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Journal of Taphonomy

2011

Available online at www.journaltaphonomy.com

Eren et al.

VOLUME 9 (ISSUE 3)

Flaked Stone Taphonomy: a Controlled Experimental Study of the Effects of Sediment Consolidation on Flake Edge Morphology Metin I. Eren* Department of Anthropology, University of Kent, UK

Andrew R. Boehm, Brooke M. Morgan, Rick Anderson Department of Anthropology, Southern Methodist University, USA

Brian Andrews Department of History and Political Science, Rogers State University, USA

Journal of Taphonomy 9 (3) (2011), 201-217. Manuscript received 21 October 2011, revised manuscript accepted 22 January 2012. Sediment consolidation can influence both stone flake artifact inclination and vertical displacement. In this paper we present a novel experiment for investigating the effect of sediment consolidation on the morphology of stone flakes. Focusing specifically on the variables of gravel size and pressure, we show that sediment consolidation does not appear to result in the creation of retouched assemblages from nonretouched ones. Bend-break fractures via sediment consolidation did occur at higher frequencies, and as such the occurrence of bend-breaks needs further experimentation to tease out other specific contexts in which they occur. Overall, however, our experimental results suggest that in most cases archaeologists should not be concerned with sediment consolidation altering the appearance of flaked stone assemblages. Keywords: TAPHONOMY, FLAKED STONE TOOLS, EXPERIMENTAL ARCHAEOLOGY, SEDIMENT CONSOLIDATION, GRAVEL, PRESSURE

Introduction: the death of flaked stone? As any reader of the Journal of Taphonomy well knows, ““taphonomy”” was originally defined as

““the study of geological processes of the transition of animal remains from the biosphere into the lithosphere”” (Efremov 1940:88). Stemming from the greek word ““taphos,””

Article JTa119. All rights reserved.

*E-mail: [email protected]

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meaning ““tomb,”” faunal taphonomy now encompasses processes that deal not only with burial, but also processes of death (e.g. hunting), occurrences between death and burial (e.g. fungal markings; butchery), and even instances of exposure and re-burial. Essentially, the taphonomic study of archaeological faunal remains aims to understand any and every circumstance that may have affected the context and appearance of those remains between the animal’’s death and modern discovery (Dominguez-Rodrigo et al., 2011; Lyman, 2010). The notion that a flaked stone artifact interacts with the natural environment after hominin discard, and that the natural environment may play a significant role in altering that artifact’’s final cultural context and appearance, has been long acknowledged if not always correctly identified (e.g. Evans, 1862). It is now generally accepted that flaked stone taphonomy should be understood before any behavioral interpretation is made from a lithic assemblage (Eren et al., 2010:3010; Hiscock, 1985). The question that remains: what are the boundaries of a flaked stone taphonomy sub-discipline? There is a natural epistemological boundary in faunal taphonomy, i.e., the death of an animal (Lyman, 2010:3). Clearly no such divide exists for lithic artifacts, and therefore we must explicitly, if arbitrarily, demarcate one. Following numerous researchers (e.g. Dibble et al., 1997; Hiscock, 1985; White, 1979), we define flaked stone taphonomy as the subfield identifying and analyzing the processes affecting the appearance and context of lithic artifacts subsequent to their cultural use lives1. Thus, a flaked stone taphonomic process is not intentionally cultural, social, or behavioral (e.g. heat treatment, butchery), only geological or natural (e.g. erosion, sediment consolidation, trampling - see Appendix 1).

In some cases the line between flaked stone taphonomic and cultural processes may appear fuzzy. Based on our definitions above for ““flaked stone taphonomy”” and ““flaked stone taphonomic processes””, we suggest it is helpful to consider hominin intention. For example, a buried Aurignacian carinated scraper may have been dislodged from its original cultural context by later Gravettian foragers digging a grave. In this instance, though humans are responsible for the displacement of the scraper, and digging a grave is a cultural behavior, that behavior was not purposefully applied to the scraper. As such, the process affecting the context of the scraper is a taphonomic one. But if that scraper was then picked up by a Gravettian forager and used, the resulting polish would stem from a cultural process because it was intentionally applied by a hominin, and thus not taphonomic. None of this is to say that distinguishing between taphonomic and cultural processes is not challenging, and occasionally impossible, given that (1) analytical or inferential equifinality may exist and (2) hominin intention is an inference, not a certainty. Indeed, it is important to understand and document where equifinality may exist so that archaeologists do not make unwarranted assumptions or conclusions. And that is our principle goal here - to attempt to understand whether a specific flaked stone taphonomic process modifies stone tools in a fashion that might be mistaken as cultural. Specifically, this particular experiment’’s motivation stemmed from our curiosity as to whether a flaked stone artifact’’s edges might be modified via sediment consolidation (Andrews, 2006) in such a way that it could be mistaken as hominin modification (e.g. retouch or bend-breaks). Indeed, we had a precedent to our inquiry: other taphonomic

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processes effecting flaked stone, like trampling, have already been shown to result in ““retouched”” tools (e.g. McBrearty et al., 1998). In order to start examining sediment consolidation and its influence on the morphology of stone flakes, we decided to pursue an approach that was highly-controlled, as opposed to one more actualistic2, by honing in on two variables: pressure and gravel size. Looking at only these two variables in isolation provides two immediate benefits. First, the focused examination of individual variables makes the results here potentially (if only partially) applicable to numerous other contexts beyond sediment consolidation. Second, the controlled examination of specific variables will facilitate a clearer understanding of their role in more actualistic sediment consolidation experiments pursued in the future.

(1) a significant percentage of artifacts deposited at an original inclination angle between 3-89 degrees will undergo a reduction in inclination angle of 3 or more degrees as a result of consolidation (ibid. 468). (2) the degree to which artifact inclination angles flatten increases as the amount of compressive stress increases (ibid. 469). (3) artifacts undergo similar amounts of downward vertical displacement regardless of original inclination angle and regardless of edge orientation (ibid. 471). (4) the amount of downward vertical displacement increases as the amount of consolidation increases (ibid. 471). (5) artifact attributes (size class, length, width, thickness, weight, area, volume) are not significantly related to the amount of inclination change or vertical displacement (ibid. 469, 471).

Sediment consolidation ““Consolidation”” refers to change in sediment volume in response to normal overburden loading (Andrews, 2006:462; Taylor, 1948). When sediments undergo consolidation, complex changes in the distribution of solid matter, water, and air within the sediment take place. The net result of these changes is rearrangement of the solid particles within the sediment as the void space is reduced (Andrews, 2006:462). Theoretically, as the weight of overburden is increased, sediment will undergo a reduction in void space, effectively forcing solid particles into closer association (Figure 1). Andrews (2006) recently examined the effects of sediment consolidation on artifact inclination and vertical displacement, using an air-bladder pressure-system (see ibid. 464-465). Among other results, he found that:

These results suggest that sedimentartifact interactions via consolidation are dynamic and significant, leading to our principle hypothesis. If archaeological deposits contain gravels, it seems reasonable to hypothesize that as sediment consolidation proceeds those gravels could modify flaked stone edges in a way that might subsequently be interpreted by lithic analysts as cultural (i.e. retouch or bend-breaks). Experimental protocols Materials In order to examine the combined effect of pressure and gravel size on the morphology of flaked stone edges, it was necessary to construct an apparatus that could contain both gravel and stone flakes, while at the

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Figure 1. Idealized model of sediment consolidation (a). As overburden weight increases, a reduction in void space occurs (b), resulting in a closer association of solid particles and objects within the sediment. Adopted after Andrews (2006).

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same time bear varying amounts of force without collapsing, or its sides bursting outward. To serve this purpose, one of us (A.R.B.) designed and constructed the device depicted in Figure 2. The specifications of this device are available in the Figure 2 caption. In order to exert downward force (pound-force, lbF) on the device’’s top lid, and hence to the gravel and ““buried”” stone flakes within, we employed a K.R. Wilson 37FX 75 ton capacity hydraulic press (Figure 3). The press was housed in the Department of Earth Sciences at Southern Methodist University. The force gauge on the press was a simple needle and dial, which was not conducive to accurate lbF readings. Thus, to measure the amount of downward force we used a LBM-2.5K compression load-button load-cell connected to a DPM-3 load-cell display (Figure 4). The load cell was highly accurate with a non-repeatability of 0.05%, and a nonlinearity of 0.15%, of rated output. Three gravel sizes from the Wentworth (1922) scale were used as the archaeological ““deposit”” in which the experimental stone flakes were suspended: (1) fine gravel (4-8 mm in diameter), (2) coarse gravel (16-32 mm in diameter), and (3) very coarse gravel (32-64 mm in diameter). The choice to have a matrix comprised entirely of gravel was a conscious one. If ““cultural”” modification on flaked stone artifacts is infrequent in archaeological deposits comprised entirely of hard gravels, we can safely assume deposits where gravel is only a percentage will follow suit. However, if the frequency of ““cultural”” modification is ubiquitous in a layer composed entirely of gravel, we can then systematically reduce the quantity of gravel in experimental deposits of future trials to pin point when modification begins to occur.

The experimental stone flakes were fresh bifacial thinning flakes knapped from Texas Georgetown flint by M.I.E. Methods Four pressures were applied to each of the three gravel sizes (and embedded artifacts), resulting in a total of 12 ““crushing trials”” (4*3 = 12 trials, Table 1). The four pressures were calculated from the downward lbF applied by the hydraulic press, approximately equal to 500 lbF, 1000 lbF, 1500 lbF, and 2000 lbF, respectively (Table 1, column 3). These values were converted into gram-forces (gF, 1 lbF = 453.5923 gF, Table 1, column 4), which were then divided by the square area of the box lid (441 cm2) to calculate an approximated pressure applied to the box’’s contents (Table 1, column 5). Because of the intense compression caused by the hydraulic press, effects of overlying gravels on compression were rendered insignificant and were not considered. Following Andrews (2000, 2006), it is possible to roughly estimate the depth at which these pressures can occur (assuming homogenous sediment). The pressures used here, and thus estimated depths (Table 1, column 6), are on average much greater than those examined by Andrews3 (ibid.). Similarly to the choice to use a sediment matrix composed entirely of gravel, the high pressures applied here were consciously chosen for this pilot. If the frequency of ““cultural”” modification on flaked stone artifacts at high pressures is little to none, we can safely assume lower pressures will probably not cause frequent, or any, damage either. But if the frequency of modification is prevalent at high pressures, we can systematically apply less and less pressure

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Figure 2. The device (dubbed ““Ironclad Alpha””) used to contain both the gravel and artifacts. A wooden base (37 cm by 37 cm) was constructed with short ““walls”” (1.5 cm thick, 4.5 cm high) attached to its sides (a). The base supported a removable enclosure with dimensions 21 cm by 21 cm by 20.5 cm and walls 1.5 cm thick (b). The enclosure was then surrounded by four metal plates, with dimensions 20 cm by 20 cm by 5 cm (c). To ensure stability, both the enclosure and metal plates were constrained by metal rods, which could be tightened or loosened as desired (d). The enclosure lid was a piece of wood (21 cm by 21 cm by 1.5 cm). It was upon this lid that the load-cell was placed and the hydraulic press exerted force (see text and figures 4 and 5).

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Gravel size

Medium

Medium

Medium

Medium

Small

Small

Small

Small

Large

Large

Large

Large

Trial

1

2

3

4

5

6

207

7

8

9

10

11

12

2093

1578

1035

533

2064

1607

1045

520

2021

1536

1004

515

Pound-force (lbF)

949368

715768

469468

241764

936214

728922

474004

235868

916710

696717

455406

233600

Gram-force (gF)

2152

1623

1064

548

2122

1652

1074

534

2078

1579

1032

529

Pressure (g/cm2)

1434

1082

709

365

1414

1101

716

356

1385

1052

688

352

Rough estimate depth (cm)

1

1

0

1

0

0

0

0

0

0

0

0

Cultural modification

3

2

0

1

0

0

0

0

5

1

3

3

Bendbreak

5

2

4

1

7

5

1

0

5

4

4

3

Chip

Table 1: Variables, data, and calculations used in the experiment. To see how the rough estimate depth (column six) was calculated, please see endnote #3. Please also see endnote #3 to compare the pressures and rough estimate depths with Andrews (2000, 2006).

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Figure 3. K.R. Wilson 37FX 75 ton capacity hydraulic press. Image acquired from: http://www.mvalues.com/ xdetails.cfm/QN/141521, accessed on 27 august 2011.

in future trials to pin point when damage begins to occur. Twelve artifacts were carefully placed in the box during each trial, four on the bottom, four in the middle, and four at the top. Each artifact ““deposit”” had gravel carefully placed below and above it. Once the box was filled with artifacts and gravel, the box lid was placed on top, and the compressionload button centered between the lid and the hydraulic press (Figure 5). The press hand crank was turned until the target lbF was achieved. To ensure a clear reading of the DPM-3 load-cell display, it was video recorded and played back in slow motion to capture the exact peak of applied lbF. Once a trial was finished, the artifacts were slowly ““excavated””

by hand, sometimes a pebble at a time, to make sure no further damage was done. Each artifact was photographed before and after its trial (with a Nikon d5000 (DSLR) with an AF-S Nikkor 18-55 mm VR lens), resulting in a total sample of 1434 stone flakes examined. Both the post-trial artifacts themselves and photographs were compared to the pre-trial photographs to determine the extent, if any, of damage. All specimens are retained by M.I.E. We categorized the resultant modification into three broad classes: (1) Cultural modification - numerous continuous small flake removals perpendicular to a flake’’s edge that could be interpreted as retouch or use-wear. (2) Bend-break - a snap across a significant section of a stone flake. Bend-breaks may be interpreted as cultural or non-cultural in nature (Jennings, 2011). (3) Chip - a single (i.e. <15 mm) flake removal perpendicular to a flake’’s edge. A chip would not normally be interpreted as culturally applied.

Figure 4. The LBM-2.5K compression load-button load-cell (a) and DPM-3 load-cell display (b).

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Figure 5. The experimental set-up. The DPM-3 load-cell display (a) was connected to the LBM-2.5 K load-cell (b), here covered in a plastic Ziplock bag to avoid getting hydraulic lubricant on it. The device used to house the gravel and artifacts (c) was centered under the press (d). The load-cell was placed in between the press and the lid of the device (e) after the latter was filled with gravel and artifacts. Downward force was controlled by the press hand-lever (f).

Results Of the 143 flaked stone artifacts, only 575 (39.8%) showed any sort of modification (Table 1, columns 7-9). To our surprise, only three (2.1%) of the 143 flaked stone artifacts exhibited anything that might be interpreted as cultural modification (Figure 6). All three examples occurred in the large gravel, in the 500, 1500, and 2000 lbF trials, respectively. Recall that even the 500 lbF trial represents an extremely high pressure, in a ““deposit””

comprised entirely of gravel. Given these extreme circumstances, any concern regarding sediment consolidation creating ““retouched”” assemblages from non-retouched ones should be assuaged. Eighteen of the 57 specimens showing modification were bend-breaks (Figure 7). Eighteen is 12.5% of the 143-specimen sample. None of the bend-breaks occurred in the small gravel, clearly a significant non-association. As such, if we ignore all specimens from the small gravel trials (n=48),

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Figure 6. An example of one of the three ““retouched”” specimens. Top: the stone flake after its trial but before its removal from the device. Bottom: the stone flake, debtiage, and close-up of the ““retouched”” edge.

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Figure 7. An example of one of the 18 bend-break specimens. Top: the broken stone flake after its trial but before its removal from the device. Bottom: the stone flake, and a close-up from the fracture.

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bend-break frequency increases to 18.9% (18 of 95 specimens), suggesting that flakes suspended in medium to large size gravels under high pressures will result in numerous bend-break occurrences. Though non-cultural, we note in passing that chips (Figure 8) comprised the largest class of modification, occurring on 41 of the 57 modified specimens (28.6% of the 143-specimen sample). Summary and discussion Our pilot experiment examining the possible effect of sediment consolidation in the creation of flaked stone specimens that appear to be culturally modified yielded a negative result. Despite the extreme circumstances in which our experimental flakes were placed (high pressures, deposits comprised entirely of gravel), the results indicate that sediment consolidation will not result in the creation of retouched assemblages from non-retouched ones. Indeed, even the creation of individual ““retouched”” tools via sediment consolidation seems to be an isolated occurrence. The creation of bend-breaks did occur with some regularity in medium to large-size gravels (but not at all in small gravels). As such, in terms of bend-breaks, future experimental trials should examine lesser pressures and sediments with smaller percentages of gravel to target when high bend-break frequencies commence. Numerous Paleolithic and Paleoindian assemblages have been interpreted as possessing hominin-caused bend-breaks and snaps (see references in Jennings, 2011). As such, our results do speak to two prominent proposed Pre-Clovis sites, the Topper site in South Carolina (Goodyear, 2005), and the Debra L. Friedkin site in Texas (Waters et al., 2011).

The deposit 2d at Topper in which bendbreak ““tools”” occur is comprised of alluvial sand and occurs approximately 2 meters below the modern-day ground surface (see Figure 7 in Goodyear, 2005: 109) - a much less stressful context than examined experimentally here. Likewise, the bend-break tools of the ““Buttermilk Creek Complex”” at the Debra L. Friedkin site are contained within a colluvial clay with little to no gravel, only 1.25 meters below the surface (Waters et al., 2011). Until identification analyses like those proposed in Jennings (2011) are conducted on both assemblages, the jury is still out whether these tools were culturally or taphonomically created. However, based on our experimental results it seems reasonable to suggest that the bend-breaks at both sites were not created via sediment consolidation. Future experimental trials examining sediment consolidation and edge modification should focus on more brittle toolstones, like obsidian. Additionally, following Andrews (2006), sediment deposits that are left to ““settle”” for a number of days should eventually be examined and compared to the pilot results here. More broadly, we feel our methodology, or one similar to it (e.g. Andrews, 2006), may have potential for examining modification via sediment consolidation of non-lithic artifacts, especially bone. Speculatively, we also wonder whether sediment consolidation processes might, in some buried contexts, produce marks similar to cut-marks or other bone modification. Acknowledgements M.I.E. is financially supported by a Leverhulme Early Career Fellowship. During the experimental phase of this research M.I.E. was financially supported by a National Science Foundation

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Figure 8. An example of one of the 41 chips removed from a stone flake’’s edge.

Graduate Research Fellowship, the Southern Methodist University Anthropology Department, and by Mustafa, Kathleen, and Nimet Eren. B.M.M., A.R.B., and R.A. are financially supported by the Southern Methodist University Anthropology Department and the QUEST Archaeological Research Program. We would like to thank David Meltzer and the QUEST Archaeological Research Program for funding the purchase of the Georgetown flint from the Neolithics Flintknapping Supply House (www.neolithics.com). Thanks to Carl Mulcahy for access and use of the equipment in the Roy M. Huffington Department of Earth Sciences Industrial Lab. We are appreciative to Dave Kelly of Transducer Techniques, Inc.

(http://www.transducertechniques.com/), who was instrumental in helping us to pick the appropriate load-cell. Thanks to Ross Crain (http://www.spec2000.net/), who was helpful in discussing depth estimation from pressure, and to Norman Heglund, who provided us with a fascinating discussion of elephant foot pressure, unfortunately an avenue we decided not to pursue in this paper. Thomas Adams and John Graf provided thoughtful and useful discussions on the variables examined and experimental methodology. We are grateful to Rebecca Catto, Manuel DominguezRodrigo, Thomas Jennings, Robert Patten, and two anonymous reviewers for reading over an earlier version of this manuscript.

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Endnotes

References

1. We encourage the reader to see Lyman’’s (2010) discussion of the definition and history of the term ““taphonomy.”” In his paper, Lyman (2010:13) asks, ““does the term (signifying a concept) help us get some analytical work done by having a particular definition?”” He answers: ““I suggest it does because it specifies a very particular field of inquiry, materials constituting that field, and attendant analytical methods.”” It is in this spirit that we define the sub-field of flaked stone taphonomy. If how we use the term ““taphonomy”” here is different from Efremov’’s (1940) original conception, so be it. It would not be the first time a scientific term has been appropriated and redefined, another notable example being ““middle range theory”” (Shott, 1998). As such, we agree with Dominguez-Rodrigo et al. (2011), who argue that taphonomy can be used to study non-organic materials.

Andrews, B. (2000). Sediment compaction and archaeological site formation. Unpublished M.A. Thesis, University of Wyoming, Laramie. Andrews, B. (2006). Sediment consolidation and archaeological site formation. Geoarchaeology, 21: 461-478. Dibble, H., Chase, P., McPherron, S. & Tuffreau, A. (1997). Testing the reality of a ““living floor”” with archaeological data. American Antiquity, 62: 629-651. Domínguez-Rodrigo, M., Fernández-López, S. & Alcalá, L. (2011). How can taphonomy be defined in the XXI Century? Journal of Taphonomy, 9: 1-13. Efremov, I. (1940). Taphonomy: new branch of paleontology. Pan-American Geologist, 74: 81-93. Eren, M.I., Durant, A., Neudorf, C., Haslam, M., Shipton, C., Bora, J., Korisettar, R. & Petraglia, M. (2010). Experimental examination of animal trampling effects on artifact movement in dry and water saturated substrates: a test case from South India. Journal of Archaeological Science, 37: 3010-3021. Evans, J. (1962). Flint implements in the drift: being an account of further discoveries on the continent and in England, communicated to the Society of Antiquaries. J.B. Nichols and Sons, London. Goodyear, A. (2005). Evidence of Pre-Clovis sites in the Eastern United States. In (Bonnichsen, R., Lepper, B., Stanford, D. & Waters, M., eds.) Paleoamerican Origins: Beyond Clovis. College Station: Texas A&M University Press, pp. 103-112. Hiscock, P. (1985). The need for a taphonomic perspective in stone artefact analysis. Queensland Archaeological Research, 2: 82-95. Jennings, T. (2011). Experimental production of bending and radial flake fractures and implications for lithic technologies. Journal of Archaeological Science, 38: 3644-3651. Lycett, S. & Chauhan, P. (2010). Analytical approaches to Palaeolithic technologies: an introduction. In (Lycett, S. & Chauhan, P., eds.) New Perspectives on Old Stones: Analytical Approaches to Palaeolithic Technologies. New York: Springer, pp. 1-22. Lyman, R. (2010). What taphonomy is, what it isn’’t, and why taphonomists should care about the difference. Journal of Taphonomy, 8: 1-16. McBrearty, S., Bishop, L., Plummer, T., Dewar, R. & Conard, N. (1998). Human trampling as an agent of lithic artifact edge modification. American Antiquity, 63: 108-129. Shott, M. (1998). Status and role of formation theory in contemporary archaeological practice. Journal of Archaeological Research, 6: 299-329.

2. We see mathematical/computer models, highly controlled experiments, and actualistic experiments as points along the same analytical spectrum, the results of one end to be tested against the other, and reconciling explanations required in the event of disparity (see also Lycett & Chauhan, 2010). The fundamental take home message here is that intuitive assumptions must be empirically tested (Surovell, 2009), ideally and eventually, by multiple means, and that analytical repetition by multiple researchers should not be eschewed. 3. Following Andrews (2000, 2006), to estimate depth from pressure: (x g/cm2) / (y g/cm3) = D where x = pressure, y = dry bulk unit weight of sediment, and D = depth. Of course in reality one may not be dealing with a dry sediment, much less one that is entirely homogenous. To make our depths comparable to those of Andrews (ibid.), we can imagine that our gravel layer was buried underneath the sediment he used in his experiment, which had a dry bulk weight of approximately 1.5 g/cm3. Andrews’’ (ibid.) pressures (and estimated depths) were as follows: 280 g/cm2 (186 cm), 420 g/cm2 (280 cm), 560 g/cm2 (373 cm), and 700 g/cm2 (466 cm). 4. There should have been 144 stone flakes in our pilot sample (12 trials * 12 flakes = 144). Unfortunately, one specimen did not have its picture taken before its trial, and thus its post-trial morphology could not be compared to its pre-trial morphology. 5. 57 specimens showed some sort of morphological change after the trials, but five specimens exhibited both a bend-break and a chip.

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Eren et al. Surovell, T. (2009). Toward a Behavioral Ecology of Lithic Technology: Cases from Paleoindian Archaeology. University of Arizona Press, Tucson. Taylor, D. (1948). Fundamentals of Soil Mechanics. Wiley, New York. Waters, M., Forman, S., Jennings, T., Nordt, L., Driese, S., Feinberg, J., Keene, J., Halligan, J., Lindquist, A., Pierson, J., Hallmark, C., Collins, M. & Wiederhold, J. (2011). The Buttermilk Creek Complex and the Origins of Clovis at the Debra L. Friedkin Site, Texas. Science, 331: 1599-1603. Wentworth, C. (1922). A scale of grade and class terms for clastic sediments. Journal of Geology, 30: 377392. White, J. (1979). Sequencing in-site taphonomic processes: the lesson of the Eaton Briquets. Midcontinental Journal of Archaeology, 4: 209-220.

Appendix 1 Below is a limited compilation of topics and references pertinent to the sub-field of flaked stone taphonomy. Some references speak to numerous topics, but to avoid duplication we placed such references in only one category. References appearing in the main text reference list are not repeated below. Heat and frost flaked stone taphonomy Bertran, P., Klaric, L., Lenoble, A., Masson, B. & Vallin, L. (2010). The impact of periglacial processes on Palaeolithic sites: The case of sorted patterned grounds. Quaternary International, 214: 17-29. Bowers, P., Bonnichsen, R. & Hoch, D. (1983). Flake dispersal experiments: noncultural transformation of the archaeological record. American Antiquity 48: 553-572. Brink, J. (1977). Frost-heaving and archaeological interpretation. Western Canadian Journal of Anthropology, 7: 61-73. Edsale, J., Le Blanc, R. & Cinq-Mars, J. (2001). Periglacial geoarchaeology at the Dog Creek Site, northern Yukon. Geoarchaeology, 16: 151-176. Hilton, M. (2003). Quantifying postdepositional redistribution of the archaeological record produced by freeze-thaw and other mechanisms: an experimental approach. Journal of Archaeological Method and Theory, 10: 165-202. Johnson, D. & Hansen, K. (1974). The effects of frostheaving on objects in soils. Plains Anthropologist, 19: 81-98.

Johnson, D., Muhs, D. & Barnhardt, M. (1977). The effects of frost-heaving on objects in soils II: laboratory experiments. Plains Anthropologist, 22: 133-147. Schweger, C. (1985). Geoarchaeology of northern regions: lessons from cryoturbation at Onion Portage, Alaska. In (Stein J. & Farrand W., eds.) Archaeological Sediments in Context. Orono: Peopling of the Americas, Center for the Study of Early Man, Institute for Quaternary Studies, University of Maine, pp. 127-141. Trembour, F. (1990). Appendix F: a hydration study of obsidian artifacts, burnt vs. unburnt by the La Mesa fire. In (Traylor, D., Hubbell, L., Wood, N. & Fiedler, B., eds.) The 1977 La Mesa fire study: an investigation of fire and fire suppression impact on cultural resources in Bandalier National Monument. Santa Fe: Southwest Cultural Resources Center Professional Paper no. 28, National Parks Service, Branch of Cultural Resources Management. Viklander, P. (1998). Laboratory study of stone heave in till exposed to freezing and thawing. Cold Regions Science and Technology, 27:141-152. Rolling and tumbling flaked stone taphonomy Chambers, J. (2003). Like a rolling stone? The identification of fluvial transport damage signatures on secondary context bifaces. Lithics, 24: 66-77. Grosman, L., Sharon, G., Goldman-Neuman, T., Smikt, O. & Smilansky, U. (2010). Studying post depositional damage on Acheulian bifaces using 3-D scanning. Journal of Human Evolution, 60: 398-406. Harding, P., Gibbard, P., Lewin, J., Macklin, M. & Moss, E. (1987). The transport and abrasion of flint handaxes in a gravel-bed river. In (Sieveking, G. & Newcomer, M., eds.) The Human Uses of Flint and Chert: Proceedings of the Fourth International Flint Symposium Held at Brighton Polytechnic. Cambridge: Cambridge University Press, pp. 115-126. Hosfield, R. (1999). The Palaeolithic of the Hampshire Basin. British Archaeological Reports British Series 286. Archaeopress, Oxford. Hosfield, R. (2011). Rolling stones: understanding riverrolled Paleolithic artifact assemblages. In (Brown, A., Basell, L. & Butzer, K., eds.) Geoarchaeology, Climate Change, and Sustainability. Geological Society of America Special Paper 476, pp. 37-52. Hosfield, R. & Chambers, J. (2004). Experimental archaeology on the Afon Ystwyth, Wales, UK. Antiquity, 78 (299): http//:antiquity.ac.uk/ProjGall/ chambers/index.html Hosfield, R. & Chambers, J. (2005). Flake modifications during fluvial transportation: three cautionary tales. Lithics, 24: 57-65.

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Sediment consolidation and lithic edge morphology Hosfield, R., Chambers, J., Macklin ,M., Brewer, P. & Sear, D. (2000). Interpreting secondary context sites: a role for experimental archaeology. Lithics 21: 29-35. Shackley, M. (1974). Stream abrasion of flint implements. Nature, 248: 501-502.

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