econintersect.com
       
  

FREE NEWSLETTER: Econintersect sends a nightly newsletter highlighting news events of the day, and providing a summary of new articles posted on the website. Econintersect will not sell or pass your email address to others per our privacy policy. You can cancel this subscription at any time by selecting the unsubscribing link in the footer of each email.



posted on 12 November 2016

Earthquake Risk: Spotlight On Oklahoma

from CoreLogic

-- this post authored by Maiclaire Bolton

California is typically the first place that comes to mind when one thinks of earthquake activity in the U.S. In recent years, however, the central U.S. - especially Oklahoma, northern Texas and southern Kansas - has been getting more and more attention because of the rapid increase in earthquake activity. In fact, Oklahoma went from being a region of relatively low seismic activity to the state with the highest number of earthquakes per year nationwide in less than a decade.

The number of earthquakes at magnitude 2.0 or higher that have occurred in Oklahoma this year is nearly four times greater than California1, with Oklahoma experiencing 528 earthquakes of magnitude 3.0 or higher compared with 169 in California1 as of October 6.

This rapid increase in the number of earthquakes in Oklahoma and surrounding areas is highly correlated with oil and gas exploration, specifically the deep injection of waste fluid, a byproduct of the hydraulic fracturing process, commonly referred to as fracking.

As the rate of earthquake activity increases, the concern for this emerging risk grows. A 2016 study by the U.S. Geological Survey (USGS) shows that higher earthquake activity in Oklahoma has increased the seismic hazard of the region2.

It has been difficult to quantify this new hazard trend in Oklahoma since it is rapidly changing with an increasing number of earthquakes occurring year over year, which does not fit with the historical record that shows a consistently low rate of earthquakes for decades prior to the surge. As such, the USGS has developed an independent, short-term view of earthquake hazard specifically related to man-made, or induced, seismic activity3. This new study has led some to believe that earthquake hazard in Oklahoma is the highest in the nation.

While the majority of earthquakes that have occurred in Oklahoma continue to be small-to-moderate and non-damaging events, the threat of a larger, damaging earthquake remains. On September 3, 2016, residents of Oklahoma, Kansas and Texas were startled awake by the largest earthquake in Oklahoma’s history4 (Figure 2). At magnitude 5.8, this earthquake is also the largest to occur in the U.S. since the 2014 South Napa earthquake in California.

In order to understand how serious the recent spike in earthquake activity is, it is important to look at the rate of past earthquakes. Using data from the USGS, Figure 3 shows the rapid change in the rate of earthquakes in Oklahoma compared to California since 1970. Overall, there have been 19,480 earthquakes of magnitude 3.0 or higher in California compared with 2,299 earthquakes of the same magnitude in Oklahoma. The number of earthquakes in California has remained relatively constant over time, with the exception of years when a major earthquake occurred and the rate of earthquakes increased due to aftershocks following the event. On the other hand, Oklahoma experienced very low earthquake activity until 2009 when the rate began to rapidly increase. This increase is believed to correlate with increased oil and gas activity, specifically the pumping of waste water at fluid injection wells5.

Induced seismicity is a term that has become popular in recent years due to increased earthquake activity close to urban centers. But what is induced seismicity and what causes induced earthquakes? Unlike naturally occurring, or tectonic, earthquakes, induced earthquakes result from man-made or anthropogenic causes. Figure 4 illustrates the processes that can generate induced earthquakes.6 Both the injection or extraction of fluid into or from the ground can alter the pore pressure (i.e. the fluid pressure in the pores and fractures of rocks) of the subsurface. If the pore pressure is increased significantly, the imbalance in stresses can result in an earthquake. As pore pressure increases, the rate of earthquakes can also increase7.

As the number of earthquakes in Oklahoma continues to rise and the impact of the September 3 magnitude 5.8 earthquake is still fresh in the minds of many, there is a growing concern about the increased risk of induced seismicity. In general, the most frequent earthquake events are relatively small - mostly less than magnitude 4.0 - and would not be expected to cause damage. However, it is unknown how large and potentially damaging these earthquakes could become. In its 2016 report, the USGS indicates that it is possible for a larger, more damaging, earthquake to be triggered.

While the current rate of earthquakes is highest in Oklahoma and the short-term view of this hazard ranks the state with the highest hazard in the country, it is important to remember the long-term view of earthquake hazard and the population exposed to its threat. With its history of large damaging earthquakes and large populations exposed to the hazard, California still remains the top-ranked state for overall earthquake risk.

Source

http://www.corelogic.com/blog/authors/maiclaire-bolton/2016/11/earthquake-risk-spotlight-on-oklahoma.aspx

References:

  1. http://earthquake.usgs.gov/earthquakes/search/

  2. https://www2.usgs.gov/blogs/features/usgs_top_story/induced-earthquakes-raise-chances-of-damaging-shaking-in-2016/

  3. https://pubs.er.usgs.gov/publication/ofr20161035

  4. http://earthquake.usgs.gov/earthquakes/eventpage/ us10006jxs#executive

  5. McNamera, D.E., et al., 2015. Efforts to monitor and characterize the recent increasing seismicity in central Oklahoma. The Leading Edge. https://profile.usgs.gov/myscience/upload_folder/ ci2015Jun0413582855600McNamaraTLE.pdf

  6. http://esd1.lbl.gov/research/projects/induced_seismicity/

  7. Ellsworth, W.L., 2013, Injection-Induced Earthquakes. Science, vol.341. http://users.clas.ufl.edu/prwaylen/ GEO2200%20Readings/Readings/ Fracking/ Earthquakes%20and%20fracking.pdf

© 2016 CoreLogic, Inc. All rights reserved.

>>>>> Scroll down to view and make comments <<<<<<

Click here for Historical News Post Listing










Make a Comment

Econintersect wants your comments, data and opinion on the articles posted.  As the internet is a "war zone" of trolls, hackers and spammers - Econintersect must balance its defences against ease of commenting.  We have joined with Livefyre to manage our comment streams.

To comment, using Livefyre just click the "Sign In" button at the top-left corner of the comment box below. You can create a commenting account using your favorite social network such as Twitter, Facebook, Google+, LinkedIn or Open ID - or open a Livefyre account using your email address.



You can also comment using Facebook directly using he comment block below.





Econintersect Contributors


search_box

Print this page or create a PDF file of this page
Print Friendly and PDF


The growing use of ad blocking software is creating a shortfall in covering our fixed expenses. Please consider a donation to Econintersect to allow continuing output of quality and balanced financial and economic news and analysis.


Take a look at what is going on inside of Econintersect.com
Main Home
Analysis Blog
The Problem With Obamacare Is That It Did Little To Reduce Overall Healthcare Spending
Joan Robinson’s Critique of Marginal Utility Theory
News Blog
The Last Bucket Catch
Joe Sixpack's Situation in 3Q2016: The Average Joe Is Better Off
Why Are Some People More Delinquent On Loans Than Others? - Part 1
Gravity Returns To San Francisco Housing Market
Violent Bond Selloff: An Eye-Opening Perspective
Infographic Of The Day: Identity Theft: You Should Be Worried
Early Headlines: Russia Hacked GOP, Trump To Drain Energy 'Swamp'?, New Sec'y Of State Candidate, India IP Shrinks, India Has World's New Largest Solar Plant , China GDP Hides Volatility And More
Most Coup Attempts In Recent Years Have Failed
The Global Cost Of Diabetes
The Universities Churning Out The Most Billionaires
Five Amazing Ways Plants Have Created New Technologies
Where U.S. Weekly Wages Go The Furthest
What We Read Today 09 December 2016
Investing Blog
The New Art Of Utility Investing
Investing,com Weekly Wrap-up 09 December 2016
Opinion Blog
Trickle-down Economics, Trump Edition
Looking At Everything: Trump's $1 Trillion Infrastructure Plan
Precious Metals Blog
Silver Prices Rebounded Today: Where They Are Headed
Live Markets
09Dec2016 Market Close: Wall Street Closes On A New High, Trump Sugar High, Crude Prices Testing Resistance, US Dollar Melts Higher
Amazon Books & More






.... and keep up with economic news using our dynamic economic newspapers with the largest international coverage on the internet
Asia / Pacific
Europe
Middle East / Africa
Americas
USA Government



Crowdfunding ....






























 navigate econintersect.com

Blogs

Analysis Blog
News Blog
Investing Blog
Opinion Blog
Precious Metals Blog
Markets Blog
Video of the Day
Weather

Newspapers

Asia / Pacific
Europe
Middle East / Africa
Americas
USA Government
     

RSS Feeds / Social Media

Combined Econintersect Feed
Google+
Facebook
Twitter
Digg

Free Newsletter

Marketplace - Books & More

Economic Forecast

Content Contribution

Contact

About

  Top Economics Site

Investing.com Contributor TalkMarkets Contributor Finance Blogs Free PageRank Checker Active Search Results Google+

This Web Page by Steven Hansen ---- Copyright 2010 - 2016 Econintersect LLC - all rights reserved