Geoarchaeology of the Boca Negra Wash Area, Albuquerque Basin, New Mexico, USA

Abstract

Dozens of Paleoindian sites, including the Boca Negra Wash (BNW) Folsom site (LA 124474), are scattered across a basalt plateau (the West Mesa) on the western side of the Albuquerque Basin, and adjacent uplands. The BNW site, like many others in the area, is located near a small (~60 ϫ 90 m) playa basin that formed in a depression on the basalt surface and was subsequently covered by an eolian sand sheet (Unit 1) dated by OSL to ~23,000 yr B.P. Most of the basin fill is ~2 m of playa mud (Units 2 and 3) dating ~13,970 14 C yr B.P. (17,160-16,140 cal yr B.P.) at the sand-mud interface to ~2810 14 C yr B.P. (~2960-2860 cal yr B.P.) at the top. C/N ratios suggest that the BNW playa basin probably held water more often during the Folsom occupation; stable carbon isotope values indicate C3 vegetation was more common as well, but C4 grasses became dominant in the Holocene. Cores extracted from four playa basins nearby revealed a similar stratigraphy and geochronology, documenting presence of wetlands on playa floors during the Paleoindian occupation of the area.

Spatiotemporal dynamics of the Clovis–Folsom transition

“…Currently, securely dated Folsom sites occur only in the Great Plains and Rocky Mountains. However, there are Folsom sites in several other regions that are, as yet, undated (Amick, 1994;Holliday et al, 2006;Judge, 1973). As far as assessing the validity of the findings of the study reported here are concerned, the Folsom sites of the Rio Grande Valley would be a particularly good focus of a dating project.…”

Impacts of climate change on the formation and stability of late Quaternary sand sheets and falling dunes, Black Mesa region, southern Colorado Plateau, USA

“…Instead, topographically controlled dunes were formed with increased sediment supply and wind-transport capacity during the late Pleistocene (MIS 3 and 2). The few studies that document pre-Holocene eolian deposits in Arizona and New Mexico also show that the largest amount of currently stabilized sand was deposited during the late Pleistocene (Wells et al, 1990;Reheis et al, 2005;Holliday et al, 2006).…”

Geochronology of the Bolson sand sheet, New Mexico and Texas, and its archaeological significance

“…Other successful OSL studies of eolian sand have been conducted in the region ( Fig. 3) (Hall, 2002;Hall and Goble, 2006;Holliday et al, 2006).…”

“…However, deposition of the eolian cover sand on the West Mesa near Albuquerque generally occurred during the late Pleistocene, within the period of deposition of Q3 sand in the Bolson sand sheet (Fig. 3) (Holliday et al, 2006;. Overall, a high-resolution geo chronology of the various eolian deposits that would allow correlation across the continent from one region to another is in its infancy.…”

“…Thin sand sheets are known to accumulate at a rate less than 0.3 mm/yr. Regional examples are the Mescalero Plain of southeastern New Mexico (Hall and Goble, 2006;Raymond et al, 2007) and the small area of cover sand on the West Mesa near Albuquerque Holliday et al, 2006) ( Table 5). The sand sheets have sedimentation rates similar to that of late Quaternary loess from the Great Plains (Rousseau et al, 2007;Mason et al, 2008), although the loess sequences include buried soils, while the cover sands mentioned here do not have buried soils.…”