Abstract: Hydrocarbon migration
through faults and successive reservoir infilling in the Ghadames Basin,
Algeria
RUDKIEWICZ, JEAN-LUC, ROBERT DANIELS, and AHMED CHAOUCHE
Hydrocarbon migration
through faults is a long debated question. A case study in the Ghadames
Basin in southeastern Algeria has allowed one to point out the role of
faults and of capillary seals in the infilling of stacked reservoirs.
The hydrocarbon system in this
basin starts in Paleozoic units and comprises two source rocks and three
over- or interlying reservoir units. Migration
from the source to the reservoir
shows a succession of primary
migration
from the source to the local drains,
then local accumulations in traps and dismigration into the next overlying
trap. Dismigration from one reservoir to another occurs once the hydrocarbon
column exceeds the capillary barriers. The relative capillary entry pressures
of shaly seals, faulted seals or reservoirs induce a stepwise flow into
the plumbing system with successive pulses of
migration
.
The hydrocarbon system, which
may represent a good example for other Paleozoic basins, has been modeled
with the 2D compositional generation and migration
basin simulator Temiscomp.
This allowed understanding of the conditions of gas or oil occurrence in
the stacked reservoirs and prediction for further exploration targets.
AAPG Search and Discovery Article #90942©1997 AAPG International Conference and Exhibition, Vienna, Austria