Seismicity During the Initial Stages of the Guy‐Greenbrier, Arkansas, Earthquake Sequence
We analyze the background seismicity, initiation, and earliest stages of the Guy‐Greenbrier, Arkansas, earthquake sequence, which was potentially induced by wastewater injection starting in July 2010, during the 3 month time period 1 June to 1 September 2010. High‐resolution observations of low‐magn...
| Published in: | Journal of Geophysical Research: Solid Earth |
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| Main Authors: | , , , |
| Format: | Article in Journal/Newspaper |
| Language: | unknown |
| Published: |
IASPEI, GFZ German Research Centre for Geosciences
2017
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| Subjects: | |
| Online Access: | https://hdl.handle.net/2027.42/142265 https://doi.org/10.1002/2017JB014946 |
| Summary: | We analyze the background seismicity, initiation, and earliest stages of the Guy‐Greenbrier, Arkansas, earthquake sequence, which was potentially induced by wastewater injection starting in July 2010, during the 3 month time period 1 June to 1 September 2010. High‐resolution observations of low‐magnitude seismicity, and the high‐quality Arkansas public well database, facilitate detailed analysis of spatial and temporal correlations between earthquakes, wastewater injection, and hydraulic fracturing. We detected 14,604 earthquakes, with magnitudes −1.5≤ML≤2.9, using two sensitive, waveform similarity‐based event detection methods in parallel: Fingerprint And Similarity Thresholding, and template matching. We located the 1,740 largest earthquakes that form 16 spatially compact clusters, using P and S phases from 3 stations with the double‐difference relocation algorithm and an improved velocity model constrained by the location of quarry blasts. We enhanced the temporal resolution of these event clusters by assigning smaller unlocated events to a cluster based on waveform similarity. Most clustered earthquakes during this time were both spatially and temporally correlated with hydraulic fracturing stimulation at several production wells. For one cluster, microseismicity was correlated with individual stages of stimulation. Many other wells had no detectable nearby seismicity during stimulation. We found a smaller number of events located on the Guy‐Greenbrier Fault that were likely induced by wastewater injection. The concurrent presence of seismicity induced by hydraulic fracturing and wastewater injection presents a challenge for attribution and seismic hazard characterization, but the combination of precision seismology and high‐quality well information allows us to disentangle the effects of these two processes.Plain Language SummaryA magnitude 4.7 earthquake occurred in Arkansas in 2011, after several months of smaller earthquakes that started in July 2010. Many scientists think that pumping wastewater (from ... |
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