Damaging Sichuan Earthquakes Now Linked to Fracking Operations

Damaging Sichuan earthquakes linked to fracking operations. (Image: via pixabay / CC0 1.0)

Two moderate-sized earthquakes that struck the southern Sichuan Province of China last December and January were probably caused by nearby fracking operations, according to a new study published in Seismological Research Letters. The December 2018 magnitude 5.7 and the January 2019 magnitude 5.3 earthquakes in the South Sichuan Basin caused extensive damage to farmhouses and other structures in the area.

The December earthquake was especially destructive, injuring 17 people and resulting in a direct economic loss of about 50 million Chinese Yuan Renminbi (roughly US$7.5 million). The Changning shale gas block in the South Sichuan Basin has been the site of fracking operations since 2010, with extensive horizontal fracking injection wells becoming more common since 2014. The earthquake rate in the Changning block rose dramatically at the same time that systematic fracking began.

Subscribe to our Newsletter!

Receive selected content straight into your inbox.

In the United States, wastewater disposal from oil and gas operations, where water produced during hydrocarbon extraction is injected back into rock layers, is thought to be the primary cause of induced earthquakes, especially in Oklahoma. However, there is growing evidence that hydraulic fracturing, or fracking, which uses injected water to break apart rock layers during hydrocarbon extraction may have caused moderate-size earthquakes at some sites in Ohio, Oklahoma, and western Canada.

Both wastewater disposal and fracking have induced earthquakes in the south Sichuan basin, says Xinglin Lei of the Geological Survey of Japan and his colleagues. In their new study in SRL, the researchers present “a full chain of evidence” to show that the December and January earthquakes were induced by fracking operations.

They pinpointed the location of the earthquakes, finding that they were relatively shallow (between 2 and 10 kilometers below the surface), as would be expected for induced earthquakes. The December and January quakes also coincided in time and space with injection at nearby fracking well pads. They did not have the exact injection volumes at these well pads to better understand the relationship between injection activities and the evolution of seismicity.

Lei and his colleagues’ modeling of seismic activity show that most of the activity came from the initial mainshocks, with little aftershock activity, which is also consistent with the pattern seen for induced earthquakes. Finally, their calculations show that overpressure on the rock pores, produced by the fracking injections, was strong enough to activate preexisting faults in the region. These faults were mostly unmapped and not in a favorable orientation to slip under normal tectonic activity, the researchers note.

Although he noted that their analysis did raise the possibility of seeing signs of fault reactivation from previous seismicity, Lei said:

The researchers say more information is needed about faults and their stress patterns in areas of the Sichuan basin surrounding fracking well pads, to guide drilling in a way that would avoid moderate seismic activity. Lei added:

Lei and his colleagues would like to see researchers, regulators, and oil and gas operators work together to better understand what causes injection-induced seismicity in the South Sichuan Basin to allow effective and safe fracking operations.

Provided by: Seismological Society of America [Note: Materials may be edited for content and length.]

Like this article? Subscribe to our weekly email for more!     

Recommended Stories

Artificial intelligence.

The Emergence of Artificial Intelligence and Its Benefit to Humanity

Every human has an innate nature that always seeks something that can improve everyone’s life ...

A martial artist practicing kung fu.

The Wisdom Behind Chinese Martial Arts

There is wisdom in Chinese martial arts. If you’ve always been curious about kung fu ...

Decluttering.

4 Reasons Why Decluttering Will Improve Your Mind, Body, and Soul

You’re not the only one who feels stressed out by a messy house, and the ...

Young woman looking longingly at chocolate pastries.

Is the Incentive for Emotional Eating the Same as for Binge Eating?

Finding comfort in food is quite common these days, and it is called emotional eating. ...

Chinese writing in a wok.

Most assume writing systems get simpler. But 3,600 years of Chinese writing show it’s getting increasingly complex

At this very moment, the words you are reading are entering your mind at the ...

The Fukushima Daichi Nuclear Power Station.

Fukushima Aftermath: Japan Set to Release Treated Radioactive Water into the Ocean

A top government spokesperson recently announced that Japan is taking steps toward discharging more than ...

The Oura ring.

How the Oura Ring Can Upgrade Your Health?

If you’ve heard about the Oura ring before, you aren’t the only one. This ring ...

A nuclear power plant.

Nuclear Fuel Alternatives After Fukushima Have Challenges Ahead

After the Fukushima disaster, research at The University of Manchester suggests that the preferred candidate ...

Painting of Antonio Straivari.

Stradivarius: The Most Valuable Violin You Can Own

Learning to play a musical instrument and becoming proficient at it is a skill that ...

Send this to a friend