Determining Paleoflow of Glacial Fluvial Systems in Crawford County (2)

Determining Paleoflow of Glacial Fluvial Systems in Crawford County PA

Thomas Hunter

Professor Ron Cole

Allegheny College

9/7/15

Determining Paleoflow of Glacial Fluvial Systems in Crawford County 2015

Abstract

Constructing a map of the paleoflow of glacial fluvial systems will help in the estimation of economically beneficial resources such as sand, gravel, and potential aquifers locations. The paleoflow direction will be determined by inverting the dip direction of imbricated clasts of pebble to cobble sized gravel (as discussed in [Rust,1972a]). Crawford County Pennsylvania was chosen for local location near Allegheny College and for its rich glacial deposits.

Introduction The sediments deposited by the glaciers during the late Pleistocene shape the Crawford County landscape. Till and braided river deposits fill the majority of the landscape. Construction companies in Crawford County mine for these deposits to use the sand and gravel for infrastructure construction. These are all strip mines and are also known as gravel pits. Gravel pits provide outcrops for observing the glacial deposits.

The braided river deposits are the only type of glacial deposit that will give insight to the paleoflow. Sedimentary clasts at the bottom of a fluvial system will be moved by the flow in a way that flow restriction is minimized. This is known as clast imbrication, and clasts of paleofluvial systems orientation within the matrix can be measured to determine the paleoflow direction. (Rust,1972a)

Brief Glacial History(Summary of McQuillan,1995)

During the Pleistocene there were 3 glacial advances, the first was during the late Illinoin and early Wisconsonian. The next two glaciations followed during the Kent stage of the late Wisconsonian. The glaciers though once abundant, never advanced too far south out of Crawford County most likely because of the bedrock topography, moraine deposits from earlier glaciers, and climatic changes (McQuillan, 1995).

During the interglacial periods, only parts of Crawford County went through total glacial recession, while the glacier remained in other parts of the area. The glacier ultimately retreated to the Northwest leaving behind ice lobes that melted slower after being cut off from the main glacier (by no-through valleys) and covered with sediment from meltwater streams. These lobes went on to form kame deposits and kettle lakes that define the landscape today (McQuillan, 1995)

Methods

A Brunton Compass was used to measure the orientation of clasts within lenticular beds at gravel pit outcrops. The measurements made include strike of the clasts and dip direction/ magnitude. Clast imbrications indicate the paleoflow by the inverse of the dip direction (e.g. a dip direction of 30 degrees NW indicates a paleoflow vector of 210 degrees SW) (Rust 1972a), at each site 20 to 50 strike and dips were taken combined into an average paleoflow vector for the site.

Other observations made at an outcrop include;

outcrop dimensions - the overall size of a rock wall, may contain

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more than 1 different glacial deposit

bed shape and dimensions - lenticular bedding indicates river channels while no bedding generally indicated till

clast support vs. matrix support -both give good data (imbrications present), but clast support gives more

average clast size - boulders are too big to be oriented by fluvial flow

sorting - tells how far the clasts have been transported

roundness - clasts that are well rounded orientations cannot be measured accurately by a Brunton Compass

(Field Observations can be found in Appendix 4)

Sites were found on topographic maps of Crawford County and then confirmed on Google Earth. Before entering a gravel pit (pit) a phone call or meeting with the contractor/ owner of the pit was conducted to gain permission to observe the outcrop. Pits were named after their location (road or town) and after their owners.

At many pits imbrication data could not be collected, reasons for this include;

Bed rock mine- some sites were not glacial deposits but bedrock such as shale and sandstone. Pits include; Kosurick, Donovan, Route19 farm, and Hickory Corners.

Reclamation- when a gravel pit is not being used the Environmental Protection Agency (EPA) makes contractors collapse their walls/ potential outcrops in their pits. This is because having a wall

negatively affects the turbidity of local streams. Pits include; Atlantic, Lakeland main, Lakeland ford, Lakeland honda, Hindman, Crossingville, Merrit, Maple drive, Route86, Stutsman, Gravel run, Goodwill, Quarry Rd. a, Quarry Rd. b (western).

Round clasts/ till- many glacial deposits are and therefore cannot produce good imbrication data. While other glacial deposits that have lenticular beds end up having rounded clasts that cannot be measured with a Brunton compass. Pits include; Phelps (till), Route19 field (till), Plank (till), Glover (round clasts), and Hasbrook (round clasts).

No permission- sometimes the owner of a gravel pit would be unable to give permission to enter their pits due to safety or government regulations. Pits include; Redimix main, Route322 a, Route322 b (nearer to Cochranton), Deckards, Seagertown, Mackey hill north, Mackey hill south, Hogback.

Of the 35 sites found in Crawford County only 5 were observed for successful imbrication data. These pits include; Infield, Hunter, Miller-Hunter, Miller-Centerville, and Hillside.

Paleoflow Data

Chart 1a describes the paleoflow direction at each of the sites where data could be collected.

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Pit Average Paleoflow Vector General Compass DirectionHunter 205 SWHunter-Miller 206 SWInfield 198.5 SWCenterville-Miller 152 SEHillside 198.5 SW

A rose diagram was generated for each datum of paleoflow. (Figure 1a, 1b, 1c, 1d, 1e)

Maps 1 and 2 were created using a parcel search as base map. All sites were plotted precisely using latitude and

longitude. Average paleoflow vectors are represented by arrows pointing in the direction of paleoflow, at the sites were paleoflow data was recorded. (Maps are in appendix 1)

Map 3 was created using Google Earth as base map, paleoflow sites were plotted using latitude and longitude. The sites each have a rose diagram petal pointing in the direction of paleocurrent.

Figure 1a (Centerville-Miller)

Figure 1b (Hunter-Miller)

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Figure 1c (Hunter)

Figure 1d (Infield)

Figure 1e (Hillside)

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Due to the lack of imbrication data present in Crawford County, a more accurate paleoflow map could not be constructed.

Conclusions

The meltwater streams of receding glaciers deposited sand and gravel in Crawford County. Through paleoflow data collected in the eastern half of Crawford County the glacial fluvial systems are confirmed to have a southward trend. The western

half of Crawford County did not have any available fluvial imbricated sedimentary datum, therefore the paleoflow cannot be determined.

These data reveal that present day southward drainage systems are inherited from the Pleistocene. An interesting future study of paleoflow through clast imbrications of glacial fluvial sediments would be to study other areas of the Mississippi river basin and see if the drainage patterns are inherited from the glacial systems. Another interesting future study would look at determining the protoliths of gravel clasts in glacial sediments (by its mineral content and/or sedimentary structures present).

Appendix 1: Maps

Map 1

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Map 2

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Map 3

Appendix 2: Coordinate Sheets (Northsouth is on top of Eastwest)

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Pit Degree Minute Second DecimalHillside 41 35 25.2 41.5915308

79 51 33 79.860907Infield 41 41 10.6 41.6876574

79 52 17.2 79.8731988Hunter-Miller 41 47 53.3 41.7997707

79 47 40.9 79.7963111Centerville-Miller 41 46 57 41.784103

79 49 11.2 79.8214248Hunter 41 41 4.8 41.6860392

79 57 33.4 79.9612186Hasbrook 41 38 11 41.637669

79 42 35 79.711165Glover 41 46 41.4 41.7797506

79 52 27.2 79.8759888Deckards 41 34 48.32 41.5812813

79 59 25.06 79.9922917Rt. 19 Gravel 41 41 44.46 41.6971043

80 9 22.97 80.1567086Rt. 19 BR 41 41 41.14 41.6961781

70 9 5.6 70.1518624Rt. 198 (Baseball) 41 43 44.04 41.7303872

80 9 27.49 80.1579697Maple Drive 41 45 10.39 41.7543988

80 13 31.54 80.2258997Rt. 86 Kebert 41 42 8.42 41.7037492

80 6 36.66 80.1104281Quarry Rd. South 41 41 8.18 41.6869822

79 44 8.08 79.7370543Quarry Rd. North 41 41 21.25 41.6906288

79 43 50.6 79.7322174Goodwill Rd. 41 41 13.98 41.6886004

79 42 40.93 79.7128195Donovan 41 39 12.44 41.6547708

79 43 5.88 79.7197405Stutsman 41 42 14.04 41.7053172

80 7 7.14 80.1188921Gravel Run 41 42 36.08 41.7114663

80 1 27.76 80.024445Hickory Corners 41 39 33.5 41.6606465

79 57 4.27 79.9530913Finney Rd. Small 41 48 51.41 41.8159434

79 57 18.96 79.9571898Finney Rd. North 41 48 34.32 41.8111753

79 57 36.12 79.9619775Finney Rd. South 41 48 20.2 41.8072358

79 57 38.53 79.9626499Merrit 41 47 36.44 41.7950668

80 6 13.26 80.1038995Crossingville 41 50 5.74 41.8366015

80 14 45.04 80.2463662Phelps 41 41 19.18 41.6900512

80 30 48.38 80.514498Hindman 41 40 12.45 41.6714736

80 20 16.28 80.3385421Lakeland Main 41 37 9.99 41.6206872

80 16 36.35 80.2773417Lakeland Honda 41 36 14.54 41.6052567

80 15 24.94 80.2574583Lakeland Ford 41 35 57.92 41.6006597

80 17 12.69 80.2874405Atlantic Lake Rd. 41 33 31.68 41.5599387

80 20 34.22 80.3435474Kosturik 41 30 31.24 41.509716

80 19 49.75 80.3311803Redimix 41 36 4.59 41.6024806

80 8 46.26 80.1465065Rt. 322 Kebert East 41 32 2.25 41.5350278

80 4 42.3 80.0786017Rt. 322 Kebert West 41 32 33.82 41.5438358

80 5 52.31 80.0980945

Appendix 3: paleoflow vectors9


Hunter Hunter-Miller Infield Centerville-Miller Hillside310 225 118 110 144315 302 251 142 318192 272 200 265 275125 255 137 173 231149 158 216 156 226267 265 198 56 215170 205 183 133 159107 253 187 173 158

92 201 197 124 187235 195 213 129 201256 100 74 120 209287 176 145 206 285242 164 277 160 141246 143 175 114 109220 190 216 185 271108 175 280 142 85

85 138 177 104 223253 166 215 168 155296 155 189 192 210286 185 323 186 263

72 218 175148 250 264179 200 65203 255201 155275 188202 206185 110210 189165 350245 205314 119197 239206 214266 266253 255205 348225 116212 218346 180212 161127 295126168208

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Appendix 4: Field Observation Checklists10


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Acknowledgements

Funding:

• Allegheny College • Christine Scott Nelson Faculty Support Fund

Field sites:

• R. Hunter Inc.• Glover Sand and Gravel• Hillside Stone• Centerville Sand and Gravel• Lakeland Construction • Hasbrook Sand and Gravel• Kosurick Construction

References • Dahms, D.E., 2002, Glacial stratigraphy of Stough Creek Basin, Wind River

Range, Wyoming: Geomorphology, v. 42, p. 59-83, doi: 10.1016/S0169-555X(01)00073-3.

• DeCelles, P., Langford, R., and Schwarz, R., Two New Methods of Paleocurrent Determination from Trough Cross-Stratification: , 629-643 p.

• Rust, 1972a, Pebble Orientation in Fluvial Sediments: Journal of Sedimentary Petrology, v. 42, p. 384-388.

• Rust, 1972b, Structure and Process in a Braided River: Sedimentology, v. 23, p. 213-234.

• van Rensbergen, P., de Batist, M., Beck, C., and Chapron, E., 1999, High-resolution seismic stratigraphy of glacial to interglacial fill of a deep glacigenic lake: Lake Le Bourget, Northwestern Alps, France: Sedimentary Geology, v. 128, p. 99-129, doi: 10.1016/S0037-0738(99)00064-0.

• Glacial Facies. (1984). In R. Walker (Ed.), Facies Models, Second Edition (2nd ed., Vol. 1, pp. 19-26). Hamilton, Ontario: Geological Association of Canada.

• Compton, R. (1985). Chapters 9 & 10. In Geology in the Field (1st ed., Vol. 1, pp. 169-176, 203-206). New York, New York: John Wiley & Sons.

• Schiner, G., & Gallaher, J. (1979). Groundwater. In Geology and Groundwater Resources of Western Crawford County, Pennsylvania (1st ed., Vol. 1, pp. 8-11). Harrisburg, Pennsylvania: United States Geological Survey.

• McQuillan, E., 1995, The Glacial Geology of the Townville 15 Quadrangle, Northwestern Pennsylvania [Senior thesis]: Allegheny College, .

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Determining Paleoflow of Glacial Fluvial Systems in Crawford County (2)

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