AAPG ANNUAL CONFERENCE AND EXHIBITION
Making the Next Giant Leap in Geosciences
April 10-13, 2011, Houston, Texas, USA
Sediment Redistribution in the Gulf of Mexico Resulting from the K/Pg Boundary Chixculub Impact and the Resulting Influence on Wilcox Formation Sedimentation Patterns
(1) Marathon Oil Company, Houston, TX.
The Chicxulub impact has been cited as the cause to re-mobilized sediment into a mass transport flow on the submerged shelf along eastern North and Central America as well as around the Gulf of Mexico and redistributed it out into the deep water Gulf of Mexico, Atlantic and Caribbean (e.g. the 150 m thick K/Pg deposit in the Penalver Formation near Havana, Cuba). Examination of log and biostratigraphic data from 16 Cretaceous well penetrations by industry in the deep-water northern Gulf of Mexico identified a distinctive micritic deposit ranging from 10 to 200 m (30-600') in thickness at the K/Pg boundary that is similar in composition to sediments found near the Chicxulub Crater. When the Chicxulub impact occurred the northern Gulf of Mexico was undergoing allocthonous salt movement from the Jurassic aged Louann Salt that was expressed in numerous salt ridges establishing clastic sediment fairways that funneled sediment input from the shelf into the deep water. This mass transport deposit caused by the Chicxulub impact did not completely cover all these salt ridges but filled in the available accommodation space, as seen in the varying thicknesses of the well penetrations, and created a new base level across the northern Gulf of Mexico. The overlying clastic sediments of the Paleogene/Eocene aged Wilcox Fm. continued to be funneled down the still existing fairways partially filled in by the mass transport deposits as defined by the salt ridges. As the sediment gravity flows exited these corridors they formed coalescing distributary complexes across the new Gulf of Mexico wide base level.