Monthly Archives: September 2015

2015.09.16 Chile Update #3

The aftershocks continue and will do so for weeks. Aftershocks from the 2011.03.27 Tohoku-Oki M 9.0 earthquake continue today. The decay rate for seismicity relates to characteristics of the fault called the b-value. The b-value can be determined/modeled in several … Continue reading

Posted in College Redwoods, earthquake, education, geology, HSU, pacific, plate tectonics, subduction, tsunami

Chile Historic Tsunami Comparisons

Here are three tsunami wave amplitude models from NOAA for three Great (magnitude > 8.0) earthquakes in Chile. Here are the USGS websites for the three earthquakes that generated these earthquakes, plus the one from 2015.09.16 not shown on the … Continue reading

Posted in College Redwoods, earthquake, education, geology, HSU, pacific, plate tectonics, subduction, tsunami

2015.09.16 Chile Update #2

Here I post some updates about the M 8.3 Great Earthquake in Chile and the associated tsunami observations and models. I have three earlier posts about this earthquake and tsunami event. First Post Update #1 Tsunami Observations Here is an … Continue reading

Posted in Uncategorized

Chile M 8.3 Earthquake: Tsunami Observations!

Here are a couple of videos that document the arrival of tsunami waves in the “mouth of Genio river at Wafer Bay, Cocos Island, Costa Rica. Cocos Island is a National Park located between Galapagos Islands and the continental coast … Continue reading

Posted in College Redwoods, earthquake, education, geology, HSU, pacific, plate tectonics, subduction, tsunami

2015.09.16 Chile Update #1

Here are some updates to this earthquake and tsunami. First, here is an updated map. I have included an illustration from Atwater et al. (2005) that shows the earthquake cycle at a subduction zone. A subduction zone is a convergent … Continue reading

Posted in College Redwoods, earthquake, education, geology, HSU, pacific, plate tectonics, subduction, tsunami

Great Tsunamigenic Earthquake offshore Chile!

[Additional information is posted in a supplementary post here.] Well, I was in the middle of a Quaternary Stratigraphy lab when this hit, so it took a while to get home. My delay pales in comparison to the probably large … Continue reading

Posted in College Redwoods, earthquake, education, geology, HSU, pacific, plate tectonics, subduction, tsunami

Gulf of California Earthquakes! (first update)

Here is an update to the early morning post… I have prepared an updated map that shows the fracture zones, spreading ridges, transform faults, and basins in the region of seismicity from the past 24 hours. Here is the map. … Continue reading

Posted in College Redwoods, earthquake, education, Extension, geology, HSU, pacific, plate tectonics, San Andreas, strike-slip, Transform

Gulf of California Earthquakes! (first post)

We just had a few earthquakes in the Gulf of California (GOC). The results are early, so there is not a moment tensor plotted yet (updated map shows it now). The epicenters plot in the Farallon Baisn. The Gulf of … Continue reading

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

Earthquake in Papua New Guinea!

In the last ~24 hours, we have had a few earthquakes in northeastern Papua New Guinea, all in the M 5 range. Here are the USGS web sites for these earthquakes: 2015.09.11 M 5.5 2015.09.11 M 5.3 2015.09.12 M 5.0 … Continue reading

Posted in asia, College Redwoods, collision, earthquake, education, geology, HSU, Indonesia, pacific, plate tectonics, subduction, Transform

Kermadec trench earthquake!

Last night there were a few earthquakes along the Kermadec trench, which is a convergent plate boundary (subduction zone) where the Pacific plate subducts westward beneath the Australia plate. Here is the USGS website for this M 6.4 earthquake. Recent … Continue reading

Posted in College Redwoods, earthquake, education, geology, HSU, pacific, plate tectonics, subduction