Induced earthquakes. Sharp increase in central Oklahoma seismicity since 2008 induced by massive wastewater injection

Science (Impact Factor: 33.61). 07/2014; 345(6195). DOI: 10.1126/science.1255802
Source: PubMed


Unconventional oil and gas production provides a rapidly growing energy source; however, high-production states in the United
States, such as Oklahoma, face sharply rising numbers of earthquakes. Subsurface pressure data required to unequivocally link
earthquakes to wastewater injection are rarely accessible. Here we use seismicity and hydrogeological models to show that
fluid migration from high-rate disposal wells in Oklahoma is potentially responsible for the largest swarm. Earthquake hypocenters
occur within disposal formations and upper basement, between 2- and 5-kilometer depth. The modeled fluid pressure perturbation
propagates throughout the same depth range and tracks earthquakes to distances of 35 kilometers, with a triggering threshold
of ~0.07 megapascals. Although thousands of disposal wells operate aseismically, four of the highest-rate wells are capable
of inducing 20% of 2008 to 2013 central U.S. seismicity.

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Available from: Matthew Weingarten, Jul 27, 2014
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    • "). In the U.S., seismic events have been associated with the development of oil and gas operations on numerous occasions (Davies et al., 2013; Ellsworth, 2013; van der Elst et al., 2013; Keranen et al., 2014 "
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    • "To date, induced seismicity has been related to various anthropogenic applications such as dam impoundment, wastewater disposal, fluid extraction, overburden removal, enhanced geothermal systems, and hydraulic fracturing [e.g., Davies et al., 2013]. Recently, focus has shifted toward understanding induced seismicity in light of the growing concern over its potential for hazard [Ellsworth, 2013; Keranen et al., 2014; Atkinson et al., 2015]. "
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    • "Recent seismicity events likely related to disposal of waste fluid from hydraulic fracturing [1] have revived the concern that large-scale CO 2 injection will trigger earthquakes and that even small-to moderate-sized earthquakes may threaten the seal integrity of the injection zone (e.g., [2] [3] [4]). [3] stated that " Because of the critically stressed nature of the crust, fluid injection in deep wells can trigger earthquakes when the injection increases pore pressure in the vicinity of preexisting potentially active faults. "
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