Abstract: Economic Potential of Canyon-Fan Unit in Anadarko Basin, Oklahoma

Jeff A. Tassone, Glenn S. Visher

The Cunningham sandstone (Springer) can be interpreted as an inner canyon-fan deposit in the Anadarko basin in Oklahoma. Integrated subsurface methods including sedimentary structure analysis, subsurface mapping techniques, log motifs, and paleogeographic patterns were used to interpret the depositional environment.

The sandstone was deposited in a restricted area with onlap occurring across the continental slope. The source of clastic material was from erosion of Chester and older rocks present on the northeast margin of the basin. Later erosion and truncation reflected by Morrowan strata obscure submarine-canyon deposits, but inner canyon-fan deposits are preserved in the Anadarko basin. Cross sections illustrate both truncation and updip onlap of the Cunningham sandstone.

Sedimentary structures from the Cunningham sandstone exhibit a variety of mass- and fluid-flow characteristics. Log motifs show a blocky pattern with sharp basal contacts. Thin alternating sandstones and shales are present in interchannel areas. Sandstone geometry illustrates inner channel-fan patterns. In cross sections depocenters are indicated by a convex-upward bulge in areas where stacking of channels has occurred.

Morrow-Springer sandstone deposits in the Anadarko basin are economically important. Gas reserves in these units approximate 20 Tcf. Traps are generally stratigraphic, but with updip truncations and depositional pinchouts. Other Springer sandstones similar to the Cunningham are important exploration objectives within the Anadarko basin and in similar tectonic basins and borderlands.

AAPG Search and Discovery Article #90961©1978 AAPG Annual Convention and Exhibition, Oklahoma City, Oklahoma