SEMINAR: MGG Student Seminar Tuesday April 9

[Monica Arienzo <marienzo@rsmas.miami.edu>]

MGG Student Seminar
Tuesday April 9 - 12:00pm - CIMAS Conference Room

Qiong Zhang


Three-diemsinal seismic tomographY in Coso GEOTHERMAL FIELD: where is the heat source?


Abstract:
The Coso Geothermal Field is located at the west edge of the Basin and Range province and within the Eastern California Shearer Zone. Fumaroles are present along faults bounding the rhyolite-capped horst and locally within the rhyolite field. Due to the presence of the youth rhyolite lavas, hot springs and fumaroles, a magma body was proposed to be the source of thermal energy for the geothermal system. There is a discrepancy in identifying where the magma body exists among diverse geophysical and geological analyses. We apply the seismic tomography and earthquake relocation techniques to map the Vp, Vp/Vs variations underneath the geothermal field. The most striking feature of the resulting velocity model is that the low Vp, low Vs, low Vp/Vs anomaly exists between 6 and 12 km underneath the Coso Hot Springs accompanied by the ductile behavior shown by lack of seismicity. This could be interpreted to be the magma body in the vicinity of high temperature hot water system. The low Vp, low Vs, high Vp/Vs anomaly is observed from the surface to 3 km depth beneath the Sugarloaf Mountain, the largest rhyolite domes in Coso, which we interpret as the intrusive dike. The velocities in the top layers of our model are correlated with the surface geological features. The fault zones and basin areas, such as the Little Lake fault zone, the Airport Lake fault zone and the Indian Wells Valley show low-velocity anomalies. Our high-resolution velocity model images the detailed velocity structure beneath Coso and supports the existence of magma body in crust.


&

Putri Akmal


TBA

<<attachment: winmail.dat>>

---------------------------------------------------------------------
Seminars and symposia at RSMAS

To unsubscribe, e-mail: seminar-unsubscribe@lists.rsmas.miami.edu
For additional commands, e-mail: seminar-help@lists.rsmas.miami.edu
Post to: seminar@rsmas.miami.edu