Does Fracking Cause Earthquakes?

The controversial drilling technique known as fracking is linked to some real problems: air pollution, toxic waste, groundwater contamination and others.

You can now add one more problem to the list: earthquakes. Apparently, scientists have known for years that fracking causes earthquakes, but it hasn't been discussed much.

Now that thousands of earthquakes are rattling Oklahoma, Texas and other states, however, people are talking.