The black mat at the Water Canyon Paleoindian site near Socorro, New Mexico: A paleoenvironmental proxy data archive for the Pleistocene-Holocene transition

Abstract

The Water Canyon Paleoindian site near Socorro, New Mexico, is directly associated with an extensive buried wetland deposit, or black mat. This landscape-scale feature, which was extant across the late Pleistocene–early Holocene transition, represents the remains of a wetland resource that, during the early Holocene, may have served as an ecological refugium for flora, fauna and Paleoindian groups as other regional water sources disappeared. Today the organic-rich deposit has proved to be an important proxy data archive for environmental, climatic and archaeological reconstructions. Our recent paleoenvironmental reconstruction efforts at the site have focused largely on the period from ~8300 to 11,100 radiocarbon years ago, and have generated a range of proxy data, including dated pollen profiles, stable carbon isotope values, charcoal species identifications, and both faunal and macrobotanical remains. The pollen data currently provide the most robust basis for our paleoenvironmental reconstruction and, together with our chronometric data, affirm that the black-mat forming wetland served as a persistent place of ecological diversity. These findings provide us with provocative glimpses of past environments in a heretofore largely understudied region of the American Southwest, and add to a growing body of Southwest reconstructions that will ultimately enable researchers to compare paleoenvironments and paleoclimates at both local and regional scales. 491