Category Archives: mendocino

Earthquake Report: Mendocino triple junction

Well, I was on the road for 1.5 days (work party for the Community Village at the Oregon Country Fair). As I was driving home, there was a magnitude M 5.6 earthquake in coastal northern California. https://earthquake.usgs.gov/earthquakes/eventpage/nc73201181/executive I didn’t realize … Continue reading

Posted in cascadia, College Redwoods, earthquake, education, geology, gorda, HSU, humboldt, mendocino, mendocino, pacific, plate tectonics, San Andreas, strike-slip, subduction, Transform

Earthquake Report: 2016 Summary Cascadia

Here I summarize the seismicity for Cascadia in 2016. I limit this summary to earthquakes with magnitude greater than or equal to M 4.0. I reported on all but five of these earthquakes. I put this together a couple weeks … Continue reading

Posted in cascadia, earthquake, education, geology, gorda, HSU, humboldt, mendocino, mendocino, oregon, pacific, plate tectonics, San Andreas, strike-slip, subduction, Transform, tsunami

Earthquake Report: Laytonville (northern CA)!

This morning there was another earthquake in northern CA between the San Andreas (SAF) and Maacama faults (MF). This region has been active for the past few years, with earthquakes in the M 3-4 range. Most recently, there was a … Continue reading

Posted in earthquake, education, geology, HSU, humboldt, mendocino, mendocino, pacific, plate tectonics, San Andreas, strike-slip, Transform

Earthquake Report: Mendocino fault!

Yesterday there was an earthquake along the eastern extension of the Mendocino fault system. This magnitude M = 4.1 earthquake (here is the USGS website for this earthquake) is a small magnitude, but it was widely felt. I was in … Continue reading

Posted in cascadia, earthquake, education, geology, gorda, HSU, humboldt, mendocino, mendocino, pacific, plate tectonics, strike-slip

Earthquake Report: Bartlett Springs fault system, Lake Pillsbury

We just had a good sized earthquake adjacent to the mapped surface trace of the Bartlett Springs fault, southeast of Lake Pillsbury. Here is the USGS website for the M 5.1 earthquake. Here is my interpretive map that shows the … Continue reading

Posted in earthquake, education, geology, HSU, humboldt, mendocino, plate tectonics, San Andreas, strike-slip, Transform

Earthquake Report: Mendocino fault and Gorda plate!

We just had an earthquake along strike with the Mendocino fault zone. This region is seismically active and there were a number of MF earthquakes in 2015. Here is the USGS web page for today’s M = 4.5 MF earthquake. … Continue reading

Posted in cascadia, College Redwoods, earthquake, education, geology, gorda, HSU, humboldt, mendocino, mendocino, plate tectonics, strike-slip

Cascadia subduction zone: Tectonic Earthquakes of the Pacific Northwest

IRIS and the US Geological Survey have recently produced an educational video about tectonic earthquakes in the region of the US Pacific Northwest. The project was funded by the National Science Foundation. The Video YT link for the embedded video … Continue reading

Posted in cascadia, College Redwoods, earthquake, education, geology, gorda, HSU, humboldt, mendocino, mendocino, oregon, pacific, plate tectonics, strike-slip, subduction, Transform, tsunami

Stress Changes from Strike Slip Faults

One may ask what are the relations between the Mendocino fault (MF) and the Cascadia subduction zone (CSZ). Earthquakes on both fault systems are responding to the same plate motions. As the Gorda plate moves to the east, relative to … Continue reading

Posted in cascadia, Chemeketa Community College, College Redwoods, earthquake, education, geology, mendocino, plate tectonics, San Andreas, subduction

Mendocino fault Aftershocks: Update

The aftershocks continue following the Mw 5.7 mainshock earthquake swarm along the Mendocino fault. Yesterday I plotted my interpretation for the location of the fault that this swarm may have ruptured upon. Some epicenters have been relocated and appear to … Continue reading

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

Mendocino fault earthquake 1/28/15 1:08 PM local time

We just had a good sized shaker, probably on the Mendocino fault system. Today’s earthquake occurred on 1/28/2015 at 1:08 local time. The mainshock, an earthquake of magnitude Mw = 5.7, has an epicenter approximately 20 km due west of … Continue reading

Posted in cascadia, Chemeketa Community College, College Redwoods, earthquake, education, geology, humboldt, mendocino, plate tectonics, San Andreas, Transform