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Nevada Earthquake Swarm Increases Chance of Larger Quake
An anonymous reader writes Hundreds of small earthquakes have been gaining in strength in northwestern Nevada. The Nevada region bordering California and Oregon was hit by 18 quakes in less than 24 hours, with magnitudes measuring from 2.7 to 4.5. According to CNN: "This does not necessarily mean a big one will come, state seismologists said, but they added that it's good to be prepared, just in case. Seismologists refer to such quake groupings as swarms, and the U.S. Geological Survey has detected them regularly. They can produce thousands of small tremors."
L'Aquila, Italy, 2009.
Mistakes must not be repeated.
One would think that the quakes would be on the faults where the fracking sites in Nevada are rather than a completely unrelated set of faults 400 miles away where they aren't.
Nevada is a tectonically active area undergoing substantial amounts of stretching (purple dots = historical quakes). It's the whole reason for the "basin-and-range" topography that typifies the region. But, no, it sounds like hydraulic fracturing?
Highly unlikely. According to this map of oil and gas potential in Nevada [PDF], there aren't any oil and gas wells in that part of the state (western edge of Sheldon National Antelope Refuge), and even the oil and gas potential in that area is essentially nil due to the geology, such as the presence of an old volcanic caldera there (the northwesternmost red blob is practically on top of the area of the earthquake swarm). The conodont samples referred to on that map are a way to assess how much the local rocks have been heated. To the east of the earthquake area the square dots are red, indicating the rocks are thoroughly roasted. Other geology maps indicate the area is mostly volcanic and intrusive igneous rocks. There's no oil and gas drilling there. Zip.
Nevada being a rather tectonically active area, suspecting it is from hydraulic fracturing is pretty unlikely in the first place. I know hydraulic fracturing is the favorite punching bag of people these days for anything related to any geological hazard, but there are plenty of natural causes before leaping to that conclusion.