Showing posts with label tremor. Show all posts
Showing posts with label tremor. Show all posts

Monday, September 30, 2013

Earthquake hits Laptev Sea

An earthquake with a magnitude of 4.6 on the Richter scale hit the Laptev Sea on September 28, 2013.

[ click on image to enlarge ]
This follows a number of earthquakes on or close to the fault line that crosses the Arctic Ocean and extends into Siberia, as shown on above map and on the map below.

[ click to enlarge ]
Furthermore, as earlier discussed in the post Methane release caused by earthquakes, there has been a lot of seismic activity in the Aleutian Islands region all the way up into Alaska, including an earthquake with a magnitude of 7 on the Richter scale on August 30, 2013, and several more recent earthquakes with a higher magnitude than 6 on the Richter scale.

This is a lot of seismic activity for the Arctic, given that this is a relatively quiet part of the globe in terms of earthquakes.

[ click on image to enlarge ]
As above map shows, there were 1250 earthquakes with a magnitude of 2.5 or higher over the past 30 days globally. About 90% of the world's earthquakes occur along the Ring of Fire, on the edges of the Pacific Ocean.

The fault line that crosses the Arctic Ocean marks the boundery between the North American Plate and the Eurasian Plate. Along this fault, huge amounts of methane are held in sediments, in the form of free gas and hydrates. The danger is that earthquakes along this fault will destabilize methane, causing it to rise abruptly in large amounts and enter the atmosphere.

As the top image shows, a lot of methane is currently present in the atmosphere along this fault line. Methane has shown up there repeatedly, indicating that methane there has been prone to release for some time and warning that even larger releases could occur soon.

Related posts

- Methane release caused by earthquakes (2013)
http://arctic-news.blogspot.com/2013/09/methane-release-caused-by-earthquakes.html

- North Hole (2013)

- Sea of Okhotsk (2013)
Methane-hydrates.blogspot.com/2013/06/sea-of-okhotsk.html

- Seismic activity, by Malcolm Light and Sam Carana (2011)
Arctic-news.blogspot.com/p/seismic-activity.html

- Thermal expansion of the Earth's crust necessitates geoengineering (2011)
Arctic-news.blogspot.com/p/thermal-expansion.html