Sandy depositional environments in the Bossier Shale (a mud-dominated system) of the East Texas basin range from fluvial to deep water. Their occurrence is controlled by a combination of climate and sea level change.
Sequence/seismic stratigraphic analysis of well logs and 2-D seismic lines from the East Texas basin demonstrates that the Bossier Shale can be subdivided into two sequences separated by a major sequence boundary (SB-2). Bossier Shale is also bracketed by a basal (SB-1) and upper (SB-3) sequence boundary separating it from the Cotton Valley Lime below, and the Cotton Valley Sand above.
In seismic sections, the mid-Bossier (SB-2) boundary was identified by tracing mounded reflectors, and sigmoid signatures representing basin floor and slope fans. SB-2 correlated onto the shelf below stacked deltas. In well log sections, basin floor fans were traced laterally into slope fans and stacked deltas. These basin floor and slope fans represent a lowstand systems tract, whereas the Lower Bossier represents a transgressive systems tract and the upper Bossier is a prograding complex.
Burial history analysis suggests the Lower Bossier accumulated during rapid mechanical subsidence when the East Texas basin was underfilled. Sea level drop associated with the SB-2 represents a major climate shift from tropical to cooler conditions favoring rapid influx of sands from the ancestral Mississippi, Ouachita and Red River Systems. These sands developed inner shelf prograding deltas, outer shelf and incised valley fill stacked deltas, and basin submarine fan systems. Their occurrence is due to a combination of global cooling and sea level change.
Recent exploration activity in Robertson County, TX, appears to focus on base-of-slope to basin floor fan plays. Alternate explanations are possible and may include distal pro-deltas at the shelf-edge of incised valleys. The distribution of associated deep-water equivalent seismic features over a wide area suggest long-term potential for the Bossier Play
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Dr. George Klein earned degrees in geology from Wesleyan University (BA), Kansas (MS) and Yale (PhD.). He worked as a Research Geologist for Sinclair Research and then taught at the Universities of Pittsburgh, and of Pennsylvania. He joined the University of Illinois in Urbana-Champaign in 1970 where he served as a Full Professor from 1972 until 1993. Klein received eleven honors and awards including the Outstanding Paper Award in the Journal of Sedimentary Petrology (SEPM; 1972) a Senior Research Fellowship from the Japan Society for the Promotion of Sciences, a Senior Fulbright Research Fellowship in the Netherlands, and the Laurence L. Sloss Award of the Geological Society of America. After serving as Executive Director of the New Jersey Marine Sciences Consortium, and Director, New Jersey Sea Grant College Program, he opened a full time geological consulting practice (SED-STRAT Geoscience Consultants, Inc.) in the petroleum field in May 1996. He is a licensed Texas Registered Geologist (#440), and a member of AAPG (DPA Board CPG #5662), HGS, SEG, SIPES (CPES #2705), SEPM, and GSA.
Dr.Klein has expertise in Play Concepts, Clastic Facies and Reservoirs (Deepwater, Deltas, Fluvial), Clastic Sequence and Seismic Stratigraphy, Seismic Sedimentology, Basin Analysis, Clastic Reservoir Characterization, and Framework Geology. Klein provides consulting services in these fields. Basins with which he has expertise include the Gulf Coast, Gulf of Mexico, East Texas, Maverick, Permian, Midland, Illinois, San Joaquin, Appalachian, Arkoma, Powder River, Maracaibo, Macuspana, Eastern Venezuela, Marib, Orange River, Senegal, Lower Congo, Eastern Carpathian, Veracruz, Cook Inlet, and Fundy basins. He published 300 refereed articles, books and abstracts on these topics, including the book "Sandstone Depositional Models for Exploration for Fossil Fuels" and a widely-used Wall Chart on "Vertical Sequences and Log Shapes of Major Sandstone Reservoir Systems".
Klein discovered160 mmbo oil and 3.2 tcf gas (both solo and as team member) including the largest gas producing well in the Barber County field, WV, a new exploration play concept in the eastern Gulf Coast, a delta-front trough play concept in the Reconcavo basin, Brazil, a deep water channel fairway system and sheet sand play in the Veracruz basin, Mexico, a slope fan/basin floor fan play in the East Texas basin, a strandplain play in the Macuspana basin, Mexico, a turbidite channel/fan play in the Senegal basin, West Africa, a prograding fluvio-deltaic play complex in offshore Angola, and a reef play in Canada.