The emerging Paleogene play: Deepwater Gulf of Mexico

摘要

The Paleogene Wilcox trend has emerged as an important frontier play in the deepwater Gulf of Mexico, as confirmed by several recent discoveries. The Wilcox trend is an onshore prolific producer along the Gulf Coast region, but its potential in deepwater settings has been recently recognized.At Repsol, a regional evaluation of the Wilcox depositional system was conducted using 2D seismic data sets and limited 3D surveys available from the western and central areas in the Gulf of Mexico. Most of the area is characterized by the presence of allochthonous salt, thus, seismic imaging is generally poor. Mapping of both Upper and Lower Wilcox sequences of more than 35,000 square miles indicate a widespread distribution for the Wilcox strata. These anomalously thick and extensive sedimentary deposits extend 200 miles downdip from the paleoshelf edge. Wilcox age-equivalent paleocanyons have been previously recognized and mapped along the Gulf coast, and they could have been the conduits for sediment transport and dispersal into the deepwater depositional environments.The Lower Wilcox records sand deposition in amalgamated channel a basin floor setting, whereas the Upper Wilcox seems to represent channelized sands in a slope setting. The deepwater interpretation was linked updip to the shelf area, and downdip into the abyssal plain to better understand the entire Wilcox depositional system. Regional isopachs shows the major depocenters and three major source areas in Texas and Louisiana. The western Gulf of Mexico areas were sourced from the Rio Grande and the Houston Embayment. The Eastern Keathley Canyon and Walker Ridge areas were sourced from Louisiana, via the ancestral Mississippi River.