PALEOINDIAN BASALT AND OBSIDIAN SOURCES IN THE NORTH AMERICAN SOUTHWEST: A PRELIMINARY MODEL OF LATE PALEOINDIAN TERRITORIALITY

Recent analytical chemical analyses of Late Paleoindian and Early Archaic basalt and obsidian artifacts recovered from sites in central New Mexico to southern Colorado indicate differential procurement of both materials suggesting differing procurement ranges and probably territories. This appears to be distinct from the procurement of secondary siliceous sediments such as chert and jasper, which are distributed throughout the region irregardless of territories or location. While the obsidian sources used during these time periods have been well known for years, the two dominant fine-grained basalt sources have only recently been discovered. Cerros del Rios on Bandelier National Monument near the Rio Grande River, and Mount San Antonio in northern New Mexico, are virtually the only mafic volcanics used to produced chipped stone tools during this period, likely due to the extremely rare fine grained fabric.

The obsidian procured is dominated by El Rechuelos and Valle Grande Rhyolite in the Jemez Mountains of northern New Mexico. Cerro Toledo Rhyolite glass, while present in minor proportions, does not dominate the assemblages. Those Folsom sites south of the Jemez Mountains exhibit Valle Grande Rhyolite glass almost exclusively, while those sites north of the Jemez exhibit El Rechuelos obsidian almost exclusively. The basalt sources are similarly distributed north-south, and taken together suggest territoriality at least with respect to these two toolstone sources. The chert and jasper sources found in these sites do not fit this pattern which suggest differing attitudes about raw materials in the Late Paleoindian and Early Archaic periods, an idea not new, but potentially substantiated by this new evidence. Whether this signals territoriality during these early periods of prehistory in the northern Southwest similar to that suggested in the Great Basin, is worthy of discussion at this point.