This project will initiate long-term measurements of seafloor strain on the south Cleft segment of the Juan de Fuca Ridge. The measurements will be accomplished by arrays of instruments called acoustic extensionmeters that measure distances to neighboring instruments by precisely recording the round trip travel time of acoustic pulses. In this proof-of-concept phase, one 1.4 km array of 12 instruments will be installed at 100-200 m intervals using an ROV during the first field season. During the second and third field seasons data will be retrieved from a surface ship.
