The Effects of Provenance and Burial History on the Reservoir Quality of Clastic Sediments in the Gulf of Mexico
Tobi Kosanke and Zehui(Tim) Huang
Provenance impacts not only the mechanical properties of sediments, but also the processes that can decrease, preserve or increase the porosity and permeability of a reservoir. We have modeled the effects of composition and burial (temperature and pressure) history on sediments representing a variety of locations in the Gulf of Mexico (GOM) basin to investigate the combined impacts of provenance and burial history on sediment reservoir quality. The reservoir quality of sediments of any particular age and location in the GOM strongly depends on their provenance and burial history. Sediment that is locally derived from uplifted volcanic terrains are mineralogically distinct from other, more regional sources, such as the Rocky Mountains, Ouachitas and Appalachians. Sands that are quartz-rich are typically characterized by porosity that is occluded by quartz cement where deeply buried. Volcanic-rich sands, however, typically have less quartz cement but low permeability and intergranular porosity due to the compaction of ductile rock fragments. The occurrence of early chlorite grain coats can inhibit the development of pervasive quartz cement in quartz-rich sediments while intergranular porosity in ductile-rich sands may be preserved through early overpressure that prevents compaction. Salt bodies, which have high thermal conductivity and very low permeability, impact both thermal transfer and fluid flow, thereby helping to preserve the porosity and/or permeability of clastic sediments in certain cases. By understanding and combining spatial and temporal mineralogic changes with accurate burial histories from multi-dimensional basin modeling, we are able to develop improved pre-drill predictions of reservoir quality in the Gulf of Mexico.
AAPG Search and Discovery Article #90167©2013 GCAGS and GCSSEPM 63rd Annual Convention, New Orleans, Louisiana, October 6-8, 2013