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,…
Earthquakes in Los Angeles
We have had a number of small earthquakes in the Los Angeles Basin in the past month. These three earthquakes appear aligned with the Newport Inglewood fault system, the fault that ruptured in 1933 for what is generally called the…
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…
New Britain and Bougainville: tectonic domains?
I was taking a looksie at the different moment tensors for the years of 2000, 2010, 2014, and March 2015. I noticed that the transform plate boundary on the eastern side of the South Bismarck plate may separate segments of…
New Britain trench seismicity: 2000 through March 2015
I have here placed the moment tensors for the large magnitude earthquakes along the New Britain trench for the time period from 2000 through March 2015. Note that the Mw 8.0 has a strike-slip moment tensor. There is a transform…
Northern Mid Atlantic Ridge: Charlie Gibbs fracture zone
We had a large Mw 7.1 earthquake today along the Charlie Gibbs fracture zone, which is the longest transform plate boundary fault system in the North Atlantic, which offsets the Reykjanes Ridge from the Mid Atlantic Ridge. Here is a…
Panama fracture zone strikes again
We have another earthquake along the Panama fracture zone (PFZ) plate boundary. There are numerous sub-parallel transform (strike-slip) faults in this region. The most recent earthquake is a M = 5.7 and is plotted as the most southerly orange dot…