SUBSURFACE GROUNDWATER STUDIES IN THE SAN SOLOMON SPRINGS REGION, REEVES COUNTY, TEXAS

The research area, located in Jeff Davis and Reeves Counties of West Texas, has recently been under extreme observation due to the discovery of the “Alpine High” or Wolfcamp Shale oil play. There is considerable concern about possible impact to local and regional springs from oilfield related activities. In this region many springs exist originating from aquifers including local Tertiary Igneous systems, Cretaceous Edwards-Trinity, Triassic Dockum, and aquifers of the Permian period; the Rustler of Ochoan Age, and the Capitan Reef Complex of Guadalupian age. The potentially largest most prolific aquifer in the research area is the Edwards-Trinity, which is of significant interest to this study as it may provide the largest contribution of source waters for the San Solomon Springs, one of the largest freshwater springs in Texas. Regional springs originate from a series of subsurface Laremide (NW-SE orientation) aged structures including folds and thrust faults along with a series of Basin and Range (N-S and E-W to NW-SE oriented) normal faults. These structures are very important in groundwater systems because of their impact on regional stratigraphy. Regional 3-D stratigraphic and structural models have been developed using well logs obtained at the Midland Energy Library. Analysis and study of these 3-D models allow for an understanding of regional groundwater flow patterns. Currently, sampling locations for obtaining geochemistry and stable isotope data (δO¹⁸ and D) are being chosen. Using the geochemistry and isotope information from each sampling location, correlation between the springs and inferred groundwater flow paths may be determined.