Some news for a busy Tuesday:
The crater at Poas volcano in Costa Rica, taken February 25, 2010. Image courtesy of OVSICORI by Federico Chavarria.
After the MSNBC debacle, it is nice to see some good articles on why the Chilean earthquake was overall less disastrous than the Haitian earthquake, why the tsunami wasn't as large as predicted and why these earthquakes are not abnormal. There are a lot of factors involved - the location, depth, preparedness, wealth - so the comparison can be very telling in terms of both geologic and societal issues.
The other scientific fallout from the Chilean earthquake will be a test of the volcano-earthquake connection suggested by Sebastian Watt in last year's EPSL article. According to Watt's (and others) research, we should expect to see an uptick in volcanic activity over the next year within 500 km of the epicenter of the earthquake - so watch places like Longavi, Descabezado Grande, Calabozos, Copahue, Chillan and Lonquimay amongst many others.
Remember the spiders on Mt. Saint Helens, used to monitor the volcano? Well, they will be spreading to Chile to help monitor Chaiten. Two spiders will be set up on the rhyolite dome system to monitor changes in the domes - looking at seismic activity, deformation and explosions in the caldera.
Dr. Boris Behncke has updated us on some of the volcanic activity in Costa Rica - including a phreatic eruption at Poas last week and increasing seismicity at Irazu. More on the earthquakes at Irazu can be read here. There is also a great set of aerial images of Poas and Arenal taken recently that were posted by OVSICORI.
Eruptions reader Thomas Wipf left a link to a great video of Sakurajima in Japan erupting on January 16, 2010. Definitely worth the four minutes to see an impressive explosive eruption.
It seems that activity at Mayon has settled down significantly as well, with PHIVOLCS lowering the alert status to Level 1 (of 3). Only about 5 volcanic earthquakes are occurring daily at Mayon and that the overall activity suggests a return to "normalcy". However, they do warn people to be careful in lahar-prone drainages near the volcano considering all the new, loose volcaniclastic material on the slopes of Mayon.
