Basin Modeling of
the
Maze, Will1,
M. J. Hardy2, George Grabowski1, Christopher L. Roll1,
Leonard V. Moore1 (1) ExxonMobil
Exploration Company,
A long-term study of the regional geology of the Arabian Plate
provides an integrated framework in which to study the evolution of its
hydrocarbon systems. Our Stellar™ basin models incorporate source-rock
distribution and geochemistry tied to this regional stratigraphic
and structural framework.
The basic regional stratigraphy is
well established. However, one of the uncertainties for basin modeling is the
amount of stratigraphic section missing at
unconformities. We utilized well control and seismic coverage to constrain the
amount of section removed and to differentiate between erosion and non-deposition
in seven intervals.
Our models clearly show the regional geologic controls on
hydrocarbon generation near large features such as the Qatar Arch. Onset of
maturation of Silurian source rocks started in the Late Triassic, hundreds of
kilometers NNW of North Dome, and progressed (episodically?) in a clockwise
direction around the dome from NNW to W. Generation likely continued into the
Tertiary in the SSW and along the crest of the arch.
Model results for Jurassic source rocks are similar, with maturation
beginning by Mid-Cretaceous, and generation continuing into the Miocene.
Cretaceous and Tertiary hydrocarbon systems are more areally
limited, due to Cretaceous obduction tectonics and
Tertiary Zagros foredeep
development.
The NE regional
tilt of the Arabian Plate increased during the Miocene,
moved the crest of the Qatar Arch south, and modified closures and migration
paths. Hydrocarbon generation turned off in areas of uplift and erosion, while
generation from younger source rocks occurred in the foredeep
and molasse basins of the Zagros.