Earthquakes

Magnitude 5+ Earthquakes - Global

5.5 Earthquake hits Vanuatu.

5.5 Earthquake hits the Cook Strait, New Zealand.

5.2 Earthquake hits the Santa Cruz Islands.

5.0 Earthquake hits near the east coast of Honshu, Japan.

5.0 Earthquake hits Sumbawa, Indonesia.

Fracking Appears to Cause Quakes - USA

The deep injection into the ground of wastewater byproducts from hydraulic fracturing, or fracking, has caused a significant increase in U.S. earthquakes since the practice has recently become more widespread.

The U.S. Geological Survey (USGS) reports that there were more than 300 earthquakes above magnitude 3.0 from 2010 to 2012, which is a five-fold increase from the average number of 21 tremors per year measured from 1967 to 2000.

There are now more than 30,000 deep disposal wells in the country, typically injecting leftover fluids from fracking wells used for natural gas extraction.

And while the actual practice of fracking has not been found to cause any significant seismic events, the far deeper injecting of wastewater from the practice has.

Sometimes the water is blasted into deep, dormant faults. USGS geologist William Ellsworth says that even faults that have not moved for millions of years can be made to slip if conditions are right.

But he points out that only a few of the approximately 30,000 wastewater wells appear to have caused the increase in tremors.

Columbia University scientists caution that powerful earthquakes thousands of miles away can trigger swarms of minor quakes near injection wells as the arriving seismic waves help release the local built-up pressure.