Geoscience and geohazard strain monitoring
Achieving high-resolution strain detection for geoscience and geohazard monitoring is made possible through the design of a novel instrument utilizing the MEMS strain sensor. The device ultra-precision capabilities provide the opportunity to detect incredibly small amplitude strain signals, anticipated to precede and accompany seismic events and volcanic eruptions.
The strain-meter comprises two primary components: a cement base responsible for transmitting strain to the sensors, and a cap constructed from plastic material housing the readout electronics. The base is formed by pouring cement into a mold. During installation, the strain-meter is positioned in the hole using a winch and filled with liquid cement, ensuring a robust mechanical connection between the base and the surrounding rock. The strain-meter base is made from the same material (cement) used to fill the hole, ensuring optimal mechanical coupling. Two silicon chips are affixed to the strain-meter base: one on the XY plane and another on the vertical side in the ZY plane. Each chip accommodates two MEMS sensors placed at 90° angles to each other. Consequently, the strain-meter incorporates a total of three MEMS sensors in the XYZ directions, along with an additional redundant sensor in the Y direction.
Deployment of the strain sensor within a drilling well situated at the base of volcano Etna