Impact of Fluvial Stratigraphic Response to Early Eocene Hyperthermal Events on Fluvial Reservoir Properties in the Tornillo Basin, West Texas

Abstract

Fluvial petroleum reservoirs exhibit large spatial variability in reservoir properties. This heterogeneity is due to variability in lithofacies distribution and stacking that conspire to produce a range of architectural styles. Fluvial architecture is ultimately controlled by the interactions of environmental conditions, sediment supply, and subsidence, and major changes in fluvial successions (e.g., fluvial style, stacking, and grain size) have been increasingly correlated to tectonic and climatic forcing mechanisms. However, our understanding of fluvial response to environmental perturbations is still largely conceptualized in 1D stratigraphic successions. Strata in the Tornillo Basin, W Texas, preserve a continuous record of alluvial-fluvial sedimentation through the early Eocene, in which coarser grained intervals have been correlated to early Eocene hyperthermal climate events by δ13C isotopes, and formation bounding surfaces have been linked to local Laramide faulting. A well-exposed, continuous, ~2-km-long outcrop belt of these strata offers an excellent opportunity to explore the 2-3D stratigraphic response to major climate and tectonic perturbations. I will utilize drone photogrammetric images to make 2-3D stratigraphic architectural interpretations, accompanied by grain size analysis, paleocurrent measurements, and lithofacies analysis calibrated by 1D measured sections to characterize the spatial and temporal response to early Eocene climate events. Detrital zircon analysis will provide maximum depositional age control on the stratigraphy. Detailed study of a well-exposed fluvial outcrop belt with recognized climatic and tectonic events will improve understanding of tectonic and climatic controls on 2-3D fluvial reservoir architecture and heterogeneity.

AAPG Datapages/Search and Discovery Article #90351 © 2019 AAPG Foundation 2019 Grants-in-Aid Projects