Category Archives: focal mechanisms

Two more earthquakes shake Christchurch

Posted on December 23, 2011 by Chris Rowan

Just as it seemed that seismic activity was finally dying down in Christchurch, the city has been shaken by two more earthquakes. The USGS currently has the first shock pegged as a magnitude 5.8, and the second as a magnitude … Continue reading →

Categories: earthquakes, focal mechanisms, geohazards

Friday(ish) Focal Mechanism: a kinky slab beneath Mexico

Posted on December 17, 2011 by Chris Rowan

A quick look this week at the magnitude 6.5 earthquake that shook southern Mexico last Sunday. It caused a fair amount of shaking in Mexico City, and a few deaths, but apparently no major structural damage. The depth of the … Continue reading →

Categories: earthquakes, focal mechanisms, tectonics

Friday focal mechanisms: aftershocks in eastern Turkey

Posted on November 11, 2011 by Chris Rowan

Almost a fortnight after a magnitude 7.1 earthquake shook Eastern Turkey, the region continues to suffer from aftershocks, and there were two pretty big ones earlier this week: a magnitude 5.2 on Tuesday, and then a magnitude 5.6 on Wednesday. … Continue reading →

Categories: earthquakes, focal mechanisms, geohazards

The Oklahoma Earthquakes

Posted on November 7, 2011 by Chris Rowan

There was some slight seismic excitement over the weekend in central Oklahoma: a magnitude 4.7 earthquake shook things up early on Saturday morning, which turned out to be the prelude to magnitude 5.6 tremor late Saturday evening. The focal mechanisms … Continue reading →

Categories: earthquakes, focal mechanisms, tectonics

M 7.2 earthquake near Van, eastern Turkey

Posted on October 23, 2011 by Chris Rowan

Earlier this morning, a magnitude 7.2 earthquake hit near the city of Van on the eastern border of Turkey. The BBC reports that at least 45 people have died as buildings collapsed close to the rupture. The most well-known seismic … Continue reading →

Categories: earthquakes, focal mechanisms, geohazards, tectonics

Friday Focal Mechanisms: the Hayward Fault shows up to the Shakeout Party

Posted on October 21, 2011 by Chris Rowan

Yesterday, several million Californians participated in the 2011 Great California ShakeOut – a simulated earthquake drill, held close to the anniversary of the 1989 Loma Preita earthquake, that aims not only to raise awareness of the ever-present risk of a … Continue reading →

Categories: earthquakes, focal mechanisms, geohazards

Friday focal mechanism: mountain building in Argentina

Posted on October 7, 2011 by Chris Rowan

Yesterday a magnitude 6.2 earthquake struck in the Jujuy province of northwestern Argentina, in the western foothills of the Andes. What few news reports there are indicate strong shaking but little damage in what seems to be a remote and … Continue reading →

Categories: earthquakes, focal mechanisms, geohazards, structures

Seismo-volcanism in Eritrea

Posted on June 22, 2011 by Chris Rowan

The Great Rift Valley marks where East Africa is slowly attempting to break away from the rest of the African continent, at a rate of less than a centimetre a year. At the north-eastern end of the rift, where it … Continue reading →

Categories: earthquakes, focal mechanisms, tectonics

More large aftershocks rattle Christchurch: will it ever end?

Posted on June 13, 2011 by Chris Rowan

Analysis of the ongoing earthquake sequence. Continue reading →

Categories: earthquakes, focal mechanisms, geohazards, tectonics

Earthquake location matters, part eleventy

Posted on April 12, 2011 by Chris Rowan

It’s been a month since the Tohuku earthquake and tsunami rattled then swamped northern Honshu, and Japan continues to be rattled by sizeable aftershocks. A magnitude 7.1 shock last Thursday initially set off further tsunami alerts but the rupture turned … Continue reading →

Categories: earthquakes, focal mechanisms, geohazards, society