California unseated as earthquake capital by unlikely newcomer

By Eric Zassenhaus

Published February 8, 2015 03:12 PM

Chad Devereaux examines bricks that fell from three sides of his in-laws home in Sparks, Okla., following two earthquakes that hit the area in less than 24 hours. A study published Thursday, July 3, 2014 by the journal Science explains how just four wells forcing massive amounts of drilling wastewater into the ground are probably causing quakes in Oklahoma. The wells seem to have triggered more than 100 small-to-medium earthquakes in the past five years, according to a study.

California is no longer the earthquake capital of the contiguous U.S., and even earthquake capital Alaska has been surpassed by an unlikely new contender, according to a new report.

That new capital is Oklahoma. Before 2009, the Sooner state was barely on the map, according to stats provided by the United States Geological Survey.

According to the Center for Investigative Reporting's study:

CIR's report found Kansas, Texas, Ohio and Colorado all had major upswings in seismic activity in recent years.

Citing studies, CIR says the increased amount of hydraulic fracturing — or fracking — of oil wells in those states is playing a significant role in causing the quakes.

It's not the drilling itself, these studies found, that causes the seismic activity. Instead, it appears to be the large underground wastewater ditches that form as a result of the oil-extraction technique.

You can read their full report on CIR's website. And if you're curious about the locations and magnitude of the many earthquakes California experiences each year, you can see that data in our Earthquake Tracker tool.