Title: High-performance MEMS accelerometers for gravity mapping
Abstract: Silicon MicroGravity, Ltd. (SMG) is a new company based on research at Cambridge University on high-performance MEMS accelerometers. By means of resonant and mode-localized transduction, a silicon accelerometer is now able to measure Earth’s gravitational field to a resolution of 1 ppb. This breakthrough sensing capability has applications in the distributed gravitational “imaging” of large-scale geological features and infrastructure. This talk will describe SMG’s MEMS sensing technology and show how it can provide unprecedented levels of sensitivity in very harsh application environments. The initial target application, monitoring water penetration in oil fields, involves deploying MEMS gravity sensors down small-diameter boreholes. The high-resolution gravity measurements enable the remote monitoring of density variations in the surrounding formation at a distance of > 100 m from the well. The detection of fluid density variations precisely locates the moving water front, which is projected to lead to 1-2% increases in the yield of large reservoirs. Other applications include the monitoring of landslides and sub-surface carbon-storage facilities.