Micro-Earthquake At Long Valley Caldera Geothermal Area (Stroujkova & Malin, 2001)

GEOTHERMAL ENERGY

=====

Exploration Activity: Micro-Earthquake At Long Valley Caldera Geothermal Area (Stroujkova & Malin, 2001)

Exploration Activity Details
Location	Long Valley Caldera Geothermal Area
Exploration Technique	Micro-Earthquake
Activity Date	- 2001
Usefulness	not indicated
DOE-funding	Unknown

Notes

"Our preferred model for the unusual events is that of multiple ordinary earthquakes being triggered or forced by a fluid injection into a thin volcanic conduit. An example of such a structure would be a dike connected to one or more shear or wing fractures. In this model, resonant increases in pressure in the conduit would cause the shear fractures to fail seismically at fixed time delays. For the time delays seen at Long Valley, the dimensions of the conduits would be on the order of 24�74 m. Existing models of such a conduit's resonances show that they are highly damped (e.g. Ferrick et al., 1982), and thereby likely to produce only a few shear failures. We speculate that, with continued action of the triggering process, the sub-events could evolve into observable volcanic tremors at Long Valley."

References

• A. Stroujkova, P. Malin (2001) Multiple Ruptures For Long Valley Microearthquakes- A Link To Volcanic Tremor(Question)