ABSTRACT: Prolific Upper Pleistocene Gas Sands: Southeastern High Island and Southern West Cameron Additions, Offshore Northern Gulf of Mexico
DAWSON, BRUCE W., JEFFERY E. LARSON, EDWARD C. MCCLINTOCK, MICHAEL D. TAYLOR, and AMY B. THOMPSON
Recent discoveries by Burlington Resources in the Southeastern High Island and the Southern West Cameron Additions, offshore Texas and Louisiana, have confirmed the presence of thick, stacked Upper Pleistocene gas sand reservoirs. These new fields are located in High Island block A371 and West Cameron block 635, in water depths ranging from 380 to 400 feet. Production from the two largest reservoirs at High Island block A371 has been sustained at rates exceeding 45 million cubic feet of gas per day per completion.
Lowstand shelf-edge deltas deposited sands from 850,000 to 400,000 years ago within an east-west oriented graben system near the present-day shelf edge. Syndepositional salt movement resulted in the accumulation of thick, high quality Upper Pleistocene reservoirs within the graben and the development of hydrocarbon traps via structural uplifts and associated faulting.
Three-dimensional seismic interpretation was a key factor in the successful drilling of both gas fields. All known gas reservoirs in the study area exhibit strong amplitude response on three dimensional seismic data sets. These amplitudes commonly conform to the areal extents of the gas reservoirs. Gas/water contacts are often identifiable from flat spots on the seismic data. Deltaic channel axes are also recognizable with the implementation of coherency technology.
Geoscience and engineering teamwork allowed quick development of the High Island A371 field. The high percentage of drilling success combined with high volume gas completions have resulted in a project with superior economic value.
AAPG Search and Discovery Article #90941©1997 GCAGS 47th Annual Meeting, New Orleans, Louisiana