake Michigan bluff, near Glenn Shores, Michigan. Two units were traced eastward by analysis of surficial samples and by observation of gravel pit exposures. The oldest unit, the Glenn Shores Till, has a 7-A/10-A mean peak height ratio of 1.22 ±0.31 and was only observed at the bluff. The ± value refers to the first standard deviation. The overlying Ganges Till has a 7-A/10-A ratio of 0.85 ±0.18 at the bluff and is correlated with the lower diamicton unit in exposures west of the Outer Kalamazoo Moraine, which have a ratio of 0.83 ± 0.22 and with surficial exposures east of the moraine to the west branch of the Tekonsha Moraine, which have a 7-A/10-A ratio of 0.83 ±0.41. The Saugatuck Till is the youngest of the three units and has a 7-A/10-A ratio of 0.58 ±0.13 at the bluff and 0.52 ±0.21 in gravel pit exposures west of the Outer Kalamazoo Moraine. Monaghan and Larson (1986) inferred that the retreating glacier that deposited the Saugatuck Till 35 also formed the Kalamazoo, Valparasio, and Lake Border Moraine Systems whose surficial diamicton have 7-A/10-A ratios of 0.61 ±0.25, 0.65 ±0.23, and 0.61 ±0.15 respectvely. Monaghan and Larson (1986) sampled Saginaw Lobe diamicton material from the Lansing Moraine in Eaton County to the Leonidas Drumlin Field in northeastern St. Joseph County. Two diamicton units were isolated using x-ray diffraction techniques. Samples were taken by a drill rig at depths up to 10 meters and with a hand auger to 2 to 3 meter depth. From borings in Eaton County, Monaghan and Larson (1986) identified the surficial Bedford Till and the underlying Fulton Till. The mean 7-A/10-A peak height rato of the Bedford till was 0.72 ±0.27. The Bedford Till in Eaton County is correlated with the surface diamicton of the Kalamazoo Moraine of the Saginaw Lobe, which has a mean 7-A/10-A peak height ratio of 0.75 ±0.31. The Bdford Till was not found south of the Kalamazoo Moraine. The Fulton Till underlies the Bedford either directly or is separated by a sand and gravel layer. The mean 7-A/10-A peak height ratio of the Fulton Till from Eaton County was 1.13 ±0.33. The Tekonsha Moraine of the Saginaw Lobe and the Leonidas drumlin field have mean 7-A/10-A peak height ratios of 1.12 ±0.42 and 1.28 ±0.70 respectively, indicating a similarity to the Fulton Till unt. Some samples collected by Monaghan and Larson (1986) were analyzed for qualitative clay content. The clay size fraction was mounted on porous ceramic plates and the fllowing treatments were performed before x-ray analysis: Mg solvation, glycerol solvation, K saturation and air dried then heated to 300 °C then 550 °C. The results determined the 36 presence of illite, kaolinite, and chlorite with minor amounts of vermiculite. Smectitie was not generally found. Rieck (1979) used the peak height ratio to differentiate between Saginaw and Erie Lobe surficial deposits east of the study in Jackson, Washtenaw, and Livingston Counties. The surficial till of the Kalamazoo Moraine, of the Saginaw Lobe had 7-A/10-A peak height ratios greater than 0.91. Erie Lobe diamictons at the Mississinewa Moraine had a 7-A/10- A peak height ratio less than 0.91. By using the Student's t test, the mean 7- A/10-A ratios for each lobe are signifcantly different at the 0.001 level (Rieck, 1979). The interlobate boundary delineated by Rieck's 7-A/10-A ratio data agreed with the interpretations of Leverett (1915) and Kneller (1964). Rieck further concluded that this x-ray diffraction technique could be used on a regional scale to differentiate surficial drift based on data pooled by Mahjoory (1971), Rieck (1976), and Laurin (1976). These pooled data from south-central and southeastern Michigan shows that diamicton northwest of the interlobate boundary has 7-A/10-A peak height ratios greater than 0.91, and less than 0.90 southeast of the boundary. Lovan (1977) also used the 7-A/10-A ratios to interpret the surficial western interlobate boundary of the Saginaw Lobe and the Lake Michigan Lobe in Kalamazo and Calhoun Counties. The interlobate boundary was interpreted to include the deposits of the western branch of the Tekonsha Moraine as Lake Michigan Lobe drift and the eastern branch as Saginaw Lobe drift. This boundary position is just east of Shah's (1971) interpretation that is based on weak morainal ridges; and concurs with the boundaries of Monaghan and Larson (1986), but far to the east of the 37 boundary determined by Dodson (1993). Lovan (1977) found that the Saginaw Lobe deposits had 7-A/10-A peak height ratios of 0.880 ±0.119, which differed significantly from the Lake Michigan Lobe ratios of 0.766 ±0.125. Lovan's (1977) mean 7-A/10-A peak height ratio for surficial Saginaw Lobe drift in southwest Michigan is lower than the value determined by Monaghan and Larson (1986) in the same area. CHAPTER ill
RESULTS
X-Ray Diffraction and Textural Analysis Results
The borings from Sturgis contains six significantly different, carbonate rich subsurface diamicton units and one diamicton unit that is depleted in calcite (Plate I). The surface diamicton unit was not analyzed for this study. Not all units are continuous between adjacent boring locations. Diamicton units were differentiated from one another based on the 7-A/10-A peak height ratios and textural analysis.
Unit 1 and Unit 2
Unit 1 overlies the Coldwater Shale or lacustrine deposits above the shale with the base of Unit 1 at depths between 217 feet and 274 feet below ground surface. Because of direct communication with the gray shale, the lithology of diamicton Unit 1 is shale rich in all grain sizes and gray to dark gray ( wet SY 5/1 to 2.5 Y 4/1) in color. Found in all the four borings, the mean 7-A /10-A peak height ratio for Unit 1 is 0.446 ± 0.069. (The ± value refers to the first standard deviation.) See Figure 9 for example x-ray diffraction results. The student t-test is used to determine if two groups of mean 7-A /10-A peak height ratios are statistically similar or significantly different from one another at a specified confidence interval. The calculation made, in this study, is at the 95% confidence interval unless
38 39
UNIT I
Figure 9. Example of Unit 1 Diffractograms and 7-A /10-A Peak Height Ratio Values. 40 otherwise noted. The mean 7-A /10-A peak height ratios fr Unit 1 in each
boring, are statistcally similar to each of the other borings {Table 3). In
general the texture of Unit 1 is a sandy clay loam to loam with an average
of 40.5% sand, 32.7% silt, and 26.8% clay (Figure 10).
At W-43, Unit 1 is at least 2 feet thick, but may be thicker because
samples below 219 fet were not recovered. The observed base of the unit is at 219 feet below land surface, where it is overlain by Unit 2 and
lacustrine deposits. At W-45, the lowest materials are Unit 1, a mixture of
Units 1 and 2, and lacustrine deposits, interbedded between 232 and 245 feet below the surface; units are between 1 and 4 feet thick. Deformation of
Units 1 and 2 is obvious from the distinct interbedding of 1 to 2 cm thick
bands of the gray and olive brown lithologies and this mix is considered
Unit 2. Tis sequence is overlain by 22 feet of gray lacustrine deposits. The
base of Unit 1 in W-44 is at 274 fet below ground surface and is observed to be 3 feet thick. No recovery was obtained below 274 feet. Unit 1 is
overlain by 38 feet of lacustrine deposits. At W-46, Unit 1 has two layers.
The base of the lower unit is at 260 feet below the surface and is 18.5 feet thick. The upper layer of Unit 1 is 2 feet thick, found within Unit 2, and lies 1.5 feet above the top of the lower Unit 1.
Unit 2 is a non-continuous yellowish brown, olive brown, to light olive brown ( wet l0YR 5/8 to 5/4 and 2.SY 4/2, 5/4, 5/6 ) diamicton unit that overlies or is interbedded with Unit 1. Unlike Unit 1, the lithology
and clay mineralogy of Unit 2 does not suggest as much communication with the gray Coldwater Shale but the unit dos contain iron concretions. 41 Table 3 A Student t-test Comparing 7- /10-A Ratios Between Borings, #1
Boring and Unit t-value UA A
W-45 Unit 4 2.5358 0.09321 0.0288 W-44 Unit 4
W-43 Unit 2 12.0753 0.8243 0.1788 W-46 Unit 2 2.4126 0.1687 0.1375 W-45 Unit 2(a) 2.9579 0.2839 0.0412 W-43 Unit 2
W-45 Unit 2b 2.2338 0.1812 0.6547 W-45 Unit 2a
W-43 Unit 1 3.5845 .2325 0.0255 W-46 Unit 1 3.0262 0.1436 0.0415 W-44 Unit 1 4.2300 0.2937 0.0283 W-45 Unit 1 3.4180 0.2814 0.0387 W-43 Unit 1 3.5845 0.2325 0.0255 W-46 Unit 1 9.4810 0.5771 0.0205 W-45 Unit 1 4.0567 0.2902 0.0210 W-44 Unit 1 Notes: All Calculations Made at the 95% Confidence Interval Unless Noted ,. - Calculation Made at the 98% Confidence Interval 42 Clay
Sand Silt 20 40 60 80 UNITl* W-43UNIT2G) W-45UNIT2. W-45 UNIT2 Q W-46 UNIT2 e
U.S. Dept. of Agriculture Soil Textures
c Clay sci Sandy clay loam si Silt sicl Silty clay loam s Sand d Clay loam I Loam sil Silt loam sc Sandy clay sl Sandy loam sic Silty clay Is Loamy sand
Figure 10. Textural Resultsof Unit 1 and Unit 2. 43 The sand fraction of Unit 2 is dominated by quartz and feldspar with minor amounts of shale. The mean 7-A /10-A peak height ratio for Unit 2 is 0.657 ± .151 (Figure 11). In general the texture of Unit 2 is dominantly sandy loam to loam with an average of 57.2% sand, 25.8% silt, and 17.0% clay (Figure 10). At W-43 Unit 2 is 1.5 feet thick and directly overlies Unit 1, see Plate 1. A lacustrine deposit 56 feet thick overlies Unit 2 at W-43. At W-45 Unit 2 is composed of two subunits, a lower (Unit 2a) and an upper (Unit 2b). Unit 2a is a non-homogeneous interbedded mix of gray and brown diamicton. The texture of Unit 2a is a silt loam with 22.4% sand, 57.5% silt, and 20.1% clay. The texture Unit 2a at W-45 differs from the typical sand loam of Unit 2. The mean 7-A /10-A peak height ratio for Unit 2a at W-45 is 0.712 ±0.182. This is statistically similar to Unit 2 at W-43 and W-46 thus Unit 2a is considered Unit 2 (Table 3). Unit 2b at W-45 is a 3.5 feet thick brown diamicton overlying 21 feet of lacustrine deposits that in turn overlie Unit 2a. The mean 7-A /10-A peak height ratio of the Unit 2b is 1.367 ± 0.106 which is significantly different from the lower Unit 2a. Unit 2 is not found at W-44, where 38 feet of lacustrine sediment overlies Unit 1 see Plate 1. At W-46, Unit 2 is 7.5 feet thick but has an interbed of Unit 1. Unit 2 at W-46, above and below the interbedded Unit 1, has statistically similar mean 7-A /10-A peak height ratios as Unit 2 at W-43 and the Unit 2a at W-45. Units 1 and 2 differ from one another lithologicaly, texturally, and in clay mineralogy as indicated by the 7-A/10-A ratios. The lithology of Unit 1 is dominated by gray shale whereas the lithology of Unit 2 is 44
UT2
Figure 11. Examples of Unit 2 Diffractograms and 7-A /10-A Peak Height Ratos Values. 45 characterized by quartz and feldspar with iron concretions. Not including Unit 2b at W-45, the collective mean 7-A /10-A peak height ratios of Units 1 and 2 are significantly different from one another, see Appendix H. At W-43 the mean 7-A /10-A peak height ratios of Units 1 and 2 are significantly different only to the 90% confidence interval because of the limited degrees of freedom, 1.0313. At W-46 and W-45 however, the mean 7A /lOA peak height ratios of Units 1 and 2 are significantly different at the 95% confidence interval. In general, Unit 1 has greater than 20% clay and less than 52% sand (sandy clay loam), contrasting with Unit 2 that typically contains less than 20% clay and greater than 52% sand (sand loam) (Figure 10).
Unit 3. Unit 4 and Units
Seventy-eight to 109 feet of brown outwash sand and gravel, Unit 3, overlie Units 1, 2, and the associated lacustrine deposits at all borings in the study area, see Plate 1. Unit 4 is a dark grayish brown (wet 2.5 Y 4/2) sandy loam to loam diamicton (Figure. 12) overlying the thick outwash unit. Unit 4 is found only at W-45 and W-44. At W-45, Unit 4 is 6 feet thick, with its base at 121 base below land surface, reaching a thickness of 29 feet at W-44 where the base is at 145 feet. The mean 7-A /10-A peak height ratio for Unit 4 is 1.059 ±0.090 (Figure 13). Between W-45 & 44 Unit 4, the mean 7-A /10-A peak height ratios are statistically similar to one another (Table 3). Unit 5 directly overlies Unit 4 except at W-46 where Unit 4 is absent. Both Units 4 and 5 are absent in W-43. The texture of Unit 5 ranges from a 46 silty loam to a loam to a clay loam. Unit 5 can be separated into a dark brownsh gray (wet 2.5 Y 4/2) unweathered subunit, Unit Sa, and a light olive brown (wet 2.5 Y 5/3) weathered subunit, Unit Sb. Unit Sa has a mean 7 A /lOA peak height ratio of 0.810 ± 0.072 in contrast to Unit 5 which has a mean of 0.524 ±0.157 (Figure 14). The mean 7-A /10-A peak height ratios for the two subunits are significantly diferent (Table 4). Unit 5b is statistically similar in W-46 and W-45 not at the 95% confidence interval but at 98%. Unit Sa is statstically similar in W-46, W-44, and W - 45. At W-45, 5 feet of Unit Sa lies directly upon Unit 4. The base of the 3 fot thick Unt 5b at W-45, is 88 feet below surface and is separated by Unit Sa by 22 feet of sand and gravel. At W-44 the base of Unit Sa is at 116 feet below land surface directly upon Unit 4. Unit Sa is 17 feet thick but is interbedded with thee lacustrine deposits 1 to 2 feet thick and is overlain by a 19 fot thick lacustrine deposit. At W-46 Unit Sa is interbedded with three layers of Unt 5b and three sand and gravel units. The interbedded units are 1 to 3.5 feet thick. At W-46, the base of Unt 5 (a and b combined) is at 124 feet below the surface and is 31 feet thick.
Unit6
A thin discontinuous unit, recognized by lack of reaction with hydrochloric acid, overlies Unit 5. This carbonate poor unt is thus referred to as the leached unit, Unit 6, and is found in all the borings except W-45. At W-43 about a fist-full of a sample was recovered between 82 and 84 feet below the surface. Not enough sample was recovered to do a 47
Clay
Sand 20 Silt 40 60 80
UNIT4 _A UNIT 5 ■ UNIT 5b.
U.S. Dept. of Agriculture Soil Textures
C Clay sci Sandy clay loam si Silt sic! Silty clay loam Sand cl Clay loam Loam S11 Silt loam Sandy clay sl Sandy loam sic Silty clay Is Loamy sand
Figure 12. Textural Results of Unit 4 and Unit 5. 48
Figure 13. Examples of Unit 4 Diffractograms and 7-A/10-A Peak Height Ratio Values. 49
UNIT 5
UNIT Sb
Figure 14. Examplesof Unit 5 Diffractograms and 7-A/10-A Peak Height Ratio Values. 50 Table 4
Student t-test Comparing 7-A/10-A Ratos Between Borings, #2
Boring and Unit t-value UA A
W-44 Unit 5 2.1693 0.0620 0.0237 W-45 Unit 5 2.1571 0.0657 0.0128 W-46 Unit 5 2.0701 0.0637 0.0109 W-44 Unit 5
W-46 Unit Sb 2.1892 0.1355 0.1501 2.6984* 0.1670* 0.1501 W-45 Unit Sb
Notes: All Calculations Made at the 95% Confidence Interval Unless Noted , - Calculation Made at the 98% Conidence Interval
textural analysis without losing the sample and x-ray diffraction produced no diffraction pattern. At W-44, in which the base of the dark grayish brown (wet 2.SY 4/2) diamicton is at 85 feet below the land surface, Unit 6 is 4 feet thick and overlies lacustrine deposits. The texture of the leached unit at W-44 is loamy and x-ray diffraction produced a tall, broad 14-A peak and a short 7-A peak. No 10-A peaks were produced. At W-46 the dark yellowish brown (wet l0YR 4/6) leached unit is only 1 feet thick overlying Unit Sb. With its base at 93 feet below the surface, Unit 6 is overlain by 5 feet of red and brown oxidized silty sand. The texture of the leached unit at W-46 is a clay loam and the x-ray diffraction patterns 51 produced dull 7-A and 10-A peaks with a low mean 7-A/10-A peak height ratio 0.407. The possibility exists that Unit 6 is actually altered Unit 5.
Unit Z and Unit 8
Unit 7, informally called the Gray Marker, is a light olive brown to dark grayish brown (2.5 Y 5/3 to 5/4 to 4/2) diamicton, 4 to 10 feet thick unit continuous between all four borings. The sand fraction contains more dark meta-sediments than adjacent units that are quartz and feldspar rich. The texture of the Unit 7 is loamy with an average of 38.6% sand, 43.0% silt, and 18.4% clay; in general there is greater than 40% silt, and less than 45% sand (Figure 15). The mean 7-A /10-A peak height ratio is 0.865 ±0.090 (Figure 16). The mean 7-A /10-A peak height ratio of Unit 7, between all borings, is statistically similar to one another. Unit 8 directly overlies Unit 7 at all locations except W-45 where Unit 8 is missing and Unit 7 is overlain by sand (Table 5). The gray to grayish brown (wet 2.5YR 5/1 to 5/2) Unit 8, the uppermost subsurface diamicton, is between 5 and 32 feet thick. Only the upper 4 feet of Unit 8 at W-46 has weathered to light yellowish brown and light olive brown (wet 10 YR 5/4, 6/6 and 2.5 Y 5/4) and is referred to as Unit 8b. The texture of the Fulton ranges between sandy clay loam and sandy loam to loam and contains generally less than 40% silt and greater than 45% sand (Figure 15). Unit 8 has an average of 49.8% sand, 29.5% silt, and 18.4% clay. The mean 7-A /10-A peak height ratio for the unweathered Unit 8 is 1.195 ±0.189 (Figure 17). The mean 7-A /10-A peak height ratio for the Unit 8 at each location is statistically similar to Unit 8 52
Clay
Sand Silt 20 40 60 80 UNIT78 UNITS {;J
U.S. Dept. of Agclture Soil Texure
C Qy s Sady cy loa s Sit sd Sity clay lo s Sd c Cy loa I Loa sl Sit loam s Sdy cy s Sdy loa sc Sit cy I Loay sd
Fige 15. Textural Results of Unit 7 and Unit 8. 53
UNIT7
! ' 1 ·• • . ! l I : l - : ' j, . ! : ; ; . . ..: ' --r----1 -1-0--:-
Figure 16. Examples of Unit 7 Diffractograms and 7-A/10-A Peak Height Ratio Values. 54 Table 5
Student t-test Comparing 7-A/10-A Ratios Between Borings, #3
Boring and Unit t-value UA
W-46 Unit 8 2.0320 0.1311 0.0418 W-44 Unit 8 2.0700 0.1137 0.1082 W-43 Unit 8 2.0676 0.0890 0.0664 W-46 Unit 8
W-43 Unit 7 2.2483 0.0851 0.0205 W-46 Unit 7 2.4035 0.1178 0.0287 W-44 Unit 7 2.2674 0.1471 0.0783 W-45 Unit 7 2.3132 0.1316 0.0865 W-43 Unit 7 2.2483 0.0850 0.0205 W-46 Unit 7 2.5437 0.1254 0.1070 W-45 Unit 7 at all other locations in the study area. Unit 8b at W-46 has a mean 7-A /10-A peak height ratio of 0.728 ±0.659, significantly different than then underlying unweathered unit, and has sandier texture. The texture of Unit 8b was analyzed for only one sample resulting in 63.8% sand, 25.8% silt, and 10.4% clay. At each boring where both Units 7 and 8 are present, the mean 7-A /10-A peak height ratios of each unit are significantly different (Table 5). In 55
UNITS
UNIT8b
Figure 17. Examples of Unit 8 Diffractograms and 7-A/10-A Peak Height Ratio Values. 56 general Unit 8 is sandier than Unit 7, and Unit 7 is richer in silt. The sand lithologies also differ. The sand of Unit 7 is darker and contains considerable amounts of dark meta-sediments, whereas quartz and feldspar predominates in the lighter colored sands of Unit 8. Sand and gravel outwash units 42 to 70 fet thick were deposited on top of Unit 8 or Unit 7, and is considered the Sturgis Moraine outwash fan.
Correlationof Unit8 to the Fulton Tillof Monaghan and Larson (1986)
From analyses of samples taken from borings drilled in Eaton County, Monaghan and Larson (1986) found that the Fulton Till, the lower diamicton described in the study, had a 7-A/10-A peak height ratio of 1.13 ±0.33. The texture of the Fulton in the borings averaged 43% sand, 44% silt, and 13% clay. Samples from the Tekonsha Moraine and the Leonidas drumlin field yielded ratios of 1.12 ± 0.42 and 1.28 ±0.70 respectively. From student-t tests based on this data, Monahan and Larson (1986) concluded that the Leonidas Drumlin Field and the east branch of the Tekonsha Moraine contain Fulton Till. From borings in Sturgis analyzed in this study, the subsurface diamicton unit directly below the Sturgis Moraine outwash fan, Unit 8, has a mean 7-A/10-A peak height ratio of 1.19 ±0.19. Student-t testing of the 7-A/10-A ratios of Unit 8 versus the ratios of the Leonidas Drumlin Field, Tekonsha Moraine, and the Fulton Unit in Eaton County shows that the units are statistically similar. Thus it can b assumed that Unit 8 is the Fulton Till. 57 Correlationto UnpublishedData
A boring was made on the Sturgis Moraine on the west side of the St. Joseph County Scott in 1997 (Kindzerski, unpublished data). The boring made in a gravel pit, where fifty feet of sandy lacustrine sediment previously removed, is located on the east side of the moraine and sand was found to 60 feetbelow the gravel pit floor. A thin diamicton unit was found from 60 to 65 feet on top of a thick sand unit. Below the sand another diamicton unit was found from 152 to 190 feet below ground surface. The thin upper unit has a mean 7-A/10-A peak height of 0.73 ± 0.03, and the lower diamicton has a ratio of 0.58 ± 0.013. Statistically, the upper and lower units are similar, but this may misleading because of the limited degrees of freedom, 1.193. On the other hand, the upper diamicton unit is statistically similar to the Saginaw Lobe Bedford Till investigated by Monaghan and Larson (1986). The upper unit may be correlated with the surface diamicton overlying the Sturgis Moraine outwash fan. Flemming (1997) has observed that the diamicton associated with the Shipshewana and the Newbury Moraines to be sandier than the Middlebury Moraine. This is similar to the relationship this study provides between Unit 7 and 8. CHAPTER IV
DISCUSSION
Rieck (1979) concluded that the 7-A/10-A ratio of diamicton units was controlled by nearby bedrock contributions, regional bedrock composition, older drift units, and weathering during interglacials. These factors account for variability of units at one location and variability of a single unit along the flow path of a glacier. The degree of weathering of the diamicton before incorporation in the glacier or after deposition also affects variations in clay mineralogy. Monaghan (1994) suggested that differences in mean 7-A/10-A peak height ratios of Lake Michigan Lobe diamicton units were caused by differential erosion of two distinct source beds: shale bedrock and pre-existing drift. Diamicton units high in 10-A clay (illite) were derived from erosion of shale. Units depleted in illite were derived from pre-existing drift, especially lacustrine deposits. Rieck (1979) proposed an interlobate boundary in southeastern Michigan based on differences in the 7-A/10-A peak height ratios. The Saginaw Lobe, which overrode Upper Mississippian and Pennsylvanian bedrock, has a high 7-A/10-A ratio. The Huron-Erie Lobe advanced over the Coldwater Shale resulting in a low 7-A/10-A ratio. Weathering of illite and chlorite eventually creates expandable clay minerals. Chlorite can be altered to a mixed vermiculite-chlorite clay and finally to a nonexpandable 14-A vermiculite. Illite also alters to vermiculite, but can further alter to montmorillonite. Vermiculite may
58 59 expand to a 17-A clay. Kaolinite has been observed to remain unaltered by weathering and is a weathering product. Alteration of chlorite, which reduces the 7-A peak, happens before alteration of illite. Thus weathering initially reduces the 7-A/10-A ratio because of the readily alterable chlorite until the point at which illite begins to alter and the 10-A peak weakens. (Willman et al., 1966). These weathering patterns may account for the differences in 7-A/10-A ratios between borings but this study did not qualitatively determine clay types. Further study should include investigation of some samples mounted on porous ceramic plates with the following procedures performed before each x-ray analysis: glycerol solvation, Mg saturation, and K saturation and air dried, heated to 300 °C, and heated to 550 °C. This method is used to determine the qualitative clay mineral content.
Unit 1 and Unit 2
Unit 1 directly overlies the Coldwater Shale whose clay mineralogy is dominated by illite. Erosion of the shale is reflected in the low mean 7- A/10-A peak height ratio. Within Unit 2, the 10-A peak is less intense than in Unit1. Further research must be performed to determine the clay mineral differences between Units 1 and 2 that account for the differences in 7-A/10-A peak height ratios. Differences in source material erosion are reflected in the texture, and it is found that Unit 1 contains a higher clay content than Unit 2. At W-45 Unit 2b, the 10-A peak height has decreased with respect to the rest of Unit 2 and the color is lighter. Weathering of Unit 2b may account for these differences. 60 Unit 4 and Unit S
Within Unit 4, the 7-A and 10-A peak heights are approximately equal, although the 7-A peak heights of Unit Sa are generally slightly less intense than in Unit 4. There is no distinguishable textural relationship between Units 4 and Sa. Unit S contains weathered subunits (Unit Sb) at two of three locations. The 7-A/10-A ratio of Units Sb is less than the rest of Unit S and both peaks are less intense. Similar weathering observations have been made by Willman et al. (1966) and Curry et al. (1994) in Illinois and by Bhattacharya (1962) in Indiana with respect to the 7-A/10-A ratos.
Unit 6
The clay mineralogy of the leached unit, Unit 6, varies drastically. At W-46 the leached unit produced measurable 7-A and 10-A peaks but of low intensity and low rato. These hypothesized effects of weathering are similar to those of Unit Sb and by Willman et al. (1966) and Curry et al. (1994) in Illinois and by Bhattacharya (1962) in Indiana. Weathering was probably not as significant at W-46 than at other locations. At W-44 the diffractogram was dominated by a tall and broad 14-A peak and a short, sharp 7-A peak. At W-43 the leached unit produced no peaks indicating that no true clay exists, suggesting that clay minerals have been completely destroyed leaving only iron and aluminum oxides. The Sangamon Iterglacal may have weathered the day of Unt 6. It has not been determined if Unit 6 is actually weathered Unit S or a deposit of a different advance. 61 Unit 7 and Unit 8
Unit 7 has a lower mean 7-A/10-A peak height ratio than Unit 8 (the Fulton Till) which overlies it. Within both units, the dull shapes of the 10-A peaks are similar. The 10-A peaks of Unit 8 and Unit 7 are not as sharp as units 1, 2a, 4, and Sa. Further resecrch must be conducted to determine the mineralogical difference that accounts for the mean peak height ratios to differ. Rieck (1979) observed similar differences between diamictons from known sources and attributed these differences to the bedrock which was eroded. Differences in parent material is obvious from the texture and from the color of the fine sands associated with the unit. The fine sands of the Unit 7 have a light brownish gray (2.SY 6/2) color while the Fulton is pale yellow (2.SY 7/3). The coarse sand and gravel of Unit 7 is dominated by mainly by meta-sediments and siltstone with lesser amounts of chert, quartz, and fldspar. This differs from Unit 8 which is dominated by igneous rocks, siltstone, chert, iron concretions, quartz, and feldspar. Silt is more abundant in Unit 7 than Unit 8 which is more sand dominated. The dark sand lithology of Unit 7 corresponds to the sand lithology found in Huron-Erie Lobe deposits whereas the sand lithology of Unit 8 is what is expected of Saginaw Lobe deposits (Kehew, 1997). CHAPTER V
CONCLUSIONS
Seven distinctly different diamicton units were identified below the surface diamicton in four continuously sampled cores from Sturgis, Michigan. Differentiation is based on clay mineralogy using x-ray diffraction techniques and textural analysis. To better quantify the clay mineralogy data, the 7-A peak is divided by the 10-A peak resulting in a mean 7-A/10-A peak height ratio for each unit. This measure is useful because it relates the content of illite (10-A) to that of chlorite and kaolinite (7-A). The mean ratios of each diamicton unit were compared using the student-t test to determine if populations were similar or significantly different at the 95% confidence interval. The textures of some diamicton units contrasts enough to distinguish between units. The differences between diamicton units can be accounted for by regional bedrock subcrops and other material the ice incorporated, such as older drift and weathered surficial material. Two distinctly different diamicton units are deposited at the base of the drift section. Unit 1 is a gray to dark gray continuous unit, which lies directly upon the bedrock or upon lacustrine deposits overlying bedrock. The mean 7-A/10-A peak height ratio of Unit 1 is 0.446 ± 0.069 with an average texture of 40% sand, 33% silt, and 27% clay. Unit 2 is a yellowish brown diamicton that is non-continuous between borings and is either overlies or is incorporated into Unit 1. The 7-A/10-A ratio for Unit 2, 0.657 62 63
± 0.151, differs significantly from Unit 1. Unit 2 is also sandier with an average texture of 57% sand, 26% silt, and 17% clay. Units 1 and 2 are separated from overlying units by lacustrine sediment and Unit 3, a thick outwash deposit. The dark grayish brown Unit 4 is found only at two of four locations overlying Unit 3. The mean peak height ratio for Unit 4 is 1.059 ± 0.090 with an average texture of 51% sand, 32% silt, and 17% clay. Unit 5 lies discontinuously over Unit 4 or Unit 3 where Unit 4 is not present. The texture of Unit 5 is richer in fines with an average of 42% sand, 37% silt, and 21% clay and the 7-A/10-A ratio of 0.810 ±0.072 is significantly different from that of Unit 4. Unit 5 contains some weathered horizons, referred to as Unit Sb, where the ratio is reduced to 0.524 ± 0.157 and the variation of texture is similar to Unit Sa. Unit 5 is overlain by the leached unit, Unit 6. The leached diamicton Unit 6 is discontinuous and has been weathered to varying degrees between borings. Common throughout Unit 6 is the lack of reaction when exposed to HCl. This suggests leaching of carbonates occurred during weathering. At one location weathering was not extreme and a low 7-A/10-A ratio is produced by rounded, short peaks.
At an adjacent only a 14-A and a 7-A kaolinite peak were produced. At the final boring where Unit 6 is found, no peaks were produced. Thus the Unit 6 demonstrates varying degrees of weathering as a result of differing locations in the weathering profile. Because of the extensive weathering found within Unit 6, Unit 6 may have weathered during the Sangamon Interglacial. 64 Unit 7 is a continuous diamicton unit found between all the borings in Sturgis. Unit 7 is informally referred to as the Gray Marker because of dark meta-sediments found in the drift and the dark tones of the silt and clay. The mean 7-A/10-A peak height ratio for the unit is 0.865 ± 0.090. The texture has an average of 39% sand, 43% silt, and 18% clay. The color and texture of the Gray Marker can be traced to at least the Middlebury Moraine in Elkhart and LaGrange Counties, Indiana (Nicks, 1997). The dark meta-sediments in the sand fraction suggests Unit 7 may be of Huron-Erie Lobe origin (Kehew, 1997). Unit 8 is discontinuous and lies directly overlies Unit 7. Unit 8 has a 7-A/10-A peak height ratio of 0.728 ± 0.066 and the color is lighter in tone than Unit 7. Unit 8 has an average of 49.8% sand, 29.5% silt, and 18.4% clay that is obviously different from Unit 7. Based on clay mineralogy, Unit 8 is similar to the Fulton Till found in Eaton, Calhoun, and Kalamazoo Counties (Monaghan and Larson, 1986). Unit 8 has also been shown to be similar to diamicton associated with the Tekonsha Moraine and the Leonidas Drumlin Field. This study shows that the deposits forming the Sturgis Moraine is similar to Unit 8 and unpublished observations find the diamicton unit extends to LaGrange County, Indiana (Flemming, 1997). There Unit 8, the Fulton Till, is associated with the Newbury Moraine and the Shipshewana Moraine which is a push moraine (Flemming, 1997). A surface diamicton advanced after deposition of the Fulton and caps drift associated with the Fulton advance from the Sturgis to the Shipshewana Moraines. 65 During the maximum advance of the Wisconsin Episode, the Saginaw Lobe formed the Iroquois Moraine near the Indiana and Illinois boarder. From this position the ice retreated and stalled forming the Maxinkuckee and New Paris Moraines. Either the ice retreated further and stalled or readvanced and stalled to form the Middlebury Moraine before further retreat. Based on this study, the ice, which deposited the Fulton Till, Unit 8, advanced to the Newbury and Shipshewana Moraines in LaGrange County, Indiana just north of the Middlebury Moraine. During this time the Leonidas drumlin field may have formed based on interpreted tunnel valleys (Nicks, 1997). After this maximum advance, the Sturgis and Tekonsha Moraines were formed. At approximately 15,500 years before present, the Erie Interstade approached and the Fulton ice retreated. Following the interstade, Saginaw Lobe ice advanced depositing the Bedfrd Unit and formed the Kalamazoo Moraine (Monaghan and Larson, 1986). At some time, a thin surface diamicton was deposited from the Sturgis Moraine to the Shipshewana Moraine. This study supports previous works suggesting tat diamicton units can be differentiated by clay mineralogy based on the 7-A/10-A peak height ratio. The ratio also allows for diamicton units to b compared between locations on a regional scale. Diamicton units also may vary texturally which may also aid in differentiatng units at a local scale. Texture tends to vary more than the 7-A/10-A peak height ratios on a regional scale. The method followed by this study has been shown to be successful in identifying diamicton units in Southern Michigan (Reick et al., 1979; Monaghan and Larson, 1986). Appendix A 7-A/10-A Rato Statstcs
66 67
7-A/10-A Ratio Statistics
Average 7-A110-A Standard Boring and Unit Ratio Deviation # W-46 Unit 8b 0.7282 0.0659 4 W-46 Unit 8 1.1865 0.1688 19 W-44 Unit 8 1.2283 0.2308 20 W-43 Unit 8 1.1201 0.0496 7 Unit 8 Total 1.1946 0.1887 46
W-46 Unit 7 0.8931 0.0611 12 W-44 Unit 7 0.8644 0.1121 6 W-45 Unit 7 0.7861 0.1029 5 W-43 Unit 7 0.8726 0.0885 7 Unit 7 Total 0.8648 0.0899 30
W-46 Unit Sb 0.4837 0.1615 11 W-46 Unit Sa 0.8131 0.0797 12 W-44 Unit 5 0.8022 0.0764 12 W-45 Unit Sb 0.6338 0.0764 4 W-45 Unit Sa 0.8259 0.0447 5 Unit Sb Total 0.5237 0.1568 15 Unit S(a) Total 0.8102 0.0721 29
W-45 Unit 4 1.0338 0.0636 4 W-44 Unit 4 1.0626 0.0940 26 Unit 4 Total 1.0587 0.0902 30
W-46 Unit 2 0.57425 0.0341 7 W-45 Unit 2b 1.36650 0.1057 6 W-45 Unit 2a 0.7118 0.1818 7 W-43 Unit 2 0.7530 0.0948 2 Unit 2(a) Total 0.6568 0.1513 16 68 7-A/10-A Ratio Statistics (Cont.)
Average Diamict Unit or Feature 7-A/10-A Standard Ratio Deviation # 46 Unit 1 0.4512 0.0533 5 45 Unit 1 0.4307 0.0792 3 44 Unit 1 0.4097 0.0711 3 43 Unit 1 0.4767 0.1045 3 Unit 1 Total 0.4455 0.0687 15
W-46 Unit 6 0.4069 0.0843 2 W-44 Unit 6 NA 5 W-43 Unit 6 NA 1 Bedford Till*+ 0.72 0.27 11 Fulton Till*+ 1.13 0.33 19 Tekonsha Moraine*+ 1.12 0.42 9 Kalamazoo Moraine*+ 0.75 0.31 17 Leonidas Drumlin Feild*+ 1.28 0.70 5 Saugatuck Till*A 0.58 0.13 25 Sturgis-Kalamazoo 0.61 0.25 14 System*A Sturgis Moraine, upper 0.73 0.03 2 unit**A Sturgis Moraine, lower 0.58 0.013 4 unit**A
Note:* Data aquired by Monaghan and Larson (1986) ** Data aquired by Kindzerski (1997) + Saginaw Lobe Landformor Diamict Lake Michigan Lobe Landform or Diamict Appendix B Textural Analysis Results
69 70 Textural Analysis Results
Boring and Unit % Sand % Silt %Clar n W-46 Unit 8b 63.8 25.8 10.4 1 W-46 Unit 8 47.9 ±18.0 27.6±5.2 17.7±4.4 6 W-46 Unit 7 42.9±8.7 38.9 ± 8.2 18.2± 1.4 4 W-46 Unit 6 34.0 25.1 40.6 1 W-46 Unit Sb 39.2±15.3 35.8 ±.5.9 25.1 ±7.7 4 W-46 Unit Sa 49.1 ±8.2 33.1± 3.1 17.7±6.5 2 W-46 Unit 2 57.2±3.0 25.8±2.3 17.0±2.0 4 W-46 Unit 1 46.7±3.8 29.7±0.8 23.7±4.2 4
W-44 Unit 8 49.0±6.7 32.9±4.3 18.1 ± 2.9 7 W-44 Unit 7 33.7±4.9 47.8±5.7 18.4± 1.2 3 W-44 Unit 6 (upper 3') 27.1± 0.6 49.9 ± 0.7 23.0± 1.8 3 W-44 Unit 6 (lower l') 41.0± 0.8 38.6 ± 0.2 20.5±1.0 2 W-44 Unit 6 Total 32.7±7.6 45.4 ± 6.3 22.0±1.9 5 W-44 Unit 5 32.0± 9.4 42.7±7.1 25.4 ±3.4 5 W-44 Unit 4 47.8±6.7 33.6±3.5 18.6 ±5.8 7 W-44 Unit 1 28.0±3.7 38.9 ±3.0 33.2 ±0.6 2
W-45 Unit 7 32.6±2.7 45.3±2.8 22.1 ±5.5 3 W-45 Unit Sb 44.3± 12.4 30.8 ±5.6 24.9 ±6.8 3 W-45 Unit Sa 49.6±4.3 32.6 ± 3.4 17.8 ±2.6 3 W-45 Unit 4 58.7±5.9 28.0± 2.8 13.5 ±3.2 3 W-45 Unit 2b 53.7±5.8 30.5 ±4.8 15.8 ±2.9 5 W-45 Unit 2a 25.7±4.9 56.5 ±2.6 17.8 ±2.3 3 W-45 Unit 1 38.4 ±5.4 36.0±3.0 25.7±2.4 2
W-43 Unit 8 54.0±2.7 26.1 ± 1.3 19.9 ±3.7 4 W-43 Unit 7 42.4± 7.0 41.8±3.6 15.9±4.2 4 W-43 Unit 2 17.5± 2.1 59.1± 1.2 23.5±0.3 2 W-43 Unit 1 41.9± 10.9 30.7±4.0 27.4 ±7.3 3 71 Textural Analysis Results (Cont.)
Unit % Sand % Silt %Clay n Unit 8 49.8± 11.2 29.5 ±5.0 18.4 ±3.6 17 Unit 7 38.6± 7.6 43.0± 6.1 18.4± 3.8 14 Unit 6 32.9 ± 6.9 42.0 ± 10.0 25.1 ±7.8 6 Unit Sb 41.7± 12.7 33.3 ± 6.6 25.0± 6.5 7 Unit Sa 42.6± 11.5 36.7± 6.8 20.7±5.8 10 Unit 4 51.0± 8.1 31.9± 4.1 17.1±5.6 10 Unit 2b @ W-45 53.7±5.8 30.5± 4.8 15.8±2.9 5 Unit 2a@ W-43, 46 57.2±3.0 25.8 ± 2.3 17.0±2.0 6 Unit 2@ 45 22.4± 5.7 57.5 ± 2.4 20.1 ±3.5 3 Unit 1 40.5±9.0 32.7±4.5 26.8±5.4 11 Note: The± Value Indicates the First Standard Deviation Appendix C W-46 Textural and X-Ray Diffraction Results
72 73 W-46 Textural and X-Ray Diffraction Results
Unit 8b
Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 43.5' 5.2% 15% 43.6% 25.8% 10.4% 0.8173 4 2 mid 45.5 5.7 13.6 43.6 . 0.7383 4 2 btm 46 0.6738 4 2 v.btm 46.5 6.1 15.3 39.0 0.6833 4 3 top
Unit 8a Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 48' 1.0750 4 3 2'btm 49.5 4.8% 10.9% 47.1% 23.0% 14.3% 0.9060 4 3 btm 50.5 1.0383 4 4 top 52 1.0285 4 4 mid 52.5 5.2 13.6 42.2 27.1 11.9 4 4 18"btm 53 0.8463 4 4 18"btm 54 1.0710 4 4 btm 55.5 1.2845 5 1 mid 57 1.3963 5 1 btm 58 4.1 13.7 38.9 26.8 16.5 1.3883 5 2 l'top 59 1.2418 5 2 2'btm 60.5 3.4 13.3 38.2 1.1773 5 2 btm 62.5 6.8 11.3 37.. 8 25.9 18.2 1.1308 5 3 1.5'top 4.6 14.6 42.5 1.1383 6 1 v.top 66 1.1673 6 1 btm 66.5 3.1 12.9 36.5 1.3660 6 2 top 66.5 3.0 6.4 29.7 37.8 23.1 1.1845 6 2 top #2 67 3.0 13.5 36.5 6 2 l'top 68.5 1.2808 6 2 l.5'btm 69 4.1 14.4 33.8 25.3 22.4 1.4293 6 2 l'btm 70 1.3930 6 2 v.btm 74 W-46 Textural and X-Ray Diffraction Results (Cont.) Unit 7 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 70.5' 0.8270 6 3 top 71 2.7% 9% 27.7% 43.8% 16.8% 0.8080 6 3 l'top 72.5 0.9213 6 3 mid 73.5 3.3 7.2 28.1 - 0.8590 6 3 btm 74 3.4 13.9 38.6 26.6 17.5 0.9960 7 1 v.top 74 0.9723 7 1 v.top 75.5 0.8975 7 1 1.5'top 76 2.4 6.5 28.3 0.8513 7 1 mid 77 3.0 6.4 29.7 42.6 18.3 0.8320 7 1 btm 77.5 2.5 6.3 28.5 42.7 20.1 0.9103 7 2 top 78 0.8815 7 2 mid 78.5 1.6 4.6 14.6 0.9620 7 2 1.5'btm Unit 6 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 92' 1.3% 5.7% 27.3% 25.1% 40.6% 0.3473 8 3 2'btm 92 0.2160 8 3 2'btm Unit Sb Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 94' 6.1% 6.8% 21.2% 36.6% 29.3% 0.4665 8 3 btm 94.5 3.2 7.2 20.6 38.6 30.5 0.6118 9 1 top 94.5 0.5511 9 1 top
102.5 0.2983 9 3 1.5'btm 102.5 0.3978 9 3 1.5'btm 103 0.5320 9 3 l'btm 103 1.0 3.3 25.4 41.8 28.5 0.7427 9 3 l'btm 104 3.5 8.0 25.3 0.2114 9 3 v.btm 104 0.3283 9 3 v.btm 115.5 5.1 12.8 36.1 0.5323 1 1 3 top 116.5 4.7 12.5 39.6 27 16.� 0.6490 1 1 3 2.5'btm 75 W-46 Textural and X-Ray Difraction Res ults (Cont.)
Unit Sa Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 96.5' 0.8220 9 1 mid 97.5 4.0% 8.3% 30.2% 31.6% 25.8% 0.7738 9 1 btm 100 3.4 9.4 25.8 37.6 23.8 0.8248 9 3 v.top 100.5 . 0.8128 9 3 top 101.5 0.6338 9 3 1.S'top 113 4.5 11.5 34.9 35.2 13.8 0.8157 11 2 2'btm 113.5 4.6 12.3 36.6 0.9835 11 2 mid
117 0.8400 11 3 mid 118 0.8245 11 3 v.btm 122 7.2 10.0 39.4 30.5 12.9 0.8160 12 2 top 123 0.7500 12 2 mid 124 6.1 13.3 37.3 30.7 12.6 0.8593 12 2 1.S'top
Unit 2 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10- A CR Bag @ 235' 0.5925 24 1 2'btm 235.5 20.8% 24.1% 9.7% 25.5% 19.9% 0.3754 24 2 top 237 21.7 27.2 8.6 26.1 16.4 0.5868 24 2 2'top 238 0.6213 24 2 l'btm
240 25.9 23.3 12.1 23.1 15.6 0.6134 25 1 top 240 0.5892 25 1 top 241 22.7 19.6 13.1 28.6 16 0.6425 25 1 2'top
Unit 1 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 238.5' 11.2% 16.6% 20.2% 28.9% 23.1% 0.7638 24 2 l'btm 239.5 9.7 14.2 17.2 29.2 29.7 0.4682 24 2 btm 241.5 0.4282 25 1 2'top 242 11.0 16.1 20.6 30.8 21.5 0.5334 25 1 2'btm 245 9.8 16.1 24.1 29.7 20.4 0.3910 25 1 btm Appendix D W-44 Textural and X-Ray Diffraction Results
76 77 W-44 Textural and X-Ray Diffraction Results
Unit 8 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 43' 3.1% 8.5% 43.7% 0.9130 4 2 l'BTM 44.5 3.7 9.2 45.5 0.9750 4 3 l'TOP MID 45 4.8 10.1 37.7 32.4% 15.0% . 1.0030 4 3 45.5 0.9035 4 3 2.5'btm 47 2.9 8.1 40.0 0.8830 4 3 V.BTM 47.5 3.9 9.2 36.0 1.1550 4 4 V.TOP 48.5 3.6 9.6 38.8 0.9950 4 4 MID 50 3.2 9.7 37.8 33.3 15.9 1.1510 4 4 V.BTM 52.5 3.0 10.7 41.6 1.1830 4 5 MID 54.5 1.1 6.3 40.1 4 5 V.BTM 55 2.4 8.2 25.0 41.2 23.3 1.3450 5 1 top 58 4.0 13.3 39.3 1.1798 5 2 v.top 59 3.5 14.3 39.8 26.5 15.8 1.4623 5 2 mid 61.5 4.1 13.4 38.4 1.4805 5 3 6"btm 63.5 3.1 13.5 39.1 1.2088 5 4 mid 65 3.3 11.6 33.5 33.4 18.1 1.3468 6 1 v.top 66 1.4690 6 1 top 69 1.4135 6 1 l'btm 70.5 4.6 12.3 32 31.6 19.6 1.6663 6 2 top 72.5 4.6 12.3 32.0 32.0 19.2 1.3843 6 2 mid 75 1.4480 6 2 v.btm
Unit 7 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 75.5' 3.3% 6.9% 24.2% 48.1% 17.4% 0.9540 7 1 top 76 4.9 7.6 25.7 42 19.8 0.8330 7 1 2'btm 76 0.8840 7 1 2'btm 77 2.3 5.5 24.0 0.8395 7 1 v.btm 77.5 1.7 5.1 21.7 53.4 18 0.9985 7 2 top 78.5 1.6 4.4 18.3 0.6778 7 2 mid 78 W-44 Textural and X-Ray Difraction Results (Cont.)
Unit 6 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 82' 1.2% 8.5% 17.3% 49.6% 23.4% 7 3 v.btm 83 1.2 8.9 17.7 51.2 21.0 7 3 v.btm 83.5 1.4 7 18.1 49 24.5 7 4 3'btm 84 1.7 12.1 28.0 7 4 l'top 84.5 1.6 13.0 26.9 38.7 19.8 7 4 6"btm 84.5 1.2 11.9 27.2 38.4 21.2 7 4 6"btm
Unit 5 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 100' 1.2% 4% 15% 53.7% 26.1% 8 5 2'btm 103 2.6 7.7 23.6 39.2 26.9 0.7450 8 6 2'btm 104.5 0.8068 8 6 btm 106 5.6 10.1 26.3 0.8868 9 1 mid 106 0.7867 9 1 mid 107.5 2.4 4.3 19.4 44.6 29.3 0.7143 9 2 6"top 109 2.9 5.9 20.1 0.8133 9 2 v.btm 109.5 0.9868 9 3 top 110.5 2.8 7.0 24.7 41 24.5 0.7478 9 3 mid 112 0.7773 9 3 v.btm 112.5 0.7805 9 4 top 113.5 2.2 4.1 16.3 0.7505 9 4 mid 115 3.8 11.4 29.9 34.8 20.2 0.9115 9 4 v.btm Unit 4
Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 116.5' 13.0% 17.4% 25.3% 1.0943 10 2 6"top 117 11.3 18.0 28.7 1.1433 10 2 v.btm 117.5 6 14.9 37 29.8% 12.3% 1.1037 10 3 6"top 119 5.8 29.4 22.5 1.0203 10 3 v.btm 120 4.9 13.2 35.6 32.9 13.4 1.1390 10 4 l'top 120.5 6.5 13.7 36.1 1.1455 10 4 v.btm 121 6.4 14.7 37.9 1.2633 10 5 mid 124 3.0 9.1 35.7 32.8 19.4 1.1918 10 6 l'btm 79 W-44 Textural and X-Ray Diffraction Results (Cont.)
Unit 4 (Cont.) Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 125.5' 2.9% 8.8% 36.4% 0.9968 11 1 top 127 1.0535 11 1 mid 127.5 3.0 7.6 35.0 1.1150 11 1 l'btm 129 2.5 7.6 35.3 38.8% 15.9% . 0.7585 11 2 top 130.5 1.0050 11 2 mid 132 2.5 7.1 36.8 1.0238 11 2 v.btm 133.5 2.5 6.7 34.8 1.0365 11 3 mid 135 2.5 8 38.9 34.0 16.6 1.2280 12 1 v.top 136.5 1.1235 12 1 v.btm 137 1.0873 12 2 top 138.5 1.0638 12 2 1.5'btm 140 1.7 5.9 34.8 29.6 27.9 0.9033 12 2 2'btm 140 1.0547 12 2 v.btm 140.5 1.0378 13 1 btm 141 2.0 7.2 32.1 0.9580 13 2 v.top 143 1.4 4.5 20.6 1.0603 13 3 top 144 0.8860 13 3 mid 144.5 2.4 8.0 27.5 37.2 24.8 0.9328 13 3 l'btm
Unit 1 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 272' 5.0% 8.1% 17.5% 36.7% 32.7% 0.3842 25 4 top 273 5.4 7.5 12.5 41.0 33.6 0.4936 25 4 l'top 273.5 0.3551 25 4 mid Appendix E W-45 Textural and X-Ray Diffraction Results
80 81 W-45 Textural and X-Ray Difraction Results
Unit 7 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 70.5' 2.2% 5.8% 26.1% 46.4% 19.5% 0.6957 5 4 top 70.5 0.6790 5 4 top#2 71 2.2 5.8 25.4 5 4 6"top 72 2.6 5.7 25.9 47.4 18.4 0.9253 5 4 mid 73.5 0.8441 5 4 3"btm 75.5 2.1 5.5 21.9 42.1 28.4 0.7863 6 1 top
Unit 5b Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 85.5' 2.7% 6.9% 23.6% 35.6% 31.1% 0.5600 7 1 top 85.5 4.1 10.3 28.1 31.5 26.0 0.6162 7 1 top #2 86.5 5.3 14.9 37.3 24.9 17.7 0.6183 7 1 1.5'bt m 86.5 0.7410 7 1 1.5'btm# 2
Unit Sa Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 110' 0.8275 8 4 top 110.5 4.9% 15.4% 33.6% 28.7% 17.4% 0.7685 8 5 top 111.5 8 5 l'top 112 0.8325 8 5 pre mid 112.5 4.9 11.8 32.8 35.2 15.4 8 5 mid 114.5 4.0 11.0 30.4 33.9 20.6 0.809 8 5 6"btm 115 5.3 12.4 35.0 0.892 8 5 v.btm 82
W-45 Textural and X-Ray Diffraction Results (Cont.)
Unit 4 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10- A CR Bag @ 115.5' 4.9% 12.2% 46.3% 25.7% 11.0% 9 1 top 117.5 4.2 13.3 46.0 · 0.9611 9 1 2'btm 118.5 3.4 11.5 45.6 27.2 12.3 1.0832 9 1 btm 119.5 2.8 10.4 40.5 1.0937 9 2 top 119.5 1.0005 9 2 top#2 120.5 2.3 7 42.6 31.1 17.1 9 2 mid
Unit 2b Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 207.5' 16.0% 26.3% 19.3% 25.6% 12.7% 1.2433 18 2 mid 208 14.5 24 18.3 27.8 15.5 1.5218 18 2 l.5'bt m 209 12.5 22.6 18.5 28.5 17.9 1.3558 18 2 btm 209 1.4335 18 2 btm 209.5 14.4 16.7 18.1 37.5 13.3 1.3860 18 3 top 211 10.2 11.2 25.9 33.3 19.4 1.2588 18 3 btm
Unit 1 and Unit 2a Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 233'* 2.5% 4.4% 19.7% 56.2% 17.2% 0.6364* 20 3 l'btm 235.5 6.9 13.8 21.5 33.8 21.0 0.3821 21 1 top 237* 4.5 6.5 19.7 0.7175* 21 1 mid 237.5* 3.5 6.7 19.8 54.1 15.9 0.9842* 21 1 l.25'btm 237.5* 0.8786* 21 1 l.25'btm 238.5* 3.8 6.1 10.5 59.2 20.4 0.6800* 21 1 btm 238.5 0.4155 21 1 btm 239* 0.6734* 21 2 top 241* .. 21 2 3'btm 243.5 6.7 11.6 16.2 38.1 27.4 0.4944 21 3 btm NOTE: * Indicates Where Unit 2a is lnterbedded Within Unit 1 Appendix F W-43 Textural and X-Ray Diffraction Results
83 84 W- 43 Textural and X-Ray Difraction Results
Unit 8 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10- A CR Bag @ 65' 1.1375 14 1 top 66 3.9% 18.2% 37.7% 14 1 l'top 66.75 2.9 13 40.1 26.9% 17.1% 1.0748 14 1 btm 67 0.1 0.643 1.1563 14 1 v.btm 67.25 3.1 12.8 39.6 27.5 17 1.1545 15 1 top 68 0.09 0.643 1.1843 15 1 l'top 68.5 2.6 11.9 35.5 25.2 24.9 1.0747 15 1 mid 70 3 11.6 39.8 24.9 20.6 1.0590 15 1 btm
Unit 7 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10-A CR Bag @ 71.5' 2.4% 6.9% 27.5% 42.3% 20.9% 0.7120 16 2 top 73 0.9093 16 2 l.5'top 73.5 3.5 6.8 26.4 46.4 16.8 0.8258 16 2 l.5'btm 75 4.5 9.0 32.4 0.8698 16 2 v.btm 75.5 4 8.6 31.9 40.7 14.8 0.9537 16 3 top 75.5 0.9770 16 3 top 78.5 4.1 9.3 37.9 37.7 10.9 0.8610 16 3 v.btm
Unit 2 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10- A CR Bag @ 214' 4.0% 5.6% 6.7% 59.9% 23.7% 0.8200 24 3 v.top 215.5 4.9 6.4 7.2 58.2 23.3 0.6865 24 3 mid
Unit 1 Coarse Med. Fine Depth Sand Sand Sand SILT CLAY 7-A/10- A CR Bag @ 217' 9.4% 11.1% 9.7% 34.2% 35.7% 0.3564 24 3 btm 217.5 10.7 17.3 16.1 31.5 24.4 0.5424 24 4 top 219 7.2 16.8 27.7 26.3 22.0 .05342 24 4 v.btm Appendix G
Student-t Test Explanation
85 86 Student-t Test Explanation
In order to perform this test the following data must be calculated for both groups A and B (Taylor, 1990):
xm : mean of group
s : standard deviation of the group
n : number of samples in group
= 2 = 1.) Calculate variances: VA s A / nA Va s\ / na
2.) Calcualte the degrees of freedom (f):
= 2 f (VA + Va )
2 2 (VA /nA -1) + (Va /na -1)
3.) Calculate the uncertainty:
t* is found in the Student-t table coresponding to the two tailed confidence interval. The degrees of freedom and the chosen confidence interval are used to locate t*. The 95% confidence interval is used as the default in this study unless otherwise noted.
° U, = t* (VA + Va) -s 87 4.) The null hypothesis is tested. The null hypothesis assumes there is no difference between two popualtions. If UA > A the null hypothesis is accepted, the means of the group are similar, the groups are not different at the chosen confidence interval.
If UA < A the null hypothesis is rejected and the means of the two groups are significantly different at the chosen· confidence interval. Appendix H Student-t Test Results Comparing 7-A/10-A Ratios Within Each Boring
88 89 Student-t Test Results Comparing 7-A/10-A Ratios Within Each Boring
Boring and Unit t-value UA A W-46 Unit 8b 2.1689 0.1103 0.4583 W-46 Unit 8 2.0833 0.0887 0.2934 W-46 Unit 7
W-46 Unit 4b 2.1406 0.1153 0.3294 W-46 Unit 4
W-46 Unit 2 2.4207 0.0656 0.1231 W-46 Unit 1
W-44 Unit 8 2.1002 0.1449 0.3639 W-44 Unit 7
W-44 Unit 5 2.0382 0.0561 0.2604 W-44 Unit 4
W-45 Unit Sb 2.6511 0.1143 0.1921 W-45 Unit Sa 2.5428 0.0955 0.2079 W-45 Unit 4
W-45 Unit 2b 2.2338 0.1812 0.6547 W-45 Unit 2a 2.6620 0.2360 0.2811 W-45 Unit 1 Notes: All Calculations Made at the 95% Confidence Interval Unless Noted 90 Student-t Test Results Comparing 7-A/10-A Ratios Within Each Boring
Boring and Unit t-value ULi W-43 Unit8 2.2474 0.0862 0.2475 W-43 Unit 7
W-43 Unit 2 12.4429 0.8406 0.2763 2.6552" 0.2395" 0.2763 W-43 Unit 1
Notes: All Calculations Made at the 95% Confidence Interval Unless Noted " - Calculation Made at the 90% Confidence Interval Appendix I
Student-t Test Results Comparing 7-A/10-A Ratios Between Units and Landforms
91 92
Student-t Test Results Comparing 7-A/10-A Ratios Between Units and Landforms
Unit or Feature t-value UA A Tekonsha Moraine*+ 2.2559 0.3220 0.0746 Unit 8 2.763 0.8684 0.0854 Leonidas Drumlin Field*+
Unit 8 2.0703 0.1670 0.0646 Fulton Unit*+
Kalamazoo Moraine*/\ 2.1564 0.1448 0.030 Sturgis Moraine(!) **A
Bedfor Till*+ 2.2036 0.1854 0.01 Sturgis Moraine(u)**A 2.1107 0.1649 0.02 Kalamazoo Moraine*+
Sturgis Moraine(u)**A 11.0835 0.2459 0.15 Sturgis Moraine(l)**A
Notes: All Calcualtions Made at the 95% Confidence Interval * Data aquired by Monahan and Larson (1986) ,.,. Data aquired by Kindzerski (1997), from the lower unit. + Saginaw Lobe Landform or Diamict A Lake Michigan Lobe Landform or Diamict (1- Lower Unit, u - Upper Unit) Appendix J Hydrometer Result Analysis
93 94 Hydrometer Result Analysis During the hydrometer test the hydrometer bulb reading is taken (Ro), the time in minutes (t) of the reading, and the temperature of the control cylinder (°C), and the hydrometer bulb reading of the control cylinder (Zc). The oven dried sample weight, (Ws), is also used in the calculation. The following explanation demonstrates how to obtain the mass percent finer of each particle size. An Excel spreadsheet was created to perform this task. The tables referred to can be found in Wray (1986). 1) The temperature correction factor, Ct, is found in a table based on the temperature of the control cylinder. 2) The hydrometer correction reading (Re) is calculated; Re = Ro - Zc + Ct. 3) The hydrometer correction for meniscus (R) is calculated; R=Ro+l. 4) The effective depth (L) is calculated; L = 16.3 - (0.1641 , R). 5) A table is used to find K based on the unit weight of solids (clay is assumed to be 2.65 g/ cm3) and temperature.
, ° 5 6) Particle diameter (D) is then calculated; D = K ( L / t ) " • 7) The correction factor a for the unit weight of solids is found in a table. An a value of 1 is used if the assumed unit weight of solids is 2.65
3 g/cm • 8) Percent finer (%f) is calculated; %f = 100 , Re , ( a / Ws). 9) Percent finer is plotted against particle diameter and incorporated into the sieve analysis results and the percent coarse sand, medium sand, fine sand, silt, and clay can then be extapolated. Appendix K
Centrifuge Extraction of Particles Greater Than Clay-Size From Solution
95 96 Centrifuge Extraction of Particles Greater than Clay-Size from Solution There are four considerations when determining centrifuge spin duration to extract the silt and fine sand particles from solution to obtain an exclusively clay-size particle solution. (1) The temperature of the solution. (2) The distance of the top and bottom of the solution from the center of rotation while rotating in the centrifuge cup. (3) Maximun revolutions per minute. (4) The time it takes to acellerate to maximun RPM and decelerate to zero RPM. Considerations 2, 3, and 4 must be evaluated for the centrifuge in use. The spin duration time then only depents on the temperature of solution. The following formula is used to calculate spin duration, T, in seconds (Starkey, 1984):
Where: h is the viscosity of solution based on temperature ( determined from a table).
R1 and � are the distance, in cm, of top and bottom of the solution from the center of rotation respectively. r is the largest diameter, in cm, of particle to remain in solution, <2um = 10-4cm. N is the maximun RPM/60. Dr is the change in specific gravity of the particles in water, l.65g/ cm3 obtained by (2.65 -1).
ta and td are the centrifuge acceleration and deceleration time in seconds. 97 For the Cetifuge in the Western Michigan Soil Lb used in this study the above formula equates to:
h log (9.8/3.8) T = +40 = h {10,471.77) + 40 3.81 (10-) (252) {l.65)
This fourmula was used to create the following table which was consuled for this study: Table 14
Centrifuge Spin Times at 1500 RM
Temperature h Time Spin Time Deceleration Time 20 °C 0.01005 145.2 sec. 1 min. 55 sec. 30 sec. 21 0.00981 142.7 1 min. 53 sec. 30 sec. 22 0.00958 140.3 lmin. 50 sec. 30 sec. 23 0.00936 138.0 1 min. 48 sec. 30 sec. 24 0.00914 135.7 1 min. 46 sec. 30 sec. 25 0.00894 133.6 1 min. 43.5 sec. 30 sec. 26 0.00874 131.5 1 min. 41.5 sec. 30 sec. 27 0.00855 129.5 1 min. 39.5 sec. 30 sec. 28 0.00836 126.3 1 min. 36 sec. 30 sec. BIBLIOGRAPHY
Bhattacharya, N., 1962, Weathering of Glacial Tills in Indiana, Part I. Clay Minerals, Geological Society of America Bulletin, v.73, p. 1007-1020. Brady, N.C., 1990, The Nature and Properties of Soil, 10th. Edition, Macmillan Publishing Co., Inc., 323 p. Carrol, D., 1970, Clay Minerals, A guide to their identification: Geological Society of America Special Paper 126, 88p. Curry, B., Kathy, KG., Berg,R.C., 1994, Quaternary Geology of the Martinsville Alternative Site, Clark County, Illinois, A proposed low level radiaoactive waste diaposal site, Circular 556, Illinois State Geological Survey, Champaingn, IL. Dodson,Russell L., 1993,Reinterpretation of the Northwest Portion of the Tekonsha Moraine, South-Central Michigan, Physical Geography, Vol. 14, No. 2, pp. 139-153. Dorr, John A., 1970, Geology of Michigan, University of Michigan Press, Ann Arbor. Dreimanis, A., 1977, Late Wisconsinan glacial retreat in the Great Lakes region, North America, New York Academy of Science Annals, 288: 70-89. Farrand, W.R., and Eschman, H. B., 1970, Geology of Michigan, University of Michigan Press, Ann Arbor, 476 p. Farrand, W.R., and Eschman, H. B., 1974, Glaciation of the southern penninsula of Michigan, a revew, Michigan Academian, Vol. 7, No. 1, pp. 31-56. Finkbeiner, 1994, Subsurface Glacial Geology of the Area Between the Tekonsha and Kalamazoo Moraines, Kalamazoo County, Michigan, M.S. Thesis, Department of Geology, Western Michigan University, Kalamazoo, Mi., 220 p. Flemming, T., 1997, communication
98 99 Frye, J. C., 1973, Wisconsinan climate history interpreted from Lake Michigan Lobe Deposits and soils, in Black, R. F., Goldthwait, R.R., and Willman, H. B., eds., The Wisconsinan Stage: Geologic Society of America Memoir 136, p. 135-152. Johnson, W. H., 1986, Stratigraphy and correlationof the glacial deposits of the Lake Michigan Lobe prior to 14 ka BP, Quaternary Sciences Reviews, 5:17-22 Johnson, W.H., Hansel, A.K., Karrow, P.F., Larson, G.L., Lowell, T.V., Schneider, A.F., 1997, Late Quarternary Temporal and Event Classification, Great Lakesw Region, North America, Quaternary Research, Vol. 47, No. 1, pp. 1-12 Kehew, A.E., 1997, communication.
Kehew, A.E., Straw, W.T., Steinmann, W.K., Barrese, P.G., Passarella, G., Peng, Wei-Shyuan, 1996, Ground-water Quality and Flow in a Shallow Glaciofluvial Aquifer Impacted by Agricultural Contamination, Ground Water, Vol. 34, No. 3, pp. 491-500
Kneller, G. R., 1964, A Geological and economic study of gravel deposits of Washtenaw County and vicinity, Michigan [Ph.D. dissert.]: Ann Arbor, University of Michigan, 247 p.
Laurin, R., 1976, Tonguing, interfingering and agrillans in the Marlette and Miami soils, Their geography, distribution, genesis, morphology, and implied practical differences, Ph.D. dissertation, East Lansing, Michigan State University, 152 p.
Leverett, F., and Taylor, F. B., 1915, The Pleistocene of the Indiana and Michigan and the History of the Great Lakes, U.S. Geol. Surv., Mon Lill. Lineback, J.A., 1979, The status of the Illinois glacial stage, In: Wisconsinan, Sangamonian, and Illinoian Stratigraphy in Central Illinois, Illinois Geological Survey Guildbook 13, pp. 69-78. Lovan, A. L., 1977, Analysis of an lnterlobate Boundary in the Wisconsinan Drift of Southwestern Michigan, Focusing in Kalamazoo County, M.S. Thesis, Department of Geol., Western Michigan University, Kalamazoo, Mi., 111 p. 100 Mahjoory, R, 1971, Clay minerology of some litho- and toposequences of soils in Michigan [Ph.D dissert.]: East Lansing, Michigan State University, 138 p. Martin, H.M. 1957, Ouline of the GeologicalHistory of Kalamazoo County, Geological Survey Division, Micigan Department of Natural Resources, Lansing.
Monaghan,G. W., 1990, Systematic variation in the clay-mineral composition of till sheets: Evidence for the Erie lnterstade in the Lake Michigan Basin, Geological Society of America, Special Paper 251:43- 49. Monaghan, G. W., 1994, Origin of clay-mineral variation in Wisconsinan age sediments from the Lake Michigan Basin, Geological Society of America North Central Section 27th Annual Meeting: Programs and Abstracts, v.26, no.5, p.A55
Monaghan, G. W., Larson, 1986, G. J., Late Wisconsinan drift stratigraphy of the Lake Michigan lobe in southwestwen Michigan: Geological Society of America Bulletin, 97: 324-328. Monaghan, G. W., and Larson, G. J., and Gephart, 1986, Late Wisconsinan drift stratigraphy of the Saginaw lobe in south-central Michigan: Geological Society of America Bulletin, 97: 324-328. Morner, N. A., Dreimanis, A., 1973, The Erie Interstade, in Black, RF., Goldthwait, RP., and Willman, H.B., eds., The Wisconsinan Stage: Geological Society of America Memior 136, p. 107-134. Nicks L., 1997, communication
Nicks L. P., Kehew, A. E., Straw, W. T., Gardner, C., Smous, A. J. Kindzierski, S. K., Fleming, A.H., Brown, S. E., 1997, Enigmatic Surface Diamicton in South Western Michigan and Adjacent Northern Indiana, Geological Society America, 1997 Abstracts with Programs North-Central Section, Vol. 29, No. 4, p. 63 Reick, Richard L., Winters, Harold A., Mokma, Delbert L., Mortland, Max M., 1979, Differentiation of Surficial Glacial Drift in Southeastern Michigan from 7-A/10-A X-ray Diffraction Ratio of Clays, Geological Society of America, Part I, Vol. 90, pp. 216-220. 101 Ritter, Dale F., Kochel, Craig R., Miller, Jerry R., 1995, Process Geomorphology third edition, Wm. C. Brown Publishers, Dubuque, 546 p. Shah, B. P., 1971, Evaluation of Natural Aggregates in Kalamazoo County and Vicinity, Michigan, Unpubl. Ph.D. Dissertaion, Department of Geol., Michigan State University, East Lansing, Mi., 193 p.
Starkey, Harry C., Blackmon, Paul D., Hauff, Phoebe L., 1984, The Routine Mineralogical Analysis of Clay Bearing Samples, U.S. Geological Survey Bulletin 32, U.S. Geological Survey, Reston. Taylor, John K., 1990, Statistical Techniques for Data Analysis, Lewis Publishers, Chelsea, 200 p. Wayne, W. J., and Zumberge, J. H., 1965, Pleistocene Geology of Indiana and Michigan, in Wright, H. E., and Frey, D. G., (Ed.), Quaternary of the United States, Princeton University Press, Princeton, N. J., p.63-84. Western Michigan University, Department of Geology, College of Arts and Science, 1981, Hydrogologic Atlas of Michigan, Kalamazoo, Plate 13 Willman, H.B., Glass, H.D., Frye, John C., 1966, Mineralogy of Glacial Tills and their Weathering Profiles in Illinois, Part II Weathering Profiles, Illinois Geological Survey, Urbana, 76 p. Wray, Warren K., 1986, Measuring Engineering Properties of Soil, Prentice-Hall, Inc, Englewood Cliffs, 276 p. Zumberge, J. H., 1960, Correlation of Wisconsinan drifts in Illinois, Indiana, Michigan, and Ohio: Geological Society American Bulletin, 71: 1177-1188. N 4 4 w-46 w-43 w-45 ,__w�--, � :::::::::----1 so o, PLATE 1. Surface Diamicton O' 200'.
LEGEND 25'
Diamiclon Unit Unit 8 D 50' Fulton Till □ Sand and Gravel . . . . .· ... "Unit 6 Unit Sb- I - I Lacustrine Deposit 100'
Unit 4
Unit 3
Unit 3
Unit 2
Unit 1
Lacustrine and Shale
Lacustrine and Shale