Oklahoma earthquake: M=5.6 quake shakes seven states

At 5:02 Saturday morning, a Magnitude 5.6 earthquake struck 14km NW of Pawnee, Oklahoma. This was a fairly shallow quake occurring about 6.59 km below Earth’s surface, and it caused strong shaking.

Based on early reports, the USGS estimates that there will be no casualties or major damage. However, some injuries or economic losses may still be possible.

熊本地震: M6地震がM7地震を誘発し,その後周辺の活断層にも影響が


How a M=6 earthquake triggered a deadly M=7 in Japan

It’s been over four months since we wrote about the powerful Kumamoto quake sequence: The 15 April 2016 Mw=6.2 (Mjma 6.5) Kumamoto, Japan, shock, which was succeeded 28 hours later by the very damaging Mw=7.0 (Mjma 7.3) shock on the same fault system. We can now give you a preview of crucial new discoveries by Japanese and other researchers.

Damage map of the Italy earthquake in Amatrice.

Italy earthquake: NASA radar maps reveal massive damage

Last week’s M=6.2 Italy earthquake left many parts of the medieval city of Amatrice in ruin. In the old part of the city, most buildings were made of unreinforced masonry, leaving them susceptible to collapse [Guidoboni and Valensise, 2015]. Amatrice was all but destroyed in three large shocks over 19 days in 1703, and so the part of the town that was highly damaged on 24 August 2016 was composed of buildings largely constructed about 300 years ago. In contrast, the newer construction in the east side of the town came through the M=6.2 quake relatively unscathed.


Living with Liquefaction

During intense earthquake shaking, water-saturated sediments can turn into a slurry (liquefaction), causing buildings, cars and other heavy objects lying on top of what were formerly stiff, dry sediments or …