Eastern Sierra Earthquakes

[SCPD]

We are currently experiencing a small swarm of earthquakes in the Mammoth Lakes area. The strongest of these earthquakes so far is listed as a 4.6 and located about 13 miles south of the town. This places the quakes in the Sierra Nevada and are most likely tectonic in origin, or related to the Sierra getting taller. The range is rising in elevation about 1.25" per one hundred years.

These earthquakes are not within the boundaries of the Long Valley Caldera, a feature of volcanic origin. The Caldera has been very quiet for 10 years now. It has been that long since we have felt a significant quake in the Mammoth area.

It is likely that some news media outlets will try to connect this latest swarm with volcanic activity, but if they do, they will be incorrect.

Not much on the scanner about this, although the 4.6 was strong enough to knock over a couple of knick knack stuff of the top shelf of a tall book shelf located on the second story of my condo. Most people in Mammoth, if they have been here for 10-30 years, are pretty used to this sort of activity and probably woke up, noted the time, and went back to sleep. Most are probably thinking, "here comes more inaccurate news reports of 'our volcano' getting restless!"

 

[Sac916]

Aside from local scanner traffic, are there any state or geological services to monitor after an earthquake?

We are currently experiencing a small swarm of earthquakes in the Mammoth Lakes area. The strongest of these earthquakes so far is listed as a 4.6 and located about 13 miles south of the town. This places the quakes in the Sierra Nevada and are most likely tectonic in origin, or related to the Sierra getting taller. The range is rising in elevation about 1.25" per one hundred years.

These earthquakes are not within the boundaries of the Long Valley Caldera, a feature of volcanic origin. The Caldera has been very quiet for 10 years now. It has been that long since we have felt a significant quake in the Mammoth area.

It is likely that some news media outlets will try to connect this latest swarm with volcanic activity, but if they do, they will be incorrect.

Not much on the scanner about this, although the 4.6 was strong enough to knock over a couple of knick knack stuff of the top shelf of a tall book shelf located on the second story of my condo. Most people in Mammoth, if they have been here for 10-30 years, are pretty used to this sort of activity and probably woke up, noted the time, and went back to sleep. Most are probably thinking, "here comes more inaccurate news reports of 'our volcano' getting restless!"

 

[linuxwrangler]

Aside from local scanner traffic, are there any state or geological services to monitor after an earthquake?

Start here:
http://quake.usgs.gov/recenteqs/latest.htm
http://quake.usgs.gov/waveforms/helicorder/index.html

 

[Big_Ears]

California has many ground installed seismic sensors all around the state, especailly at the active fault areas. Many of these sensors are maintained by the USGS and/or the CGS (CA Geological Survey). These sensors transmit real-time uplink telemetry data to satelites which downlink data to the USGS/CGS and/or recording/display sites like UC Berkeley/CalTech. etc. as part of the CISN (CA Integrated Seismic Network).

There are a couple sites located in adjacent public land next to my friend's ranch property located on Sunol Ridge. I watched as they installed/setup the seismic monitors. They dig a well sized hole. approx 50-60 ft below surface (in order to extract any surface motion) and installed sensitive 3-D ground acceleratmeters (motion sensors). The uplink site consists of a 3-element yagi antenna uplink aimed to the satelite. Power supplies are charged by a large solar panel which maintains the battery supply. The CGS/USGS tech that setup the station stated that very small movements (0.1-1 G's) are saved to memory and transmitted (in order to conserve power) in intervals, however larger ground movements are transmitted immediately after the event.