Earthquake rate increases 50%

The USGS says the rate of earthquakes in Oklahoma has increased by about 50 percent, significantly increasing the chance for a damaging magnitude 5.5 or greater quake:

While it’s been known for decades that Oklahoma is ‘earthquake country’, we hope that this new advisory of increased hazard will become a crucial consideration in earthquake preparedness for residents, schools and businesses in the area.  Building owners and government officials should have a special concern for older, unreinforced brick structures, which are vulnerable to serious damage during sufficient shaking.

According to the USGS and the Oklahoma Geological Survey, statistical analysis shows that the quakes aren’t just a normal variation.  Waste water injection is a likely contributing factor.  The OGS has also  increased the number of seismic stations.