Seismicity Induced by Hydraulic Fracturing in Ohio
Observed Characteristics of Induced Seismicity: From Laboratory to Field Scale
Special Session: Observed Characteristics of Induced Seismicity: From Laboratory to Field Scale
Time: 5:00 PM
We have investigated seismicity associated with hydraulic fracturing (HF) in Ohio since 2013, which provides an ideal setting for studying the relations between high pressure injection and earthquakes due to isolation from other injection activities. Our analysis using an array of local stations in Harrison County revealed 2 distinct groups: 1) deeper earthquakes in Precambrian basement, with larger magnitudes (M>2), b-values < 1, and many post shut-in earthquakes, versus 2) shallower earthquakes in Paleozoic rocks ~400 m below HF, with smaller magnitudes (M<1), b-values > 1.5, and few post shut-in earthquakes. Based on geologic history, laboratory experiments, and fault modeling, we interpreted the deep seismicity as slip on mature faults in older crystalline rocks and the shallow seismicity as slip on immature faults in younger sedimentary rocks. Wells inducing deeper seismicity produced more water than wells with shallow seismicity, indicating more extensive hydrologic connections outside the target formation, consistent with pore pressure diffusion influencing seismicity. However, the 2-3 hours between onset of HF and seismicity is too short for typical fluid pressure diffusion rates across distances of ~1 km and argues for poroelastic stress transfer also having a primary influence on seismicity.
We now extend our analysis to other cases of HF induced seismicity in the Appalachian Basin. While these cases did not have publicly available local arrays, a broader set of stations operated by Miami University, ODNR, USGS, and IRIS is sufficient to identify the primary patterns of these seismic sequences. We employ multistation template matching to improve detection, waveform correlation to improve phase arrivals, and double difference relocation to improve the hypocentral characterization. We also examine frequency-magnitude distributions and well production patterns to compare with the geologic and operational interpretations made in the Harrison County study.
Brudzinski M. R. Miami University
Friberg P. A. Instrumental Software Technologies, Inc. (ISTI)
Kozłowska M. Miami University
Skoumal R. J. USGS
Langenkamp T. R. Miami University
Loughner E. A. Cedarville University
Currie B. S. Miami University
Fasola S. L. Miami University