Depositional Models and Resource Potential of Pennsylvanian System, Palo Duro Basin, Panhandle Texas: ABSTRACT

Abstract

The Palo Duro basin of the Texas Panhandle is a relatively sparsely drilled interior basin. Sediments of Pennsylvanian age were deposited in a variety of clastic and carbonate environments. From 0 to 2,400 ft (0 to 732 m) of sediment was deposited with greatest accumulation along a northwest- to southeast-trending basin axis. Erosion of Precambrian basement in the Amarillo and Sierra Grande uplifts supplied arkosic sand and gravel to alluvial fans and fan deltas along the northern margin of the basin. Distal-fan sandstones are interbedded with thin shelf limestones, and basinward of clastic deposition, shallow-shelf limestone was deposited across most of the Palo Duro basin. Basinal shales were deposited only in a small area just north of the Matador arch. Increased subsidence deepened and enlarged the basin throughout the Late Pennsylvanian. Ultimately, the basin axis trended east-west with a narrow northwest extension. A carbonate-shelf-margin complex with 200 to 400 ft (70 to 120 m) of depositional relief developed. High-constructive elongate deltas prograded into the Palo Duro basin from the east in the Late Pennsylvanian. Prodelta mud and sands entered the basin through breaks in the carbonate-shelf margin. Porous dolomitized limestone is present in belts 10 to 20 mi (16 to 32 km) wide along the shelf edge. Potential hydrocarbon reservoirs are the dolomitized limestone, fan-delta sandstones, and deltaic bar-finger sandstones. However, the thermal history of the basin may not have allowed hydrocarbons to mature or migrate into reservoir facies. End_of_Article - Last_Page 1425------------