ABSTRACT: Provenance of the Delaware Mountain Sandstone Group of the Delaware Basin, Texas and New Mexico

BASHAM, WILLIAM L.

It is difficult to account for the enormous volume of siliciclastics in the Delaware Basin which is surrounded by platform carbonates. Introduction of sands are believed to have occurred at sea-level lowstands across karst surfaces in the lower Delaware, Mountain Group and along the numerous thin shelf sand beds in the upper Delaware Mountain Group.

Regional maps of the Pennsylvanian-Permian basement uplifts, Leonardian sediment distribution, Glorieta Sandstone extent and composition, and San Andres Formation distribution were useful in search of arkose sources for the Delaware Mountain Group sandstones.

Progressive clockwise fanning of Delaware channel directions from ESE for the Brushy Canyon to SSW for the Bell Canyon Formation is documented. This fanning may be related to a continual change in wind direction and possible easterly shift in sediment source location. However, similar heavy mineral suites in the Brushy Canyon, Cherry Canyon, and Bell Canyon sandstones suggest that they all had the same general source.

The Shattuck (shelf equivalent of the basinal Cherry Canyon Fonnation) sands are more arkosic and are coarser than the basinal sand. The shelf Glorieta Sandstone also is coarser than the Delaware sands but is less arkosic than the basinal sand.

Calculation of Delaware Basin siliciclastic volume and comparison to possible arkosic source areas leads to the conclusion that most of the sediment probably came from the ancestral Front Range in Colorado. Other areas, such as the Pedernal and Sierra Grande Mountains of New Mexico, Wichita mountains of Oklahoma, and the Llano Uplift of Texas probably also contributed arkose to the Delaware Basin but in much less total volume.

AAPG Search and Discovery Article #90947©1997 AAPG Southwest Section Meeting, San Angelo, Texas