This week's series of micro-quakes near Hawthorne, Nevada, where last year's large quake swarm occurred. Researchers are looking at this area closely.
In the center of this map, you see an area north of a large lake, and between two major faults. This is a series of micro-quakes within Joshua Tree National Park, and an area linking two spreading zones. Notice the numerous parallel faults to the north of the quakes, which is typical of a spreading zone, and the parallel faults to the south, which is the same thing. The San Andreas fault is the one on the north side of the lake, and is a transform fault coming off the Salton rifting system.
Here is the waveform of a 2.0 micro-quake today, in the area north of the San Andreas Fault, and in an area linking two spreading zones. It has the appearance of an angry cat's tail, which is a possible indicator of fluid and semi-fluid high pressure matter in motion underground. Sometimes that can be magma. One can tell by measuring the release of Co2 and other gases.
Today, and this week, we are witnessing two areas of micro-quakes in areas of known previous volcanism, and possible magma chambers below ground.
One is near Hawthorne, Nevada, just east of Mammoth Lakes, CA. This is an area that had experienced thousands of micro-quakes and dozens of moderate earthquakes just last year, and it became the concern of researchers and geologists. Here is the University of Nevada's website concerning research being done about last year's earthquake series near Hawthorne.
The next series of earthquakes occurred today within Joshua Tree National Park, and are more wide spread than the current series near Hawthorne. I'm making a note on this, and it's not an alarming note at all. The reason for mentioning it, is the fact that these micro-quakes are in a rifting zone, and an area that wants to link the northern end of the East California Shear Zone with the Salton Trough Rift Valley. I believe that this what the Mojave Young Volcano System is all about, a link between two spreading zones.
In simple words, a rifting zone exists in Eastern California and Southern California, and it's trying to find a way to link up fully, and fully be a spreading zone - and some of that activity takes place as the Mojave Young Volcano System. Two tectonic plates are moving away from each other in this area, thus causing for basalt magmas to try and surface.
This waveform you see here is a fine example of a possible near surface volcanic micro-quake. I can't confirm this, but can give an educated guess. It would require a team of researchers to confirm that this is indeed volcanic in nature.