There has been a lot of recent shake, rattle and rolling going on in Oklahoma, but according to William Andrews, director of the U.S. Geological Survey Oklahoma Water Science office in Norman, southwest Oklahoma has nothing to worry about.

Last week, Andrews spoke to the Greater Lawton Rotary Club, and told those in attendance that while there has been a noted increase in earthquake activity in northern and north central Oklahoma over the past few years, that the rest of the state is relatively safe. Andrews stated that the number of magnitude 3.0 earthquakes in the state has risen to over 500 in the last 3 years, but compared the earth's surface in those areas affected by these quakes as a "hard boiled egg with a cracked shell".

Speaking at the Wichita Room at Cameron University, Andrews went on to tell the group that each piece of the shell below the earth's surface is in constant motion, often colliding with or rubbing against each other. Its these interactions that more often than not aren't even recognized that cause quakes.

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Dr. Andrews spoke in front of the Lawton audience on the same day that Pennsylvania environmental regulators issued a report stating that there was a "strong correlation" between natural gas "fracking" and a series of minor earthquakes in the western part of the state last year.

Several quakes were recorded in April of last year in Lawrence county, an area about 50 miles north of Pittsburgh. The area is home to a natural gas well owned by Hilcorp Energy. Most of the quakes in the report were too weak to be noticed by the residents in the area, and no damage was reported.

The Hilcorp Energy Company, based in Houston, TX, is a known proponent of "fracking", a method used to extract gas or oil from underground shale rock. The method, known to be used by Hilcorp Energy in other wells, has previously been tied to earthquakes in Ohio and other neighboring states. This is the first instance of the method being tied to quakes in Pennsylvania, the 2nd leading producer of natural gas in the U.S. Hilcorp is reported to have discontinued fracking at the well after the quakes were reported.

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