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aney Publishing A GEOARCHAEOLOGICAL FRAMEWORK FOR THE STUDY OF KARSTIC CAVE SITES IN THEEASTERN WOODLANDSAuthor(s): Sarah C. Sherwood and Paul GoldbergSource: Midcontinental Journal of Archaeology, Vol. 26, No. 2, Cave Archaeology in theEastern Woodlands (Fall, 2001), pp. 145-167Published by: Maney Publishing on behalf of the Midwest Archaeological Conference, Inc. Stable URL: http://www.jstor.org/stable/20708157 . Accessed: 10/06/2014 20:55 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp . JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new formsof scholarship. For more information about JSTOR, please contact
[email protected]. . Maney Publishing and Midwest Archaeological Conference, Inc. are collaborating with JSTOR to digitize,preserve and extend access to Midcontinental Journal of Archaeology. http://www.jstor.org This content downloaded from 128.197.26.12 on Tue, 10 Jun 2014 20:55:05 PMAll use subject to JSTOR Terms and Conditions A GEOARCHAEOLOGICAL RAMEWORK OR HE STUDY F KARSTIC AVE ITES N HE ASTERN WOODLANDS Sarah C. Sherwood nd Paul Goldberg ABSTRACT Cave deposits are complex sequences derived from multiple sources and numerous pro cesses which often operate simultaneously. These sequences are largely the result of unique microenvironments that vary between subterranean passages (beyond the reaches of natural light nd ambient onditions) nd subaerial ntrances natural ight nd ambient tempera ture and moisture conditions). In subterranean passages, where sedimentation rates are extremely low, endogenous processes are the primary sediment source, and archaeolo gists must identify artifact palimpsests on ancient surfaces. In cave entrances where sedi mentation rates are high and artifact preservation can be exceptional, both endogenous and exogenous processes must be considered. In both depositional environments human activity can generate significant amounts of sediment. With an emphasis on the karstic Eastern Woodlands, we suggest a geoarchaeological framework that focuses on the de scription and classification of the sediments. Soil and sediment micromorphology, in com bination with detailed field observation with standard descriptions nd problem-oriented ancillary techniques, rovide an effective methodological framework. he results from two profiles in 3rd Unnamed Cave, a Terminal Archaic dark zone cave site in Tennessee, illustrate he utility f this approach. Introduction Caves have been described as highly efficient sediment traps where accumula tion characteristically excels over erosion, and as sources of continuous sedi mentological records that are absent in open air sites where erosion and soil formation otherwise prevail (Collcutt 1979; Straus 1990). As such, the sediment record in cave entrances is traditionally targeted by geologists and prehistorians as an indicator of regional paleoclimate (Butzer 1981; Laville et al. 1980). The srcinal sedimentological criteria proposed for paleoenvironmental reconstruc tion in caves, although generally suitable for the periglacial environment of Pleis tocene Western Europe (e.g., Butzer 1981; Laville 1976; Laville et al. 1980), were ultimately deemed inappropriate for most environments (Goldberg 1979a; Schnurrenberger 1991). These criteria focused on clast size and morphology as a result of variation in physical weathering or changes in local chemical weather ing. Midcontinental Journal of Archaeology, Vol. 26, No. 2 ? 2001 by The University of Iowa This content downloaded from 128.197.26.12 on Tue, 10 Jun 2014 20:55:05 PMAll use subject to JSTOR Terms and Conditions 146 Sarah C. Sherwood nd Paul Goldberg It is extremely difficult to distinguish between local factors (microclimate) and broader climatic factors (macroclimate) as influences on sediment infilling (Campy and Chaline 1993; Funk 1989). For example, moisture content affecting the morphology and porosity of limestone clasts may not be the product of warm humid climates as srcinally thought, but may reflect large quantities of organic matter absorbing and retaining moisture. Sufficient C02 or acids produced from biological decay can substantially alter the post-depositional environment (B?gli 1975; Foreman and Miller 1984), a phenomenon that has also been mistaken for the basal enrichment of secondary carbonates. The same alteration can also oc cur in cold climates or anywhere calcium carbonate-enriched groundwater emerges from cave walls and ceilings (Schnurrenberger 1991). The variables of physical weathering are not well enough understood to permit regional climatic inferences (Goldberg 1979b; Straus 1990). In actuality, cave sediment sequences are strongly controlled by their microenvironment rather than regional climatic change. Microenvironmental conditions are the result of numerous factors, in cluding bedrock lithology, elevation, aspect, relation to local drainage, and hu man activity (Bonifay 1962; Campy and Chaline 1993; Farrand 1985; Goldberg 1979b; Schnurrenberger 1991). Despite the absence of an interpretive model or framework for cave sediments, there is a general geoarchaeological methodological framework that can guide our observations and the nature of the data we extract from archaeological sites in these complicated depositional environments. The goals of such a geoarchaeological framework are to render a depositional history of the cave while providing a context and chronology for the artifacts in the depositional environment, keeping in mind that sediments in archaeological sites, especially those in caves, are themselves typically artifacts of human activity. In this paper we outline a geoarchaeological perspective and methodological framework for the study of karstic deep cave sites and their subaeri al entrances. We focus geographically on Eastern Woodland cave sites, but the general frame work is applicable to most karstic sites. Much of the geoarchaeological frame work we present here srcinated in Old World archaeology and Quaternary stud ies, where there is a long tradition of geological and archaeological collabora tion. We begin with a review of the environment of deep caves and their entrances and the kinds of processes that generate and affect the sediments they contain. The techniques traditionally applied to cave sediments are briefly discussed, underscoring micromorphology as a technique to best address contextual ques tions. A brief example is provided from 3rd nnamed Cave in Tennessee, where micromorphology is enlisted to assist in the interpretation f Terminal Archaic mining activity deep within a karstic cave system. Rockshelters vs. Caves We distinguish between deep caves and cave entrances or vestibules, based on their divergent archaeological and depositional histories. Deep caves can be de This content downloaded from 128.197.26.12 on Tue, 10 Jun 2014 20:55:05 PMAll use subject to JSTOR Terms and Conditions Geoarchaeological ramework 147 fined as subterranean passages and chambers formed in bedrock that reach be yond the limits of natural light. he lithology of the bedrock can vary from basalt to sandstone and various carbonate rocks, but most caves form through the dis solution of limestone. These karst cavities form as conduits for water flow be tween input and output points (Gillieson 1996). The entrance(s) from the ground surface into a cave system can take on many different forms, including vertical shafts (Cook and Munson 1997), fissures, and lateral openings. Archaeologists exploring cave habitation sites are typically dealing with lateral openings, which provide horizontal surfaces under roofed shelters that fford stable and predict able refuge. Rockshelters, rock overhangs, and shallow rock recesses also can contain rich habitation sites. These depositional environments, unlike caves, exist completely within the reaches of natural light and ambient temperature and moisture condi tions (Collins 1990). They can be similar to cave entrances in morphology and content but lack contiguous subterranean passages and the effects of those envi ronments. The subterranean environment adds a new dimension of processes that reate and affect the archaeological site which are not typically addressed in the rocksheiter literature. Some of the processes and methods discussed in this paper are appropriate to rockshelters, but those sites are not specifically covered here. The geoarchaeology of rocksheiter sites is the focus of many previous pub lications including Farrand (1985), Collins (1990), Laville (1976), and Straus (1990). Where cave environments are discussed in geoarchaeology texts, uthors typi cally focus on rockshelters and cave entrances and regularly refer the reader to standard geologic texts for information on deep cave environments. Resources such as Ford (1976) and White (1988) are important geologic references but rarely include humans as a agents in cave sedimentation. These geoscience-ori ented sources therefore provide insufficient nformation n the face of increasing interest n cave archaeology. Cave Environments Unlike cave entrances, deep caves generally do not contain habitation debris and thick stratigraphie sequences but rather an ephemeral record of human explora tion, itual, burial, and mining (Carstens and Watson 1996; Watson 1986). While there has historically been an interest n the archaeological and paleontological deposits of cave entrances and rockshelters, deep cave sites have remained more enigmatic. This trend is changing, however, due to the archaeological research pioneered by Patty Jo Watson in the Salts and Mammoth Cave systems (Watson 1969,1974,1996; Watson and Yarnell 1966) and to cognizance of the increasing threat to these subterranean cultural and natural resources by ever-increasing recreational traffic nd urban expansion. Deep cave sites fall into two categories at the ends of the hydrological energy spectrum, the active or dynamic cave passage, and abandoned or arrested cave passage (Crothers and Watson 1993:53). These wet vs. dry environments greatly This content downloaded from 128.197.26.12 on Tue, 10 Jun 2014 20:55:05 PMAll use subject to JSTOR Terms and Conditions 148 Sarah C. Sherwood nd Paul Goldberg affect srcinal human use, preservation of the material record, and ultimately, how the caves will be investigated by archaeologists. Hydrologically abandoned cave passages are the target f most underground archaeological research in the Eastern Woodlands (e.g., Simek et al. 1998; Watson 1969, 1974, 1996). Typi cally these passages are relatively dry, with only localized drip water, and main tain a near constant temperature and humidity. Archaeological studies in active or wet cave passages are far less common. Usually the deposits in hydrologically active passages are generated by geo logic processes, typically fluvial in nature, and remain both wet and active. As a result, archaeological deposits in these active environments are difficult to re cover, and materials are rarely found in their behavioral context. However, this condition has not diminished their archaeological significance, as the simple pres ence of artifacts and human remains in these environments can be informative. For example, one of the most extensive cave archaeology projects conducted in an active cave system is the Petexbatun Regional Cave Survey in the Mayan area of Guatemala. There researchers have grappled with the methodological issues of recovering artifacts from buried, saturated clay deposits. The laborious extri cation of these finds has been worthwhile, indicating ritual activities in the caves that were previously underrepresented in open-air Mayan assemblages (Brady and Scott 1997). Wet environments are often the norm for pit caves used for prehistoric human burial in the Eastern Woodlands. Here, too, the dynamic nature of this context does not diminish the sites' significance. However, the implementation of cus tomized methods to account for taphonomic considerations (as in the Petexbatun caves) is required when interpreting hese deposits (e.g., Cook and Munson 1997; Crothers and Watson 1993; Crothers and Willey 1988). In dry or arrested cave passages, the groundwater that nce shaped the system has long since abandoned that levation and has left behind a sediment or break down surface that typically far predates human occupation in the Americas. Pa leomagnetic dating of clastic sedimentary deposits has been used successfully to establish minimum ages of regional karstic systems (e.g., Noel and Thistlewood 1989). Sediments from several inactive archaeological deep caves in the astern Woodlands indicate a minimum age at the Pliocene/Pleistocene boundary (Sasowsky et al. 1995). The paleosurface, therefore, is usually the same as the modern surface, posing contextual problems in the identification of temporal variability among artifacts lying on the same surface (Crothers and Watson 1993). While the sedimentation rate is relatively high in cave entrances, in deep caves it is exceedingly slow (there are catastrophic exceptions, but these generally oc curred before human occupation in the Americas), making the identification and interpretation f artifact palimpsests difficult. Stratigraphie distinctions become valid when the paleosurface is disturbed, typically due to prehistoric and historic human activity, which can result in the inundation of paleosurfaces and associ ated archaeological materials. In an arrested cave, prehistoric and recent distur bances are distinguished at the surface primarily by the presence of cave pa tina. Cave patina is a colloquial term that generally refers to a thin, dark crust This content downloaded from 128.197.26.12 on Tue, 10 Jun 2014 20:55:05 PMAll use subject to JSTOR Terms and Conditions
