Hydrocarbon Production and Exploration of the Distal Frio Formation, Texas Gulf Coast and Offshore

Along the Texas Gulf shoreline and offshore, the distal margin of the Frio Formation is a deep hydrocarbon province that is underexplored relative to the onshore Frio. Thick shelf and slope mudstones constitute most of the distal Frio, but deltaic, barrier/strandplain, shelf, and slope sandstones also occur, some of which are good reservoirs and established producers. Production and reservoir-quality trends, temperature and pressure conditions, and field characterizations were integrated with the regional stratigraphic and structural framework to evaluate the potential for further exploration and development and to outline optimal fairways for distal Frio exploration offshore. Distal Frio exploration potential is greatest in the Mustang Island and northeastern Galveston offshore areas, where porous and permeable sandstones coincide with appropriate structures and seals. New-field discoveries will be deep, overpressured, gasprone reservoirs; most will be small and relatively short-lived. However, data reviewed during this study indicate that a few intermediate to large distal Frio fields await discovery.