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Oklahoma's recent earthquakes and saltwater disposal.

ABSTRACT: Over the past 5 years, parts of Oklahoma have experienced marked increases in the number of small- to moderate-sized earthquakes. In three study areas that encompass the vast majority of the recent seismicity, we show that the increases in seismicity follow 5- to 10-fold increases in the rates of saltwater disposal. Adjacent areas where there has been relatively little saltwater disposal have had comparatively few recent earthquakes. In the areas of seismic activity, the saltwater disposal principally comes from "produced" water, saline pore water that is coproduced with oil and then injected into deeper sedimentary formations. These formations appear to be in hydraulic communication with potentially active faults in crystalline basement, where nearly all the earthquakes are occurring. Although most of the recent earthquakes have posed little danger to the public, the possibility of triggering damaging earthquakes on potentially active basement faults cannot be discounted.

SUBMITTER: Walsh FR

PROVIDER: S-EPMC4640601 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Oklahoma's recent earthquakes and saltwater disposal.

Walsh F Rall FR Zoback Mark D MD

Science advances 20150618 5

Over the past 5 years, parts of Oklahoma have experienced marked increases in the number of small- to moderate-sized earthquakes. In three study areas that encompass the vast majority of the recent seismicity, we show that the increases in seismicity follow 5- to 10-fold increases in the rates of saltwater disposal. Adjacent areas where there has been relatively little saltwater disposal have had comparatively few recent earthquakes. In the areas of seismic activity, the saltwater disposal princ ...[more]

PMID: 26601200

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Oklahoma's recent earthquakes and saltwater disposal.

Publications

Oklahoma's recent earthquakes and saltwater disposal.

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