Print this pageA Model for the Discovery of a Hydrocarbon Bearing Listric Fault 
System
D. P. Stapp
Independent Consulting Geologist for Black
Oil Company, Inc. Addison, TX
The occurrence of hydrocarbon-trapping listric fault systems has
been known in the latter history of oil and gas exploration. The fault
mechanisms associated with these types of structural occurrences are
not simple expressions of linear/hinge type movements. The afterreaction
of a major structural component is not necessarily a rare
situation and has been well recognized in the exploitations of hydrocarbons.
Such an example of a listric fault system in a highly complex
basinal area has been identified in the Marietta-Ardmore Basin of
Southern Oklahoma and North Texas. We conclude that the simultaneous
action of the generation of the Sherman Anticline and a
listric fault system in Grayson County, Texas has generated a small
but very prolific structural/stratigraphic accumulation of hydrocarbons.
The asymmetrical Sherman anticline lies about four miles
southwest of the Oauchita thrust front, with its axis more or less
parallel to the thrust front, suggesting that the final or thrusting
movements may have influenced its structural development. The
movement of this feature probably induced the generation of a listric
fault with rollover folds which are very important structural traps in
the John Hudgins lease of Grayson County, Texas. Being located
toward the foreland portion of the basin, these folds are probably
within a passive margin of the basin. The gravitational action thus
formed longitudinal folds as a result of movement on the listric fault
system. Thus the accumulation of hydrocarbons in the clastic sequences
of lower Pennsylvanian age (Baker and Davis) formations
has occurred in these rollover folds, especially since the Baker is
sourced by the Atoka shales just below and the Davis is recognized
by most geologists familiar with this basin as petroliferous. The identification
of this listric fault system was isolated from a 3-D seismic
program coupled with a regional geologic and geophysical foreknowledge
of the character of the basin. Characterization of this fault
system in such a structural trap
has provided the basis for the revelation
of a new oil and gas field, and the resulting optimization of
well placement for optimum reservoir drainage.
AAPG Search and Discovery Article #90905©2001 AAPG Southwest Section Meeting, Dallas, Texas