Wednesday, September 21, 2011


Technically, Mammoth Mountain is not an active volcano. According to the Smithsonian’s Global Volcanism Program, “active” is a description reserved for volcanoes that have erupted in the last 10,000 years (the Holocene), and the last eruption from Mammoth Mountain was ~57,000 years ago1. Still, there are signs of hot magma inside Mammoth Mountain, and there was a swarm of small earthquakes within Mammoth Mountain in 1989. Scientists think the swarm resulted from a body of magma that rose up from deep in the earth and cracked rocks within the crust beneath mountain, but stopped before hitting groundwater and causing an eruption. This event is a good sign that there is still molten magma deep within the volcano, which could potentially be tapped for a future eruption. Also, large areas of trees killed by elevated levels of carbon dioxide in the soil from this magma lie on the SW side of Mammoth Mountain. Read More

Note: You are probably wondering why I am bringing up a article from back in May, well here it is, this is the station which is located at Mammoth Deep hole, it is one of several stations in that location.

You will see from the date, which is today a large earthquake was briefly registered which was followed by a small spike, the other stations have also picked this up. I can't find this earthquake listed anywhere, please do get in touch if you know where it has been logged.

There have been several earthquakes in Northern California which are not logged, normally they range from 1-2 Magnitude so they do not bother me as much as this one does.

At the top of this article you will see several stations located in Northern California all the MDH stations are located in the Mammoth region.

In addition the station on the right is Oat Mountain not far from Los Angeles i wrote about this station a few days ago as it was showing an increased seismic activity without any earthquakes being logged.

As you will see from today's graph they are still seeing activity today but not one earthquake has been logged in USGS for Northern California, they did however have a few of the "elusive ?" earthquakes appear for Northern California before quickly being removed again.

"Click on the Image to enlarge"