Figure F1. Schematic view of the NEREID borehole geophysical observatory. Detailed descriptions of each component are given in "Installation Techniques". ROV = remotely operated vehicle; PAT = power supply access terminal; DTM = Department of Terrestrial Magnetism (Carnegie Institution of Washington) strainmeter; AGI = Applied Geomechanics, Inc., tiltmeter; CMG and PMD = seismometers.