Can Oil Extraction Cause Earthquakes?

Fire boat response crews battle the blazing remnants of the off shore oil rig, Deepwater Horizon on April 21, 2010. The rig, located 51 miles southeast of Venice, Louisiana, exploded on April 20, 2010. CREDIT: USCG View full size image

While disagreement abounds on this topic, scientists at the U.S. Geological Survey (USGS) say that oil production can cause earthquakes, but not the kind reported in the news.

2004 quake that triggered a deadly tsunami in Sumatra, occur at plate boundaries where hard, rocky slabs slide against each other to release tremendous amounts of energy. Oil generally is found in permeable sediments that are soft and squishy, not in hard rock. When this squishy land moves, it releases a small amount of energy, which can lead to a "mini-seismic event"—one that is barely detected on the Richter scale.

Here's how it works: With high-tech equipment, oil companies pinpoint oil-rich areas and use large drills to puncture the surface below the sea, sometimes as deep as 10,000 feet. As this pricey fluid gets sucked from the sediment pores, the surrounding rocks shift positions to fill in the newly vacated spaces. At a large scale, for example the volume displaced when millions of barrels of oil are produced, the land movement can actually cause a mini-seismic earthquake, said Robert Morton, a USGS coastal geologist.

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