Part 4 - Berg - Hughes Center

Louisiana Salt Basin. Lower Cretaceous lime mudstone was an effective local petroleum
source rock in the South Florida Basin, and these rocks are possible source beds in the
North Louisiana Salt Basin given the proper organic facies. Upper Jurassic strata were
effective source rocks in Mexico and the East Texas Salt Basin; therefore, these strata are
possible source beds in this basin given the proper organic facies. Upper Cretaceous
marine shale probably is not a source bed in this basin given the thickness and organic
facies of this unit. Lower Tertiary shale and lignite have been reported to have been
source beds in south Louisiana and southwestern Mississippi, but these beds have not
been subjected to favorable burial and thermal maturation histories required for
petroleum generation in the North Louisiana Salt Basin.
Comparative Basin Evaluation
The origin and evolution of the North Louisiana Salt Basin and Mississippi Interior
Salt Basin are comparable, and Upper Jurassic Smackover lime mudstone beds are the
main petroleum source rock in both of these basins (Table 1). There is a significant
difference in the geohistories of these basins. This difference is the elevated heat flow the
strata in the North Louisiana Salt Basin experienced in the Cretaceous. This event is
primarily due to reactivation of upward movement, igneous activity, and erosion
associated with the Monroe and Sabine Uplifts.
The difference is the heat flow values between the North Louisiana Salt Basin (1.25
HFU) and the Mississippi Interior Salt Basin (1.09 HFU) results in the generation of
hydrocarbons being initiated at depths of 6,000 to 8,500 feet for the North Louisiana Salt
Basin and hydrocarbon generation commencing at depths of 8,000 to 11,000 feet for the
Mississippi Interior Salt Basin using a transient heat flow model (Table 1). This elevated
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