South-Central Section - 52nd Annual Meeting - 2018

Paper No. 15-2
Presentation Time: 8:30 AM-6:00 PM

DELAWARE BASIN EVAPORITE KARST GEOHAZARD CHARACTERIZATION, TEXAS: COUPLING OF TRADITIONAL KARST ANALYSES WITH REMOTE SENSING CHARACTERIZATION


STAFFORD, Kevin W.1, BROWN, Wesley2 and FAULKNER, Melinda1, (1)Geology, Stephen F. Austin State University, P.O. Box 13011, SFA Station, Nacogdoches, TX 75962, (2)Department of Geology, Stephen F. Austin State University, Nacogdoches, TX 75962

Evaporite karst development in the Permian Castile Formation within the Delaware Basin of West Texas and southeastern New Mexico poses significant geohazard risk for infrastructure throughout the region. Karst geohazards range from shallow, laterally-limited epigene karst manifestations to complex, vertically-extensive hypogene features, attesting to a complex speleogenetic history for the region. Additionally, suffosion processes in indurated gypsic soils are often coupled with karst phenomena to produce unstable, near-surface geohazards that are highly susceptible to anthropogenic modifications.

Traditional karst surveys, including land surveys and mapping of porosity structures, were coupled with remote sensing methods to delineate the distribution and variability of karst phenomena associated with RM 652 in northern Culberson County, Texas. LiDAR analyses, both elevation and intensity modeling, were used to delineate surface irregularities including open and filled sinkholes as well as small-scale solution and suffosion conduits connected to the land surface. Direct Current (DC) and Capacitively Coupled (CC) resistivity were utilized to assess shallow karst phenomena that do not readily manifest at the land surface. Orthophoto analyses of lineaments and vegetation were conducted to correlate traditional karst studies, LiDAR-based analyses and geophysical data in order to refine spatial distribution and characterize total evaporite karst phenomena. The results of this work provide detailed information for risk assessment for improved engineering to reduce or eliminate potential geohazard risks. Similar studies could provide valuable risk data for geohazard avoidance associated with other activities associated with increased hydrocarbon exploration and extraction, such as new road construction, pipeline installation and well-pad placement.