Andreas Späth

Does fracking cause earthquakes or not?

2013-07-23 07:36

Andreas Späth

Last week I asked (and tried to answer) the question whether or not fracking causes groundwater pollution. Another issue that's been in the news lately and one that causes a fair amount of confusion concerns the connection between the controversial oil and gas extraction method and earthquakes.

On one level, the answer to this one is straight forward enough: yes, fracking does cause earthquakes. In simplistic terms, the pressurised fluids injected into fracking wells lubricate pre-existing but dormant fault planes and thus increase the likelihood that they rupture, causing two adjoining bodies of rock to slide and grind past each other and the ground above to shake.

But that only addresses part of the matter. The more pertinent concern is how severe these fracking-related seismic events are.

In 2011, the British Geological Survey confirmed that two earth tremors near Blackpool in North-West England were most likely to have been the result of exploratory shale gas drilling operations employing fracking in the area and the company doing the drilling, Cuadrilla Resources, accepted responsibility for the events.

Causing earthquakes

The quakes in question were very weak, however, with magnitudes of 2.3 and 1.5 on the Richter scale respectively, and they caused neither damage nor injuries.

A recent study by a group of British scientists identified merely three earthquakes caused by human activity that could be attributed to fracking since 1929 - one each in the USA, Canada and the UK. The largest of these occurred in the Horn River Basin in Canada and had a magnitude of 3.8.

While the study "established beyond doubt" that fracking can indeed cause earthquakes, the lead author, Professor Richard Davies of Durham University concluded that it's not a significant mechanism for inducing tremors that can actually be felt by anyone other than a seismologist using fairly sensitive measuring equipment.

So if fracking is ever going to happen in South Africa, a direct increase in earthquakes powerful enough to cause damage or injury is not something we should worry about a whole lot. Which is, of course, not the same as saying that fracking won’t cause damage and injury in a number of other ways - it will!

But this is not quite the end of the story. While fracking itself is not a major inducer of dangerous earthquakes, a closely associated activity may well be.

Fracking produces millions of litres of wastewater in the USA every year and a lot of that waste is disposed of by pumping it into deep underground wells. Over 150 000 of these injection wells are now in operation in the country to get rid of wastewater from the oil and gas fracking operations.

This practice (which is illegal in the EU) has been directly linked to significantly more severe earthquakes than those caused by fracking itself. In 2011, for example, a 5.7 magnitude tremor in Oklahoma believed to be caused by injection wells for fracking wastewater was felt in 17 states, destroyed 14 homes and injured two people.

In Arkansas, earthquakes of magnitude 2.5 and larger have increased drastically since similar injection wells became operational in 2009 (up from just one in 2007 to 157 in 2011) and 98% of them occurred within 6 kilometres of three wells after wastewater injection started.

The verdict

In the whole of the American Midwest, in what should naturally be a tectonically stable region, "a remarkable increase" in the rate of earthquakes of magnitude 3 and higher has been documented since the fracking boom took off there.

This month, researchers showed that in areas that have undergone extensive underground injection of fluids, significantly tremors can be triggered by much larger earthquakes thousands of kilometres away. The event in Oklahoma I mentioned above, for instance, is likely to have been set off by a magnitude 8.8 quake in Chile.

So what's the verdict in a nutshell?

Current scientific opinion suggests that fracking in and of itself is unlikely to cause dangerous earthquakes. If, however, large quantities of wastewater from fracking operations are injected into disposal wells, the area in question is likely to become susceptible to more powerful and potentially damaging earthquakes.

- Andreas is a freelance writer with a PhD in geochemistry. Follow him on Twitter: @Andreas_Spath
Send your comments to Andreas

News24 encourages freedom of speech and the expression of diverse views. The views of columnists published on News24 are therefore their own and do not necessarily represent the views of News24.

- News24


The testimony that sunk him

2014-04-18 07:00

Read News24’s Comments Policy publishes all comments posted on articles provided that they adhere to our Comments Policy. Should you wish to report a comment for editorial review, please do so by clicking the 'Report Comment' button to the right of each comment.

Comment on this story
Add your comment
Comment 0 characters remaining

Inside News24

  • Thursday Sir Lowry's Pass - 05:35 AM
    Road name: Old Sir Lowrys Pass Road
    TRAFFIC LIGHTS not working at Bezweni Road
  • Thursday Cape Town - 05:35 AM
    Road name: Buitengracht Street
    TRAFFIC LIGHTS not working at Waterkant Street
More traffic reports...

Jobs in Cape Town [change area]

Property [change area]

Travel - Look, Book, Go!

Escape winter, head to Mauritius

Escape winter by spending 7 nights in Mauritius' tropical bliss from R13 215 per person sharing. Includes return flights, airport transfers and accommodation. Book now! - shop online today

Get many eggs in one basket!

Gaming bundles: 2 Super Hits games for R99, 3 Disney games for R99 and more + exclusive accessory bundles only available on While stocks last. Shop now!

25% off bestselling books!

The Real Meal Revolution by Tim Noakes, Jeffrey Archer’s Be Careful What You Wish for, Man’s Search for Meaning by Victor E. Frank and many more titles. Shop now!

Up to 25% off electronics

Buy top electronics and save up to 25%. Such as’s 1# selling product the gobii eReader, Patriot X Porter flash drive, Asus Nexus 7” 3G tablet, Samsung Galaxy SIII, Lenovo G580 Notebook and many more. Shop now!

DStv HD PVR Decoder now R949

The DStv HD PVR Decoder has further revolutionised the television experience with lifelike viewing, sharper images, more vibrant colours and precision picture quality. Now R949, save R550. Offer valid while stocks last. Shop now!

Up to 30% off appliances & homeware

Save up to 30% on appliances and homeware this Easter! Offer valid while stocks last. Shop now.

OLX Free Classifieds [change area]

Samsung Galaxy s4

Mobile, Cell Phones in South Africa, Western Cape, Cape Town. Date October 24

Best bargain in big bay

Real Estate, Houses - Apartments for Sale in South Africa, Western Cape, Cape Town. Date October 25

VW Golf 6, 1.6 Trendline (Excellent condition)

Vehicles, Cars in South Africa, Western Cape, Cape Town. Date October 25

BlackBerry Bold Touch 9900

The Blackberry Bold Touch 9900 is as the name says...

From R3565.00

I'm shopping for:


Self-indulgence may be strong today. You may want to enjoy yourself to the fullest and share it with those that make you more

There are new stories on the homepage. Click here to see them.


Create Profile

Creating your profile will enable you to submit photos and stories to get published on News24.

Please provide a username for your profile page:

This username must be unique, cannot be edited and will be used in the URL to your profile page across the entire network.


Location Settings

News24 allows you to edit the display of certain components based on a location. If you wish to personalise the page based on your preferences, please select a location for each component and click "Submit" in order for the changes to take affect.

Facebook Sign-In

Hi News addict,

Join the News24 Community to be involved in breaking the news.

Log in with Facebook to comment and personalise news, weather and listings.