%A Jeremy Boak
%T Patterns of induced seismicity in central and northwest Oklahoma
%X Oklahoma experienced an average of 1.6 earthquakes of Magnitude 3 or greater (M3.0+) from the 1980s through 2008. Since that time, seismicity has increased to 907 M3.0+ earthquakes in 2015. More than 95% of these earthquakes occur over only ~17% of the area of Oklahoma (Figure 1). This pattern is generally attributed to increased injection of saline formation water co-produced along with oil and gas into the underpressured and relatively permeable Arbuckle Group, which lies directly on top of Precambrian crystalline basement (for example, Walsh and Zoback, 2015). Pressure communication from the Arbuckle to faults in the basement is interpreted to have reduced effective normal stress on the faults. This stress reduction allows faults aligned favorable with respect to the stress field in Oklahoma (SHMax = N 85° E) to move. This paper discusses the evolution of this seismicity, the regulatory actions taken to reduce seismicity by reducing deep injection, and the importance of declining oil price in reducing injected volumes in advance of full implementation of these regulatory directives
%D 2016
%K pore pressure, induced seismicity, hydrology, Basement, earthquake
%L epos2027