I put together an animation that includes the seismicity from 1/1/2000 until 6/1/2015 for the region near the Blanco fracture zone, with earthquake magnitudes greater than or equal to M = 5.0. The map here shows all these epicenters, with…
New Britain Strikes Again!
In the past week, there has been a series of earthquakes in the New Britain trench. The largest quakes are M = 6.7 & 6.8. Now we might call those foreshocks to today’s M = 7.5 earthquake de Cinco de…
Small Earthquake in San Francisco Region
There was a M 3.6 earthquake near Concord, CA. This earthquake was felt widely across the S.F. Bay area. The two earthquakes plotted in the map below are both just southeast of the 2014 August Napa earthquake. The Napa earthquake,…
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…
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…
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…
Earthquake in Crete
We just had a M = 6.0 earthquake in Crete. Here is the USGS web page for this earthquake. This is an interesting region tectonically. The convergence of the Africa-India-Australia plates northwards towards the Eurasian plate runs from west of…
Earthquake in the Baldwin Hills (Los Angeles)
Well, there was quite a buzz on social media following this small magnitude earthquake today. Here is the USGS web page for this Mw 3.3 earthquake. The earthquake appears to be related to the Newport-Inglewood fault system and the epicenter…
Blanco fracture zone strikes again
The Blanco fracture zone (BFZ) is a transform plate boundary that connects the Juan de Fuca ridge with the Gorda rise spreading centers. This active fault zone consists of numerous right-lateral (dextral) faults. There is some debate as to how…
Mendocino fault earthquake
We had a small magnitude earthquake “today” along the Mendocino fault system approximately 150 km west of Cape Mendocino. Here is the USGS web page for the Mw 4.8 earthquake. Based upon the tectonic setting, the hypocentral depth, and the…