TEXAS BASEMENT SYNTHESIS PROJECT: CHARACTERIZING GEOLOGICAL RISK FACTORS OF BASEMENT-INVOLVED SEISMICITY

The hydraulic and mechanical properties of crystalline basement and adjacent reservoir rocks influence the communication of fluids, fluid pressure, and stress from production and saltwater disposal intervals to basement-involved faults. Lithologic, structural, and metamorphic fabric, fracture intensity, weathering and alteration history, and the nature of the overlying strata may all impact the hydromechanical properties of the upper basement and the basement-sediment interface. Variations in these properties may in turn influence the seismogenic response of basement-involved faults to production and disposal in the overlying sedimentary sequence. In order to reduce risk and better understand the rock properties impacting basement-involve seismicity, The Center for Integrated Seismicity Research at the Bureau of Economic Geology has begun the Texas Basement Synthesis Project. We seek a synoptic view of basement properties across the state of Texas, drawing from academic and industrial data sets, to constrain depth to basement, lithotectonic framework of basement rocks, and the nature and hydromechanical attributes of the upper basement and basement-sediment interface. The ultimate goal is to develop predictive models of hydromechanical properties based on lithologic and tectonostratigraphic correlations, inherited structure, and exhumation and burial history from superjacent strata. We will present preliminary, state-wide maps of basement rocks, adjacent sedimentary cover, and data gaps, and welcome expert input and insight into Texas basement properties from all sectors. We are particularly interested in legacy data that may help constrain basement characteristics in both low-data density regions and in seismically active basins with ongoing industrial operations.