Part 4 - Berg - Hughes Center
Part 4 - Berg - Hughes Center
Part 4 - Berg - Hughes Center
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generation (Table 4). The following characterization of the Bossier shale beds is based on<br />
the geological studies (Tables 5-8 and Figs. 333-341) by Don Goddard and Marty Horn at<br />
LSU and geochemical analyses (Table 9 and Figs. 342-348) by Suhas Talukdar with<br />
Baseline Resolution, Inc. The Bossier shale beds are thermally mature and represent<br />
petroleum source rocks that generated and potentially expelled mostly gas and some oil.<br />
These shale beds at their present maturity level have mostly low to moderate total organic<br />
carbon contents and Type III kerogen. Original kerogen types in the immature stage, as<br />
assessed by kerogen petrography, were mainly gas-prone Type III and some oil and gas<br />
prone Type II/III. The principal macerals are partly oxidized, unstructured amorphous<br />
organic matter (liptinite) and vitrinite in varying proportions. Amorphous material was<br />
derived from degraded marine algal and humic matter (higher plant material). Visual<br />
kerogen data support the predominantly gas prone nature of the source rocks. Vitrinite<br />
reflectance (Ro) values (0.94 % to 2.62%) and thermal alteration indices (TAI) (2 + to 3 + )<br />
suggest that these source rocks entered the late oil window to main gas maturity window<br />
and thus have generated mostly gas with some oil. Thin section petrography of<br />
geochemically analyzed intervals documents the following rock types: muddy fine-<br />
grained sandstone, laminated fine-grained sandstone, sandy mudstone, and silty<br />
mudstone. These combined analytical results indicate that abundant woody organic<br />
material of continental origin was deposited in offshore areas in association with fine<br />
siliciclastic sediments in a marine prodelta environment during the Late Jurassic to Early<br />
Cretaceous. The thickness and widespread deposition of predominantly gas-prone source<br />
rocks within this basin and their high thermal maturity led to potential sourcing of mainly<br />
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