The proposed research is an investigation of the late Quaternary paleoenvironmental record preserved in the small playa basins on the Southern High Plains of northwestern Texas and eastern New Mexico. The goals of this project are to better understand: 1) cool-dry environments evolving into cool-moist ones in the late Pleistocene; 2) rapid and repeated shifts between cool-moist and warm-dry environments in the last millennia of the Pleistocene and early millennia of the Holocene; 3) the rate and timing of the environmental changes that resulted in the relatively dry and warm climate that characterized much of the early and middle Holocene; and 4) rapid and repeated environmental departures toward aridity in the past few millennia of the Holocene. Preliminary investigations of playa fills indicate that they have dateable, continuous records of sedimentation spanning the late Quaternary, and that they contain paleoenvironmental indicators in the form of the sediments themselves, and also stable-carbon isotopes and phytoliths. The work collected in the field. The research will provide clues to the age and origin of a significant component of the Great Plains landscape. More specifically, the studies will help in understanding the late Quaternary evolution of the environment of the Southern High Plains, a region known to be sensitive to environmental changes, the regional significance of environmental fluctuations, and the response of the High Plains landscape to these shifts. The proposed research, therefore, will complement and, more importantly, strengthen and significantly expand the late-Quaternary paleoenvironmental record of landscape evolution and response to environmental change
