Category Archives: geohazards

Friday Focal Mechanism: M 7.4, Oaxaca, Mexico

Posted on March 23, 2012 by Chris Rowan

The largest earthquake to hit the planet this week was in Mexico, which was shaken on Tuesday by a magnitude 7.4 earthquake. The epicentre was in the Oaxaca region about 300 kilometres southwest of Mexico city, and the rupture was … Continue reading →

Categories: earthquakes, focal mechanisms, geohazards

The humbling legacy of the Tohoku earthquake

Posted on March 13, 2012 by Chris Rowan

A year ago on Sunday, one of the biggest earthquakes ever recorded ruptured the subduction megathrust that dips beneath the east coast of Japan. The rupture displaced the seafloor by tens of metres and generated tsunami waves up to 20 … Continue reading →

Categories: earthquakes, geohazards, tectonics

Now that’s what I call a geomagnetic storm!

Posted on March 9, 2012 by Chris Rowan

It appears that I was a litte premature with yesterday’s post. Look at what happened to the ambient magnetic field at the two observatories at Boulder and Deadhorse today (the dotted line represents about where the plots I put up … Continue reading →

Categories: geohazards, geophysics, palaeomagic, planets

Geological mayhem and destruction in 2012: not the end of the world, just business as usual

Posted on January 1, 2012 by Chris Rowan

We don’t live on a boring planet. 2012 will be plagued by natural disasters, but so is every other year. Continue reading →

Categories: antiscience, climate science, earthquakes, geohazards, palaeomagic, public science, volcanoes

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 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

A short FAQ on earthquakes and fracking

Posted on November 9, 2011 by Chris Rowan

While there are plenty of important reasons to scrutinise this fracking business, the risk of triggering earthquakes is not one of them. Continue reading →

Categories: earthquakes, geohazards, public science

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