Monthly Archives: April 2015

Earthquake in New Britain

Well, we just had a Mw 6.7 earthquake along the coast of New Britain. This region has been active lately… Here is the USGS web page for this earthquake. Here is a map showing the epicenter with Modified Mercalli Intensity … Continue reading

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

Updated Historic Seismicity: Nepal, Himalayas (3 data sets)

I have added one more polygon data set to the three main data sets that include records of historic earthquake slip patches. The three data sets now include Bilham (2004), Bettinelli et al (2006), and Berryman et al. (2009). I … Continue reading

Posted in Chemeketa Community College, collision, education, geology, HSU, plate tectonics

Surface Displacement and Ground Motion Maps: Nepal

I have taken a couple products and combined them in google earth to help us learn about the impact of the Nepal 2015.04.25 Mw 7.8 earthquake. Here is the link to the USGS web page for this earthquake. I provide … Continue reading

Posted in asia, Chemeketa Community College, collision, education, geology, HSU, plate tectonics

Nepal: PGA, DYFI, and the latest attenuation plot.

Well, data continue to come in. Below I plot the USGS Peak Ground Acceleration model results overlain upon the local map that I have been using to compare the current swarm of seismic activity with historic and prehistoric earthquake slip … Continue reading

Posted in asia, Chemeketa Community College, collision, education, geology, HSU, plate tectonics

Updated Historic and Prehistoric Maps

I have updated a couple of these maps and include a figure from a recent presentation given by Roger Bilham at AGU (2011). Here was my original and first updated posts about this earthquake and here is my first compilation … Continue reading

Posted in asia, Chemeketa Community College, education, geology, HSU, plate tectonics

Historic Earthquakes in the Himalayas

I have digitized some compilations of earthquake slip regions from a few papers and summarize these on the map below. The two main references are Bilham (blue; 2004) and Bettinelli et al. (orange; 2006). There are a couple of earthquakes … Continue reading

Posted in asia, Chemeketa Community College, collision, earthquake, education, geology, HSU, plate tectonics

Nepal Aftershock Region and Historic Earthquakes

Here is an updated map that shows the aftershocks following the devastating earthquake in Nepal. I have tentatively plotted the locations (epicenters) of some historic earthquakes in this region. Today’s earthquake ranks among the largest and approaches the size and … Continue reading

Posted in asia, Chemeketa Community College, collision, earthquake, education, geology, HSU, plate tectonics

Earthquake in Nepal!

We just had a large earthquake in Nepal! The moment tensor shows that this is a thrust/reverse (originally it was solved as a strike slip) earthquake. I will need to do a little more investigating about this tomorrow. (I am … Continue reading

Posted in asia, Chemeketa Community College, education, geology, HSU, plate tectonics

Mendocino fault Earthquake

This sure looks like an earthquake on the Transform Plate Boundary fault system known as the Mendocino fault. I have plotted the moment tensor for this earthquake. The shaking intensity contours are plotted. Here is the USGS web page for … Continue reading

Posted in cascadia, Chemeketa Community College, earthquake, education, geology, HSU, humboldt, mendocino, plate tectonics

Earthquake near Taiwan

Well, we just had a swarm of earthquakes with magnitudes near Taiwan. The USGS web pages for these earthquakes are here: M = 6.0, 6.1, and 6.4. This is a complicated tectonic region and there are many different and differing … Continue reading

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