Pliocene and Quaternary Deposits in the Northern Part of the San Juan Basin in Southwestern Colorado and Northwestern New Mexico:Scientific investigations rept

摘要

Pliocene and Quaternary deposits were studied near Durango, Colorado, in April and May of 1977, in company at different times with Donald A. Coates, John D. Strobell, and Juanita M. Scott. As a result of reconnaissance mapping, study of soils, geomorphic and stratigraphic positions of deposits, measurement of stratigraphic sections, pebble counts, and collection of volcanic ash beds (later identification by Glen A. Izett), a sequence of deposits was established. This sequence includes alluvial, loess, eolian sand, landslide, till, and outwash deposits ranging in age from Pliocene (Blancan) to latest Holocene. The terms Bull Lake and Pinedale are used here in a general time sense and are not intended to imply exact contemporaneity or correlation with Bull Lake and Pinedale deposits in the type areas in Wyoming.