Geochemical comparisons of silicified rhyolites from two prehistoric quarries and 11 prehistoric projectile points, Socorro County, New Mexico, U.S.A.

Abstract

This paper documents the results of nondestructive X-ray fluorescence (XRF) geochemical analyses and comparisons of silicified rhyolites from the Black Canyon and Sedillo Hill prehistoric quarries near Socorro, New Mexico, and subsequent comparisons of the quarry rhyolites with 11 temporally diagnostic projectile points. At the current level of analysis, findings indicate that (1) the two quarries are chemically distinct and (2) the lithic materials of two projectile points match the silicified rhyolite from the Black Canyon quarry, suggesting quarry use during the Early Archaic period (4800-3200 B.C.) and the Late Archaic period (1800-800 B.C.). A close match between the Black Canyon rhyolite and one other point provides tentative support for use of the quarry during the Clovis Paleoindian period (9500-9000 B.C.). Additional geochemical analyses of the two quarries and other regional sources should be undertaken to verify these results and further expand our understanding of prehistoric mobility in the Southwest. ᭧

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