New Views on Salt Tectonics and Salt Modeling Using the Latest Seismic Imaging Technologies, for Subsalt and Presalt Exploration in the Mississippi Canyon, Gulf of Mexico
Quincy Zhang, Wei Gao, Laurie Geiger, Steve Hightower, Cristina Reta-Tang, and Sherry Yang
Subsalt and pre-salt seismic imaging have always been a major challenge for exploration in the Mississippi Canyon (MC) area of the Gulf of Mexico. Recently, interpreters' ability to build high-quality salt models has been greatly improved with the newly acquired Wide Azimuth (WAZ) and orthogonal WAZ data, the latest processing technology and computing capacity, a specially designed workflow based on the regional geology and salt tectonics, and specific interpretation tools for the integration of all available data. Due to the unique double-hourglass shape of salt in MC, three-salt-body-model methodology is applied for building salt models in MC: Salt Body 1 to define salt canopy in the shallow, Salt Body 2 to define salt feeders in the middle and Salt Body 3 to define autochthonous salt in the deep. In every Salt Body, there could be several small overhangs, which represent major changes in salt-sediment interactions and need more iterations to define in local areas. Here we present two examples to show that the new seismic images represent real geology very well and are distinguished data for subsalt exploration. The first example shows that underneath the main canopy several salt wings and a nearly vertical and overturned salt feeder are well imaged and the second example shows that two plays have been completely separated by a salt wall since the Jurassic. We conclude that the new salt model has significantly improved the seismic image and has greatly reduced exploration risk.
AAPG Search and Discovery Article #90167©2013 GCAGS and GCSSEPM 63rd Annual Convention, New Orleans, Louisiana, October 6-8, 2013