Bureau of Economic Geology, The University of Texas at Austin (www.beg.utexas.edu).
American Association of Petroleum Geologists Annual Meeting, Dallas, April 18-21, 2004
Geologic Controls on Neogene Deep-Water and Shelf Gas Plays, Laguna Madre-Tuxpan Continental Shelf, Eastern Mexico
William A. Ambrose, Tim F. Wawrzyniec, Khaled Fouad, L. F. Brown, Shinichi Sakurai, David C. Jennette, Edgar H. Guevara, Mario Aranda Garcia, Ulises Hernández Romano, Ramón Cárdenas Hernández, Eduardo Macías Zamora, and Suhas C. Talukdar
Neogene deltaic, slope-fan, and basin-floor-fan depocenters in the Laguna Madre-Tuxpan continental shelf were controlled by a variety of structural and physiographic elements reflecting strike-slip motion, gravity sliding and extension, uplift of source terrains, and salt evacuation. In a 16-month study of the eastern Mexico continental shelf, conducted jointly by the Bureau of Economic Geology (BEG) at The University of Texas at Austin and PEMEX Exploración y Producción, more than 30 plays were defined and mapped over a 50,000-km2 area linking the Veracruz and southern Burgos Basins.
The south part of the area, structurally continuous with the Veracruz Basin, contains several deep-seated basement faults that influenced depositional patterns of middle Miocene deepwater canyons, slope fans, and basin-floor fans that extend for tens of kilometers into the deep offshore. A major downdip structural trend occurs east of major listric faults and gravity-sliding systems north of the Veracruz Basin. Long-term, intermittent growth fault movement provided subsidence and accommodation sufficient to stabilize Pliocene shelf edges, resulting in hundreds of meters of aggradational, stacked deltaic and shoreface deposits. The north end of the area, part of the Burgos Basin, contains intensely deformed strata associated with active and passive diapirism, salt withdrawal, and salt welds. Upper Miocene and Pliocene plays in this area are mud-rich and internally complex, including debris-flow and canyon-fill deposits. The upper Pliocene and lower Pleistocene are dominated by chaotic successions of muddy slump and slope-channel deposits reflecting massive failure of muddy, unstable slopes.