Is there more evidence linking fracturing and injection wells with earthquakes? According to a few recent headlines, evidence may be building.

Texas

According to DallasNews.com, more than 30 earthquakes have hit near Azle, Texas, a town about 20 miles northwest of Fort Worth.

The residents of the town voiced concerns about the quakes during a meeting with the Texas Railroad Commission. The Railroad Commission regulates the state’s oil and gas industry.

What’s causing the quakes? Many residents believe they’re stemming from deep injection wells used to dispose water from natural gas drilling.

Though residents were expecting answers, non were given by the commission. Studies from state geologists are being conducted.

Feel the earth move in Oklahoma

The Texas quakes aren’t the only earth-shakers making headlines. NPR recently aired a story about the sharp rise in earthquakes in another state that has an active natural gas and oil industry: Oklahoma.

Listen to the story

According to NPR, Oklahoma averaged about 50 earthquakes a year. But the past few years have seen a large increase. In 2013 the state experienced almost 3,000.

Though the quakes are usually small, one quake in 2011 registered a 5.6 magnitude.

According to scientists with the U.S. Geological Survey, there’s evidence the quakes are related to the state’s oil and gas industry, but there’s no solid proof.

Another quake was felt in Oklahoma, near Prague, Okla., on January 8.

What can cause quakes?

In the case of the 2011 quakes that rattled Youngstown, Ohio, a deep injection well, known as Northstar 1, was to blame.

It was reported in the July 2013 issue of the journal Geophysical Research Letters, that Youngstown’s first quake occurred 13 days after the deep injection well began pumping waste water into the ground.

Dips in earthquake activity also coincided with holidays, holidays when the well would be brought offline like Memorial Day, the Fourth of July and Labor Day.

It was found that the quakes were caused by the wastewater essentially lubricating an ancient fault near the injection well.

Though the researcher, Won-Young Kim, a seismologist at Columbia University, was quick to point out that the quakes were not caused by fracking.