Abstract

Study of well logs, cores, and seismic data in the Kingdom Field area and other parts of the Abo Shelf Complex trend in New Mexico and Texas has led to new concepts about the style of deposition and 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 resulted in the recognition of four depositional facies that have significant control on reservoir character. These facies are: Supratidal/Terrestrial (updip and top seal), Intertidal (reservoir grainstones), Lagoonal (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 3-D seismic data shows that at least three third-order sequence boundaries, associated with subaerial exposure of the shelf and significant karstification, are intraformational in nature.