Magmatic dyke intrusion behind Saudi quakes of 2009, says US/Saudi study 26 September 2010Posted by admin in Middle East.
Tags: Saudi Arabia, Saudi earthquakes
Back in the late spring and summer of 2009 western Saudi Arabia was shaken by significant earthquake swarms: 30,000 quakes happened between April and June, prompting large-scale evacuations. The earthquakes happened in the Harrat Lunayyir volcanic field and were clearly related to active volcanism in some way, but the details remained unknown.
Now, however, a new study of the Harrat Lunayyir earthquake swarms by a joint United States/Saudi Arabian team of geologists has been published which concludes that ‘the earthquake swarm resulted from magmatic dyke intrusion’. The paper, ‘Broad accommodation of rift-related extension recorded by dyke intrusion in Saudi Arabia’, is available as an advanced online publication at Nature Geoscience (available to subscribers, that is). There’s also a news report of the study at AFP.
- John S. Pallister, Wendy A. McCausland, Sigurjón Jónsson, Zhong Lu, Hani M. Zahran, Salah El Hadidy, Abdallah Aburukbah, Ian C. F. Stewart, Paul R. Lundgren, Randal A. White & Mohammed R. H. Moufti, ‘Broad accommodation of rift-related extension recorded by dyke intrusion in Saudi Arabia’, Nature Geoscience, Published online 26 September 2010, doi:10.1038/ngeo966. [abstract]
P.S. Nature News reports on the study here, calling the Harrat Lunayyir event a ‘failed eruption’, which is a curious way of describing it. One might as well say it was a ‘successful magmatic intrusion’. Volcanism and related processes take many forms, and assuming that some forms are ‘successful’ (lava fountaining! extensive lava flows! success!) and others are ‘failed’ (nearly there, just arriving at the surface … no, not quite, a mere intrusion, oh what a failure) is not particularly relevant or helpful. It’s also notable that the term ‘failed eruption’ nowhere appears in the Pallister et al paper itself.
[Apologies for giving a duff link to the paper in the initial version of this post. I've now corrected the link.]
New study sheds light on Saudi volcano risk – AFP, 26 September 2010
Northwest Saudi Arabia vulnerable to volcanoes – ABC News, 26 September 2010
Failed eruption shook Saudi Arabia – Nature News, 26 September 2010
Global Volcanism Program: Harrat Lunayyir – information from the GVP on the area where the seismic activity has been located
Global Volcanism Program: Arabia – information from the GVP about the volcanoes of Arabia