Facies and Sequence Stratigraphy of the Abo Formation in the Kingdom Field Area, Terry and Hockley Counties, West Texas
Anthony E. D’Agostino, OMNI Labs Inc., Houston, Texas
J. Michael Party, Wagner, & Brown, Ltd., Midland, Texas
Study of conventional cores, well logs, and seismic data in the Kingdom Field and other parts of the Abo shelf complex trend in eastern New Mexico and west Texas has led to new concepts about the style of deposition and techniques for stratigraphic subdivision of the Leonardian Abo Formation. The implications of paleogeographic restoration of the Abo shelf, combined with detailed description and interpretation of conventional cores from nine wells in Kingdom Field has resulted in the identification of four important depositional facies that have significant control on reservoir character. The facies are; Supratidal/Terrestrial (up-dip and top seal), Intertidal (reservoir grainstones), Platform Interior (reservoir barrier), and Shelf-edge (secondary reservoir). A fifth facies, Karst Breccia, is also defined. This study reveals that the most productive facies in Kingdom Field (and along the trend) is the intertidal facies (peloid grainstones) not the shelf-edge facies (boundstone reef). High-resolution stratigraphic analysis combining Fischer plots, well-log cross-sections, and 3D seismic data shows that at least three third-order sequence boundaries, associated with exposure of the shelf and significant karsting, are intraformational in nature.