Optical Technologies, Inc., (OpTech) proposes the development of a highly sensitive, inexpensive field-portable fiber-optic gravimeter capable of exceeding the sensitivity of current reference/observatory devices. OpTech has considerable experience in the research and development of a number of fiber-optic sensors for use in geophysical (e.g. Borehole deployment or underwater streamers), military, and industrial applications. The proposed gravimeter offers the following advantages: high sensitivity (-0.2 microgal); low cost; miniature sensing element (<65 cc phase ii)(cylinder 5.7 cm, diameter x 2.5cm high (exclusive of electronics)); light weight; emi/emp (surge) immunity; and total field capability (not in phases I or II). This device is capable of being operated in borehole, aerospace, land, and undersea environments, and will be an improvement over present gravimeters. The lattergenerally have very complex, delicate and expensive suspension systems which are required to develop sufficient displacement to achieve the required sensitivity. This imposes severe limitations on operational orientation. Furthermore, modern gravimeters suffer from temperature and pressure sensitivity and long settling time due to this suspension system. The inherent mechanical simplicity and balanced mechanical design of the proposed fiber-optic gravimeter is expected to overcome these problems while at the same time being capable of sub-microgal sensitivity.
