thumbnail

Shaking from injection-induced earthquakes in the central and eastern United States

Bulletin of the Seismological Society of America

By:
ORCID iD
https://doi.org/10.1785/0120140099

Links

Abstract

In this study I consider the ground motions generated by 11 moderate (Mw4.0-5.6) earthquakes in the central and eastern United States that are thought or suspected to be induced by fluid injection. Using spatially rich intensity data from the USGS “Did You Feel It?” system, I show that the distance decay of intensities for all events is consistent with that observed for tectonic earthquakes in the region, but for all of the events, intensities are lower than values predicted from an intensity prediction equation that successfully characterizes intensities for regional tectonic events. I introduce an effective intensity magnitude, MIE, defined as the magnitude that on average would generate a given intensity distribution. For all 11 events, MIE is lower than the event magnitude by 0.4-1.3 magnitude units, with an average difference of 0.82 units. This suggests that stress drops of injection-induced earthquakes are systematically lower than tectonic earthquakes by an estimated factor of 2-10. However, relatively limited data suggest that intensities for epicentral distances less than 10 km are more commensurate with expectations for the event magnitude, which can be reasonably explained by the shallow focal depth of the events. The results suggest that damage from injection-induced earthquakes will be especially concentrated in the immediate epicentral region.

Additional publication details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Shaking from injection-induced earthquakes in the central and eastern United States
Series title:
Bulletin of the Seismological Society of America
DOI:
10.1785/0120140099
Volume:
104
Issue:
5
Year Published:
2014
Language:
English
Publisher:
Seismological Society of America
Contributing office(s):
Earthquake Science Center
Description:
8 p.
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
Bulletin of the Seismological Society of America
First page:
2619
Last page:
2626
Country:
United States