Fluid Compartmentalization and C02 Sequestration Potential of Bay Marchand Salt Dome, Offshore Louisiana

Steen, Andrew K.¹; Nunn, Jeffrey A.^1
1 Geology and Geophysics, Louisiana State University, Baton Rouge, LA.

Bay Marchand Salt Dome which straddles the coastline in Southwest Louisiana has significant potential as a site for CO2 sequestration because it contains saline reservoirs, has an extensive existing infrastructure of wells and pipeline and abundant subsurface data exists. 3-D seismic data and well logs provide a structural and stratigraphic framework for the field. Previous studies in Bay Marchand and elsewhere have shown that information on the subsurface distribution of fluid pressure, temperature, and salinity derived from well logs and geochemical analysis can be used to infer vertical and lateral connectivity of reservoirs and to predict fluid flow pathways and rates. This includes changes in salinity across faults, which indicate fluid compartmentalization and the role of faults as barriers or conduits to fluid flow. A previous study on Bay Marchand by Bruno and Hanor (2003) showed variations in temperature and salinity that are consistent with downward migration of sea water along growth faults near the top of the dome. Adequate seal capacity in these faulted reservoirs is critical to their potential as sequestration sites. The south flank of the dome is the least faulted area of the dome and thus is the primary focus of this research.

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