The SOS module contains :
- (2) Absolute Pressure Gauges with available ranges of 700, 1400,
2000, 3000, 4000, and 7000 meters plus
- (1) Triaxial Accelerometer with an internal alignment
- (1) Digiquartz® Barometer, plus
- (3) Nano-resolution processing electronics.
- The pressure connection lines are vacuum oil-filled and can connect to a 3-way ball valve that switches between seawater pressures, (A), and an interior oil reservoir, (0).
Temperature compensated and linearized RS-232 outputs are provided from all sensors:
• Seawater pressures (A) and temperature readings from each pressure gauge (1 port)
• X-Y-Z plus total Vector accelerations and accelerometer temperature readings (1 port)
• Interior housing barometric pressures (0) and barometer temperature readings (1 port)
• All sensors can be synchronized and time-stamped using PPS inputs.
SOS Ocean Tests at the Monterey Accelerated Research System (MARS)
The University of Washington deployed the SOS module at MARS in mid-June of 2017. The colocated Triaxial Accelerometer and the 2 Absolute Pressure Gauges (APGs) make high-resolution
measurements of pressure and acceleration associated with earthquakes on land and in the ocean.
Shown below are the vertical and horizontal accelerations and the pressure changes associated
with the M8.1 Chiapas, Mexico earthquake on September 7, 2017.