A 7.2 magnitude earthquake occurred about 250 km ENE of Kurli’sk, Russia. The earthquake occurred at a depth of 122.3 km (76 miles). There are currently no details on casualties.

Magnitude 7.2 KURIL’SKFriday, 19 April, 2013 at 03:05:53 UTC

Russia

Pacific

Russia

China

China

Shaking intensity

Strong shaking (VI) was recorded in the Kuril Islands, ~20 km to the south-west of the epicentre.

Modified Mercalli Intensity Scale (courtesy of University of Alberta)

Magnitude 7.2 KURIL’SKFriday, 19 April, 2013 at 03:05:53 UTC

USGS PAGER Population Exposed to Earthquake Shaking

Overall, the population in this region resides in structures that are a mix of vulnerable and earthquake resistant construction.

Recent earthquakes in this area have caused secondary hazards such as tsunamis and landsides that might have contributed to losses

Image courtesy of the US Geological Survey

Magnitude 7.2 KURIL’SKFriday, 19 April, 2013 at 03:05:53 UTC

Earthquake and historic seismicityThe earthquake epicentre (red star) is plotted on the map with regional historic seismicity since 1970 (grey circles).

Earthquakes of magnitude > 3 can be quite common in this region.

The Kuril Islands earthquake of 2006 (magnitude 8.3) is one of the largest earthquakes in recent times. It killed 11 people, and caused secondary hazards of landsides and tsunami.

Magnitude 7.2 KURIL’SKFriday, 19 April, 2013 at 03:05:53 UTC

Magnitude 7.2 KURIL’SKFriday, 19 April, 2013 at 03:05:53 UTC

Arrows show the direction of convergence between the Pacific and Okhotsk plates

Eurasia Plate

Pacific Plate

North America Plate

82 mm/yr

Tectonic summary

At the latitude of this earthquake, the Pacific plate converges with the North America plate towards the west-northwest at a velocity of approximately 82 mm/yr, and subducts beneath the Kuril Islands at the Kuril-Kamchatka trench.

This earthquake’s depth and source mechanism suggests that it might’ve occurred within the subducting Pacific plate.

USGS Centroid Moment Tensor Solution

The figure on the left shows the style of faulting (focal mechanism), and the right one shows schematically how plates associated with the normal faulting move.

Magnitude 7.2 KURIL’SKFriday, 19 April, 2013 at 03:05:53 UTC

Normal faulting

Seismogram recordings by school seismometers

Bishop Wordsworths School, Salisbury

Magnitude 7.2 KURIL’SKFriday, 19 April, 2013 at 03:05:53 UTC

Seismogram recordings by various seismometers across the UK

Magnitude 7.2 KURIL’SKFriday, 19 April, 2013 at 03:05:53 UTC

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Find out more….

• BGS (British Geological Survey) – seismology and earthquakes – frequently asked questions http://www.earthquakes.bgs.ac.uk/education/faqs/faq_index.html

• IRIS (Incorporated Research Institutions for Seismology) – learning about earthquakes http://www.iris.edu/hq/programs/education_and_outreach/students

• UK School Seismology Project – classroom activities, videos and support documents http://www.bgs.ac.uk/schoolseismology/home.html

• USGS (United States Geological Survey) – FAQs, glossary, posters, animations http://earthquake.usgs.gov/learn/

• USGS summary of the Kuril’sk earthquakehttp://earthquake.usgs.gov/earthquakes/eventpage/usb000gbf8#summary

Magnitude 7.2 KURIL’SKFriday, 19 April, 2013 at 03:05:53 UTC