EARTHQUAKE HAZARD
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61 Quakes rattled Oklahoma since Feb. 18, as two tremors shut fracking in Ohio well
It must be quite surreal living near Oklahoma city these days, with an average of about three shallow tremors rattling the nearby areas each day.
Three of the tremors measured magnitude 3.8 (Mw) and two others registered at 3.7Mw. Nearly all the tremors have occurred at a depth of about 5km.
Earthquake Location Map. Oklahoma Earthquakes since February 18, 2014. Source: USGS/EHP
Tectonic Summary
Earthquakes in the Stable Continental Region – Natural Occurring Earthquake Activity
[Excerpts from USGS/EHP]
Most of North America east of the Rocky Mountains has infrequent earthquakes. Here and there earthquakes are more numerous, for example in the New Madrid seismic zone centered on southeastern Missouri, in the Charlevoix-Kamouraska seismic zone of eastern Quebec, in New England, in the New York – Philadelphia – Wilmington urban corridor, and elsewhere. However, most of the enormous region from the Rockies to the Atlantic can go years without an earthquake large enough to be felt, and several U.S. states have never reported a damaging earthquake.
Induced Seismicity
As is the case elsewhere in the world, there is evidence that some central and eastern North America earthquakes have been triggered or caused by human activities that have altered the stress conditions in earth’s crust sufficiently to induce faulting. Activities that have induced felt earthquakes in some geologic environments have included impoundment of water behind dams, injection of fluid into the earth’s crust, extraction of fluid or gas, and removal of rock in mining or quarrying operations. In much of eastern and central North America, the number of earthquakes suspected of having been induced is much smaller than the number of natural earthquakes, but in some regions, such as the south-central states of the U.S., a significant majority of recent earthquakes are thought by many seismologists to have been human-induced. Even within areas with many human-induced earthquakes, however, the activity that seems to induce seismicity at one location may be taking place at many other locations without inducing felt earthquakes. In addition, regions with frequent induced earthquakes may also be subject to damaging earthquakes that would have occurred independently of human activity. Making a strong scientific case for a causative link between a particular human activity and a particular sequence of earthquakes typically involves special studies devoted specifically to the question. Such investigations usually address the process by which the suspected triggering activity might have significantly altered stresses in the bedrock at the earthquake source, and they commonly address the ways in which the characteristics of the suspected human-triggered earthquakes differ from the characteristics of natural earthquakes in the region.
Ohio Quakes
Ohio authorities have stopped a fracking operations at Carbon Limestone Landfill in Lowellville, after two temblors hit Mahoning County.
The quakes occurred in Poland Township and the village of Lowellville near the Pennsylvania border on Monday in. The first tremor was a magnitude 3.0 shock, followed by a second measuring 2.6Mw, said USGS/EHP. Local media reported two smaller aftershocks later.
The quakes prompted Ohio Department of Natural Resources (ODNR) to order suspension of drilling operation at Carbon Limestone Landfill in Lowellville. The area is plagued by up to 20 wells, used by Hilcorp Energy for horizontal drilling.
“Out of an abundance of caution we notified the only oil and gas operator in the area, and ordered them to halt all operations until further assessment can take place,” said the ODNR public information officer.
“ODNR is using all available resources to determine the exact circumstances surrounding this event and will take the appropriate actions necessary to protect public health and safety.” He said.
“It’s an area which [before 2011] had no history of earthquakes,” said John Armbruster, a retired Columbia University geology professor who had worked with Ohio officials to monitor a recent series of earthquakes tied to a fracking-waste injection well near Youngstown.
“It looks very, very suspicious.”
“We never had a recorded earthquake in Mahoning County [before 2011] … then four [strike] in one day,” said Raymond Beiersdorfer, a geologist at Youngstown State University. “It’s definitely a testable hypothesis.”
The U.S. production of crude oil using fracking increased by more than 15 percent in 2013.
Earthquake Related Links
- Another Swarm of Shallow Quakes Strikes Close to Oklahoma City February 18, 2014
- More Quakes Strike Oklahoma February 11, 2014
- Significant Earthquakes Strike Oklahoma December 29, 2013
- M4.5 Quake Strikes NE Edmond Oil and Gas Field, Oklahoma December 8, 2013
- 41 Earthquakes Strike Oklahoma in November December 1, 2013
- Earthquake No. 19 Strikes N. Texas November 29, 2013
- Two More Quakes Strike North Texas November 29, 2013
- Oil Drilling Likely Caused Texas Earthquake Posted on May 17, 2009
- M3.3 Quake Strikes Azle, Texas Posted on November 25, 2013
- FEWW Earthquake Links
Drilling Related Earthquakes
Fracking Related Links
Fire Earth 