Category Archives: strike-slip

Earthquake Report: Ridgecrest Update #2

Well Well Well The story continues to unfold. My original Earthquake Report for this widely felt sequence is here. My update #1 Earthquake Report for this widely felt sequence is here. Here is the Earthquake Engineering Research Institute (EERI) Learning … Continue reading

Posted in earthquake, education, geology, plate tectonics, San Andreas, strike-slip

Earthquake Report: Ridgecrest Update #1

My original Earthquake Report for this widely felt sequence is here. There have been well over 1000 aftershocks with magnitudes M ≥ 0.5. Last night there was the largest aftershock (so far) a magnitude M 5.4 earthquake. It is clear … Continue reading

Posted in earthquake, education, geology, San Andreas, strike-slip

Earthquake Report: Ridgecrest, CA

Well, happy fourth of July! There was a good sized earthquake in southern California today. The largest earthquake since the 1999 M 7.1 Hector Mine earthquake. (The 2003 San Simeon earthquake was larger, but much farther to the west, at … Continue reading

Posted in earthquake, education, geology, plate tectonics, strike-slip

Earthquake Report: Indonesia

I had been making an update to an earthquake report on a regionally experienced M 5.6 earthquake from coastal northern California when I noticed that there was a M 7.3 earthquake in eastern Indonesia. This earthquake is in a region … Continue reading

Posted in earthquake, education, Indonesia, New Zealand, pacific, plate tectonics, strike-slip, Transform

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. I didn’t realize this … 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: San Clemente Island

Well, yesterday was the start of a sequence of earthquakes offshore of San Clemente Island, about 100 km west of San Diego, California. The primary tectonic player in southern CA is the Pacific – North America plate boundary fault, the … Continue reading

Posted in earthquake, education, geology, pacific, plate tectonics, San Andreas, strike-slip

Earthquake Report: New Ireland

This region of Earth is one of the most seismically active in the past decade plus. This morning, as I was preparing for work, I got an email notifying me of an earthquake with a magnitude M = 7.5 located … Continue reading

Posted in earthquake, Extension, geology, landslides, pacific, plate tectonics, strike-slip, subduction, Transform, tsunami

Earthquake Report: Panamá

There was just now an earthquake beneath Panamá. The major plate boundary in the region is a subduction zone (convergent plate boudary) where the Cocos and Nazca plates dive northwards beneath the Caribbean plate forming the Middle America trench (MAT). … Continue reading

Posted in earthquake, education, geology, plate tectonics, strike-slip, Transform

Earthquake Report: Sulawesi, Indonesia

Today I awoke to the USGS earthquake notification service email about an earthquake offshore of Sulawesi, Indonesia. There was an earthquake with a magnitude M 6.8 to the southeast of the Donggala/Palu earthquake from 28 September 2018. Here is the … Continue reading

Posted in earthquake, education, geology, Indonesia, plate tectonics, strike-slip

18 April 1906 San Francisco Earthquake

Today is the anniversary of the 18 April 1906 San Francisco Earthquake. There are few direct observations (e.g. from seismometers or other instruments) from this earthquake, so our knowledge of how strong the ground shook during the earthquake are limited … Continue reading

Posted in earthquake, education, geology, los angeles, pacific, plate tectonics, San Andreas, strike-slip, Transform