Monthly Archives: February 2015

another earthquake in the east Java / Timor region of Indonesia

We had another earthquake in this region today. This is an interesting area of the world since this is a place where there is a transition between subduction to the west and collision to the east. The Island of Timor … Continue reading

Posted in Chemeketa Community College, College Redwoods, education, geology, Indonesia, plate tectonics, subduction

Indonesia Strikes Again

A deep earthquake has occurred probably within the downgoing Indo-Australia plate. The moment tensor shows oblique extension (part strike-slip, part normal). The depth aligns with the depth of the plate given the Hayes et al. (2012) slab models (which ends … Continue reading

Posted in Chemeketa Community College, College Redwoods, education, Extension, geology, Indonesia, plate tectonics, subduction

another northeast Japan earthquake in the Tohoku-Oki earthquake region

We have had another small aftershock. Here is the USGS web page for this earthquake. This time it is in a different region than the swarm of the past couple of weeks. Earlier posts: My first post The aftershocks continue … Continue reading

Posted in Chemeketa Community College, College Redwoods, earthquake, education, geology, Japan, plate tectonics, subduction

Gorda plate earthquake 2015.02.24

Where else would we get a focal mechanism or moment tensor for an earthquake of such a small magnitude! We are so lucky. This is the USGS web page for the earthquake. We get Gorda plate earthquakes frequently and most … Continue reading

Posted in cascadia, Chemeketa Community College, College Redwoods, education, geology, humboldt, plate tectonics

Tohoku-Oki aftershocks are in a region of low slip during main events in 2011

Here is what I was getting at in my last post. I have taken the Ammon et al. (2011) slip model and placed it into a real world reference frame (rubbersheeted it in ArcGIS). Then I exported it as a … Continue reading

Posted in Chemeketa Community College, earthquake, education, geology, Japan, plate tectonics, subduction

Tohoku-Oki Aftershocks Continue

The aftershocks continue offshore northeast Japan. The recent swarm appear to align along a northwesterly strike (trend). Here is the USGS web page for the earthquake from today. This is the USGS web page for the largest magnitude earthquakes in … Continue reading

Posted in Chemeketa Community College, education, geology, Japan, plate tectonics, subduction, sumatra, tsunami

Japan earthquake may be aftershock to 2011 Tohoku-Oki earthquake

The USGS depth has been updated to 23.3 km. Now we may interpret this to be an interface earthquake. Here is my first post about this earthquake and here is a post about some aftershocks. Here is a map showing … Continue reading

Posted in Chemeketa Community College, earthquake, education, geology, plate tectonics, subduction, tsunami

NE Japan aftershocks continue offshore the Sanriku coast

There continue to be aftershocks in the M 4-5 range. These are aftershocks and triggered earthquakes (if they are generally on different faults) from the Mw 6.7 earthquake. Here is my page on this mainshock and here is the USGS … Continue reading

Posted in Chemeketa Community College, earthquake, education, geology, plate tectonics, subduction, tsunami

Sandwich Earthquakes in Scotia, mmmmm

We have had a swarm of earthquakes near the Sandwich Islands along the Scotia subduction zone, an oceanic subduction zone. Here is the USGS web page for this earthquake. Here is a map showing the regional tectonic setting with relative … Continue reading

Posted in Chemeketa Community College, education, geology, plate tectonics, subduction, tsunami

Earthquake offshore of the Sanriku Coast

We just had a good sized shallow compressional earthquake in the northern part of the 2011 Tohoku-Oki earthquake slip region. The USGS web page lists the magnitude at Mw 6.7. Here is a great summary of the tectonics of this … Continue reading

Posted in Chemeketa Community College, earthquake, education, geology, subduction, tsunami