This poster shows a comparison of 1000 ft deep borehole Silicon Audio 203-60 sensor with geophones and a fiber distributed acoustic sensor (DAS).
We especially liked the quote below:
For microearthquakes, assuming frequency range of above 2 Hz, the SA-ULN sensor would be the ideal choice.Correa, et al. (2020) Exploring the limits of fiber-optic sensing in Cascadia: Borehole passive seismic monitoring using co-located DAS, low noise optical accelerometers, and geophones, Abstract 759800
The Seismometer to Investigate Ice and Ocean Structure (SIIOS) project is advancing the maturity of a commercial off the shelf (COTS) optical seismic sensor for spaceflight. The primary mission targets for SIIOS include landed spacecraft sent to the icy satellites in the outer solar system, including Europa. SIIOS will provide direct geophysical measurements that probe planetary ice-shell and ocean layers by exploiting terrestrially demonstrated methods. In terrestrial settings, active and passive seismic studies are used to measure ice thicknesses and to determine the nature of sub-glacial materials. Seismic surveys can also inform the vertical temperature distribution within ice, an important property for tidally heated icy worlds. The COTS instrument has been deployed and successfully operated in analog environments in the terrestrial cryosphere. Qualification for spaceflight, however, requires electronics upgrades, specifically to the commercial-grade control/conditioning electronics mounted in the sensor. We are also seeking to improve the sensitivity of the seismometer by lowering its noise floor. Here we present the upgraded capabilities of the SIIOS instrument. We also describe the work performed to advance the device to TRL 6 under NASA’s Instrument Concepts for Europa Exploration (ICEE) 2 program. P044-0018 - The Seismometer to Investigate Ice and Ocean Structure (SIIOS)