Hydraulic Fracturing Induced Seismicity in Ohio in 2016: Case study of the Conotton sequence in Harrison County
Abstract
In November of 2016, a sequence of hydraulic fracturing induced seismicity was observed in Harrison County, Ohio. The events in this sequence were ≤ M 2.7 and were spatiotemporally correlated with hydraulic pumping stages from the Conotton horizontal wells. A series of adjacent wells to the west of the Conotton wells also induced seismicity along an east-west trending basement fault system. The fault's east-west trend extended beneath the Conotton horizontals based on seismicity observed in 2015, and the seismicity from the Conotton stimulation is an extension of the same fault system. Using a 5 station seismic network, 129 earthquakes were located using Hypoinverse. Relative locations were obtained using HypoDD and demonstrate that the activity was split into two depth populations: those that were shallow and directly below the Paleozoic Utica formation in which hydraulic fracturing was happening, and those that were deeper and related to the crystalline basement fault system. In addition, cross-correlation template matching techniques were used to observe some 1200 detections of earthquakes with M > -0.85. Interestingly, the b-value evolved from values > 1 early in the sequence to < 1 when the larger events started happening. During the sequence, the operator took mitigation actions by skipping stages and reduced volume across stages that were closer to the fault. Production data from the wells were also examined to investigate how interactions with a fault influence produced oil, gas, and brine.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.S32A..07F
- Keywords:
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- 4475 Scaling: spatial and temporal;
- NONLINEAR GEOPHYSICSDE: 7215 Earthquake source observations;
- SEISMOLOGYDE: 7223 Earthquake interaction;
- forecasting;
- and prediction;
- SEISMOLOGYDE: 8164 Stresses: crust and lithosphere;
- TECTONOPHYSICS