loading page

Revisiting the Timpson Induced Earthquake Sequence: A System of Two Parallel Faults
  • Kaiwen Wang,
  • William L. Ellsworth,
  • Gregory C. Beroza
Kaiwen Wang
Stanfrod University

Corresponding Author:[email protected]

Author Profile
William L. Ellsworth
Stanford University
Author Profile
Gregory C. Beroza
Stanford University
Author Profile

Abstract

The 17 May 2012 M4.8 Timpson earthquake is the largest known earthquake in eastern Texas. It is suspected to have been induced by wastewater injection from two nearby, high-volume wells. Its cataloged aftershocks form a NW-SE trend, which unlike other induced earthquakes sequences, is unfavorably oriented for failure in the local stress field. To understand this, we enriched the catalog using PhaseNet, a deep-learning-based picker followed by double-difference relocation with cross-correlation-based differential traveltimes. We clustered the aftershocks based on waveform similarity. Most of the seismicity falls into two-clusters, which define a complex fault structure of two parallel subfaults that are more favorably oriented than the overall trend. We inferred from waveform similarity that the sequence initiated on the northern subfault with a M3.9 foreshock and M4.8 mainshock, then extended to the southern subfault with a M4.1 aftershock, and was finally reactivated on the northern subfault with two more M4 events.
16 Aug 2020Published in Geophysical Research Letters volume 47 issue 15. 10.1029/2020GL089192