The objective of this installation is to monitor over long periods the mid-crustal deformation in a magmatic-seismogenetic dome of the Long Valley caldera in east-central California.

The instrument array included: 1c – strainmeter, pressure gauge and 2 stages of 3c seismometer (analogue) packages.

6 ¾” borehole, 110 °C static temperature, max. depth 2996 m, still operating

Sept. 1998: successful installation on steel rope, cables attached to rope with bands. Sensors in operation, strainmeter was lost shortly after installation.