Provenance Analysis of Obsidian from Two Late Prehistoric Archaeological Sites in Kansas

Abstract

Six obsidian artifacts from two protohistoric archaeological sites in Kansas were subjected to non-destructive energy dispersive x-ray fluorescence analysis to determine the parent obsidian source used in their manufacture. Results indicate all six specimens were derived from two obsidian sources located in the Jemez volcanic field of northern New Mexico. Silicic volcanic glass (obsidian) are well known from various parts of the Far West, and for the last two decades x-ray fluorescence and neutron activation analysis have been employed by geochemists and archaeologists to determine the parent source of origin for artifacts recovered from prehistoric archaeological sites. Such research has been conducted intensively in California (Jack, 1976; Ericson, 1981; Hughes, 1986) and the Great Basin (Hughes, 1983, 1985; Hughes and Bennyhoff, 1986). Despite the relative paucity of obsidian samples, some important research along these same lines has been undertaken in the Midwest and Plains (Anderson et al., 1986; Frison et al., 1968; Griffin et al., 1969; Baugh and Nelson, 1987, 1988). Baugh and Nelson (1987) for example, have identified changes in the amounts and sources of obsidian used in several southern Plains archaeological sites, and have advanced hypotheses to account for observed changes. One of the more conspicuous gaps in current understandings about prehistoric obsidian conveyance in the Plains concerns Kansas archaeological sites. Although archaeological obsidian was first noted in Kansas over a century ago (Putnam, 1880), it wasn't until the systematic fieldwork of Waldo Wedel between 1937-1940 the presence of obsidian in the state became known to a wider audience of professional archaeologists. Despite the distance from sources of volcanic glass, a surprising amount of obsidian has been documented from Kansas sites. Wedel (1959, pp. 265, 314, 335, 367This content downloaded from 207.46.13.128 on Tue, 06 Sep 2016 06:08:34 UTC All use subject to http://about.jstor.org/terms VOLUME 94, NUMBERS 1-2 39 368, 411, 545), for example, reported more than 80 obsidian artifacts (mostly flakes) from seven sites in Kansas. Since then, obsidian has been a common, if low frequency, find on Kansas sites, particularly on Late Ceramic period (post AD 1500) sites associated with the Great Bend aspect (protohistoric Wichita) in Rice County. At least thirty years ago Wedel speculated obsidian from the central and northern Plains was obtained from Obsidian Cliffs, Wyoming, but that in sites from the Republican Valley southward is more likely from New Mexico or Colorado deposits (Wedel, 1961, p. 274; cf. 1959, p. 264). Although not using Kansas data, Baugh and Nelson (1987) recently observed prior to AD 1450 obsidian found in Southern Plains sites originated from in New Mexico, Idaho, and west-central Utah but after AD 1450, obsidian was derived exclusively from New Mexico. Baugh and Nelson (1987) thus postulated a major change in exchange relationships from north-south to an east-west orientation to account for this change in source use. The present study places both models of Wedel, and Baugh and Nelson to empirical test through analyses of a sample of artifacts from two archaeological sites in the Southern Plains in Marion and Comanche counties, Kansas (see Fig. 1). The two samples analyzed from Marion County come from the Mem site (14MN328), a Great Bend aspect (protohistoric Wichita) site excavated in 1986 in conjunction with a highway salvage project. As of this writing, these specimens are the only obsidian artifacts recovered from this, or any other, Great Bend site in Marion County (Lees et al., 1989; Rohn and Emerson, 1984). Sample 20599 was recovered from the upper levels of a large cache (storage) pit and was associated with European-made artifacts, one of which was a glass bead dated to around AD 1700 (Lees, 1990a). The other sample (10128) was recovered unassociated in the 0-30 cm level of the site. The four samples from Comanche County were excavated from the Booth site (14CM406) during 1989 research by the Kansas State Historical Society and the Kansas Anthropological Association (Lees and Reynolds, 1989). Obsidian made up about 5 percent of the entire chipped stone inventory at the Booth site, an unusually high percentage for Kansas and the Plains in general. Recent chronological information from the Booth site indicates a Late Ceramic period affiliation (suggesting contemporaneity with the Mem site), although the possibility of an earlier occupation during the late prehistoric Middle Ceramic period (AD 1000-1500) also exists. The identity of the Native American occupants of this site is, however, not currently known (Lees, 1990b). METHODS AND PROCEDURES Laboratory analyses on these samples were performed on a Spectrace 5000 (Tracor X-ray) energy dispersive x-ray fluorescence spectrometer This content downloaded from 207.46.13.128 on Tue, 06 Sep 2016 06:08:34 UTC All use subject to http://about.jstor.org/terms 40 TRANSACTIONS OF THE KANSAS ACADEMY OF SCIENCE Cerro KANSAS del Medio