Numerical Simulation Modeling of
Hydrocarbon Migration into and Through Sand Reservoirs in the Pabst Field (Main
Pass Block
259), Northern Gulf of Mexico
By
Yuxian Li1, Joel S. Watkins1, Roger Sassen1
(1) Texas A&M University, College Station, TX
Numerical simulation modeling of hydrocarbons charging reservoir sands provides a better understanding of the distribution of hydrocarbons in reservoir compartments and assists in the development of numerical simulation models used during the development and production. Herein, we report results of numerical simulation modeling of migration of hydrocarbon liquids into the 10,300-ft sand of the Pabst field in the northern Gulf of Mexico. The model is based on and constrained by geochemical, seismic and well-log data. Seismic amplitudes serve as proxies for gas-condensate distribution.
Sands in the Pabst field appear to have been deposited as delta-toe or
turbidites on an upper paleoslope. The field is complexly faulted. Three main
NW-SE trending growth faults and numerous low-throw NE-SW trending faults divide
the field into numerous compartments. The numerical simulation models indicate
that the three major growth faults mainly seal. Some communication between two
of the growth faults may have occurred across a local high-standing block
. The
NE-SW trending low-throw faults mainly form barriers. The main migration
pathways appear to be the two structurally lower growth faults. Geochemical data
shows that present condensate is highly mature and that it arrived late in the
field, flushing the earlier, heavier liquids as it migrated. The 10,300-sand
contains mainly condensates but other sands contain remnants of the earlier,
heavier hydrocarbons.