Desmoinesian Depositional Systems in Knox-Baylor Trough: ABSTRACT

Abstract

The western part of north-central Texas experienced unique depositional processes during the late Desmoinesian. The early Desmoinesian-Fort Worth basin depocenter was moved toward the west after the Ouachita overthrust. Sediments were carried westward to the resultant Midland basin through the Knox-Baylor trough. This asymmetric trough (steep on the north) possesses two distinct depositional systems. The south or Concho platform flank has a wave-dominated environment with strike-oriented strand-plain and deltaic sands similar to the upper Wilcox sands of the Gulf Coast. This system is present in Baylor, Knox, Throckmorton, and Haskell Counties. Some of the producing areas are in the Sojourner, Herren, and Weinert fields. The deep-water environment holds low-flow-regime deposits. They are ripple bedded, lack bioturbation, and are strike oriented. A study of the composition demonstrates well-sorted, clean, fine-grained bodies which indicate significant reworking during long-distance transport. This system extends from northern Knox County southwest through Stonewall County and produces in such fields as the Anne Tandy, Katz, Juliana, and Jud, the most desirable oil fields in the area. End_of_Article - Last_Page 2116------------