The NEES@UCSB Wildlife facility was recently enhanced to include a unique cross-hole array experiment. The new permanent cross-hole array includes three geophones and a solenoid-activated dual-direction hammer source at 4.6 meters depth. And an additional geophones at 2.5m depth deployed directly above the 4.6m geophones in the casing furthest from the source. The system is set to trigger once per week automatically with both upward and downward hammer strikes, thus providing the capability to measure shear-wave velocity on a weekly basis. The system is also programmed to automatically activate the hammer source at shorter time intervals immediately following a large earthquake.
