Geologists say a fault in central Arkansas where hundreds of earthquakes have been recorded in recent months is longer and potentially more destructive than initially believed. 

Scientists had thought the fault is 3.7 miles long. Now they estimate it to be 6 to 7.5 miles long. Arkansas Geological Survey geohazard supervisor Scott Ausbrooks told the Arkansas Democrat-Gazette that the length is a concern because a longer fault could trigger bigger earthquakes.

More than 800 earthquakes have been recorded in the area in the past six months — including a 4.7 magnitude quake on Feb. 27 that was the largest earthquake recorded in Arkansas in 35 years.

Injection wells used by companies drilling for natural gas and thought to be connected to the quakes have been temporarily shut down.

 In the earth, a fault is a line of fracture in the rocks where the two sides move by each other. The movement can be up, down or sideways, and it is caused by pressure and tension in the rock. When a sudden movement happens along one of these fault lines, an earthquake happens.

A fault can be very small, it can be seen in a single quartz crystal, or it can be very long. The Great Rift Valley in east Africa is over 6000 miles long!

My biggest question is why they would allow them to drill on a fault line? 

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