Print this pageBasement Controls from the Distribution and Geometry of Salt Structures in the Central-Eastern Gulf of Mexico
Structural analysis of the central-eastern Gulf of Mexico (GOM) protraction areas was accomplished by integrating seismic reflection data and gravimetric/magnetic field data to better understand the basement configuration in relation to salt geometry and kinematics. The original Jurassic rift architecture controlled the distribution of the autochthonous Louann salt and subsequent emplacement of the allochthonous salt systems. Tertiary and modern depositional systems also appear to have been influenced by the structural configuration of the basement and by the salt distribution.
Basement faults in the GOM delineate a series of horst, grabens and half grabens prevalently northeast-southwest oriented offset by northwest-southeast trending transfer fault zones. Salt structures presented in the GOM have been originally initiated in proximity of basement features, where differential sediment loading was controlled by differential initial salt thickness. A significant number of salt bodies show characteristics of vertical salt movement above basement highs and are allined with northwest-southeast trending transfer fault zones.
In this portion of the GOM, the regular spacing and offset of transfer zones, the related salt bodies, and the arrangement of the rift related structures, can be used as a template to understand the complex interaction between tectonics and sedimentation in poorly imaged areas beneath thick allochthonous salt bodies. Understanding the regional tectonic setting and basement influences/behaviour, are critical elements in prospect risk assessment and also can indicate the most favorable areas for exploration.
AAPG Search and Discover Article #90100©2009 AAPG International Conference and Exhibition 15-18 November 2009, Rio de Janeiro, Brazil