Semiconductor Strain Gauge Based Pressure Transducer for Use in Borehole Seismics

40837 November 13, 1996 TomoSeis, Inc. Crosswell Seismic Imaging holds great promise for imaging the region between existing oil wells to incrementally increase the recovery of the 368 billion barrels of oil still in the ground (of the 500 billion barrels of original oil in place in the U.S.). To make crosswell data acquisition cost effective, surveys must be acquired at greater well spacings than currently and receiver tools must be operated inside of production tubing, in order to avoid the cost and risk of pulling production tubing to run crosswell surveys. However, the impediment to operation at greater well spacings and inside of production tubing is insufficient signal-to-electronic-noise ratio due to inadequate sensor sensitivity in current-generation receivers. This project will develop a strain gauge based borehole pressure transducer with 20 to 40 dB greater sensitivity than current-generation hydrophones based on mechanical amplification of strain. Phase I will evaluate several feasibility issues and culminate with design and borehole testing of a prototype strain gauge based sensor. Anticipated Results/Potential Commercial Applications as described by the awardee: In many areas such as West Texas, through-tubing crosswell operation could reduce well preparation cost by over 50% and reduce overall project cost to clients by 30 to 40%. Lower cost crosswell field operations and expanding the application of crosswell into major production fields such as the North Slope of Alaska, should fulfill the promise of crosswell seismic imaging in developing the interwell region.