***Please note venue***
$35.00 Late Registration
Department of Geological Sciences and Bureau of Economic Geology
Jackson School of Geosciences
The University of Texas at Austin
Abstract: Insights into Permian Basin reservoirs from Holocene-Pleistocene sediments and strata of the Bahamian-Caicos Archipelago
Understanding the architecture of carbonate reservoir strata is a fundamental step in improved recovery as well as accurate volumetric analysis of both conventional and unconventional reservoirs. Complex interactions between physically dominated and biologically dominated sedimentologic processes, overprinted by prolonged diagenetic modifications creates significant challenges for geoscientists and engineers working to predict reservoir quality and connectivity and their impact on fluid flow and recovery efficiency. One path to better understanding these systems has been to study modern depositional systems. Field study of modern carbonates provides invaluable insights into the origin of carbonate strata and scales of heterogeneity in natural systems. This said, there remains a vast leap of faith in projecting modern depositional patterns into ancient stratigraphic sequences, so how do we best bridge this conceptual gap?
Data for this presentation include high-resolution remote sensing images covering the entire Bahamian-Caicos archipelago covering subaerial deposits and extending to 200 m water depth locally. Shallow coring at both exploration and development scales, detailed radiometric dating, and surface geologic mapping with sub-meter resolution, it is now possible to add the 4th dimension to our otherwise three-dimensional field experiences in modern carbonate platforms. The ability to conduct stratigraphic analysis of ancient strata with a well-constrained (as opposed to highly conjectural) sea-level curve, to know depositional age with a precision of 1,000 yr or less, and to thus tie deposits and diagenetic overprints to this eustatic-chronostratigraphic model, yields new and sometimes surprising results.
This talk will review both Bahamas-Caicos-wide perspectives and then focus in to reservoir-scale variability from the islands of West Caicos and San Salvador. A new appreciation of cross-platform facies variability driven by wind-driven wave energy highlights new exploration-fairway concepts. Stratigraphic analysis shows that some of the most obvious unconformities across the islands tied to remarkably short-lived eustatic events that are sub-Milankovitch in duration (ie <20 ka). Intercalation of weakly cemented Mg-calcite dominated and extensively leached and cemented aragonitic sediments at the scale of 20-200 ka time scale defies current generalizations about icehouse vs greenhouse patterns. For someone who has been studying carbonates across the world in outcrop since 1974 and in the subsurface since 1982, the perspectives from the Plio-Pleistocene record of the Bahamas has opened my eyes as few experiences have.
Charlie Kerans is Goldhammer Chair of Carbonate Geology at the Department of Geological Sciences, and co-Principal Investigator of the Bureau of Economic Geology's Carbonate Reservoir Characterization Research Laboratory, Jackson School of Geosciences, The University of Texas at Austin. Since 2006 Kerans has held an appointment at the Department of Geosciences as Goldhammer Chair of Carbonate Geology and offers courses in modern and ancient carbonate deposition and diagenesis as well as sequence stratigraphy. Areas of focus are carbonate sequence stratigraphy and reservoir characterization, with an emphasis on integrating outcrop analog information for improved understanding of the subsurface. Kerans has won 10 best paper/poster/oral presentation awards with co-workers and students, including two Wallace Pratt awards for best published paper in AAPG, and the Carlos Dengo award for best paper presented at the International AAPG in South Africa in 2008. In 2014 Kerans was named AAPG Grover Murray Distinguished Educator. He also was received the Society of Sedimentary Geology's second highest medal, the Francis J. Pettijohn Medal, for Distinguished Contributions to Sedimentology in 2014, and for 2017 the SEPM Honorary Membership Award At the Jackson School Kerans has won three Knebel teaching awards as well as the Walter Award.