POTENTIAL IMPACTS TO LANDSCAPES AND HYDROLOGIC FLOWS FROM ABOVE-GROUND ACTIVITIES IN THE EAGLE FORD SHALE PLAY

Producing hydrocarbons from tight formation source rocks has become one of the most important changes in the North American petroleum industry in decades. The Eagle Ford (EF) Shale Play in southern Texas is currently one of the most important with respect to oil and gas production. In a 12 year period, the number of wells drilled into the EF has nearly doubled the number of wells drilled over a 90 year period in the Austin Chalk, the overlying formation in the same geographic area. This rapid increase in activity in South Texas is also accompanied by a rapid increase in construction of drilling pads, roads, pipelines, and other necessary infrastructure. Though substantial research is devoted to potential below-ground impacts from drilling and hydraulic fracturing, less research has focused on landscape impacts, like fragmentation, soil erosion, etc. In this study, we assess the spatial and geomorphic fragmentation effects of the recent shale boom in south Texas, where reduced rainfall rates could substantially lengthen landscape reclamation periods. The play sits within several ecological regions, including the Southern Texas Plains, the Central Texas Plains, and the Blackland Prairies. In this work, we have created a database (ArcGIS) that includes all wells drilled, pipelines, and many roadways across the play, and have placed these features onto base maps of land cover (NLCD), soil type, vegetation assemblages, and hydrologic units. We then use different landscape fragmentation algorithms (e.g., third-party ArcGIS Landscape Fragmentation Tool, v 2.0) to assess changes to the continuity of these different ecoregions and the landscapes that support them. Though results are preliminary, we show a slow but steady increase in the number of wells per pad, an increase in the fragmentation of ecosystems, an increase in the potential for soil loss, and possible alterations to hydrologic systems. Results indicate that small changes in infrastructure placement may reduce ecological impacts.