8 Rancholabrean Paleoecology of Western North America

Wednesday, 19 March 2008
1:30 PM - 5:00 PM

TAPHONOMY OF THE GILCREASE SPRING MOUND PALEONTOLOGICAL SITE, CLARK COUNTY, NEVADA

Paper number: 8-8
Program: THEME SESSIONS
Time: 3:40 PM – 4:00 PM

Authors

Abstract

Discovery of fossils at the Gilcrease Ranch and Bird Sanctuary in 1985, has led to a diverse faunal assemblage from the late Pleistocene. This site is currently being excavated by the Nevada Friends of Paleontology Society as a joint project. The site is associated with a now dry artesian spring mound. The majority of recovered fossil material consists of mammal tooth elements. The most numerous taxon recovered is Mammuthus; other taxa recovered include Equus, Bison, and Camelops. Radiocarbon dates on material from this site yield ages of 21ka to 13ka.

Bone recovered from the site is highly fragmentary and unidentifiable to any specific taxon. Tooth elements are found intact in some cases and highly fractured in others. No elements are articulated and none can be confidently said to be associated. This is presumably due to churning within the spring.

The stratigraphy of the site includes a basal pebble conglomerate which is overlain by a very fine sandstone with interbedded silty mudrock horizons. The basal pebble conglomerate has yielded the most fossil material as well as some cultural material. A taphonomic study of this quarry has never been performed and can lead to some potentially vital information regarding the ecology of Las Vegas Valley during the Late Pleistocene.