Significant Test Results, Energy Potential, and Geology of Some Gulf Coast Geopressured-Geothermal Sandstone Reservoirs: ABSTRACT

Abstract

Geopressured-geothermal reservoir found in the northern Gulf of Mexico basin represent a large potential future energy resource. Three reservoirs in various stages of developmental testing are of current interest. Over a four-year testing period the Gladys McCall 1 (Cameron Parish, Louisiana) produced 27.3 million bbl of brine and 676 million scf of gas at an average rate of 20,000 bbl/day from perforations between 15,158 and 15,490 ft. This lower Miocene sandstone section forms part of a genetic unit of interconnected channel and point-bar sandstones deposited in a lower shelf environment. Pleasant Bayou 2 well (Brazoria County, Texas) is currently being flow-tested at 20,000 bbl/day and has a gas/brine ratio of approximately 23 scf/stb and a temperature of 291/degrees/F. An electric energy conversion system being set up here will test potential for electric generation from geopressured-geothermal energy. Superior Hulin 1 (Vermilion Parish, Louisiana) is a deep (21,549 ft) former gas well proposed to be completed as a geopressured-geothermal well. Initial log analysis indicates that a 570-ft thick sandstone, of probable submarine fan origin, may contain free gas in addition to solution gas and may thus represent an economically feasible geopressured-geothermal well. Gas-separated brine is disposed by subsurface injection into disposal wells.more » However, in areas where hydrocarbon fields with wells penetrating geopressured sands are present, hot brines could be injected into depleted hydrocarbon zones to aid secondary recovery.« less