Datapages, Inc.Print this page

Development of a Paleogene Canopy System and Associated Rafts, West-Central Deepwater Gulf of Mexico

Liro, Louis M.1; Lytton, Rome 2; Holdaway, Steve 1; Carlson, Thomas 1; Loera, Daniel 1; Hannah, Tyler 1
1 North America Exploration and Production, Chevron, Houston, TX.
2 Energy Technology Company, Chevron, Houston, TX.

Canopy salt in the Garden Banks / Keathley Canyon area typically overlay interpreted Oligocene-upper Eocene strata, indicating that this was the age of emplacement of a large regional canopy system in the subject area. This contrasts with the younger, generally Miocene, canopy emplacement in the east-central deepwater Gulf of Mexico.

Examination of the Paleogene canopy system reveals numerous rafts of lower Tertiary and Mesozoic strata preserved above the canopy. Norton (GB 754) and Vienna (GB 840) documented these rafts; reflection seismic data reveal many more probable rafts of similar seismic signature but uncertain age. These rafts originated as in-place strata deposited above autotchonous salt; subsequent canopy development dissected these roof rocks and transported them during allochthon expansion.

Sumatra (GB 941) penetrated subsalt section including blocks of upright and overturned Miocene overlying an intact Eocene-to-Mesozoic raft. This raft, originally on the Paleogene canopy, docked onto normal Oligocene section as the canopy deflated to a weld.

Examination of regional reflection seismic data reveals that the Sumatra salt weld can be correlated to intact Paleogene canopy, confirming the contemporaneous emplacement age and allowing better understanding of the emplacement and deformation history of the Paleogene canopy system.

 

AAPG Search and Discovery Article #90090©2009 AAPG Annual Convention and Exhibition, Denver, Colorado, June 7-10, 2009