Patent ID: 6789424
Filing Date: 2004-09-14
Classification: G01P,G01V

Abstract:
An apparatus for vertical seismic profiling of the earth having an x-direction, a y-direction and a z-direction orthogonal to each other, said apparatus comprising:an optical fiber transmission cable; and a plurality of accelerometers coupled to the earth and in optical communication with the optical fiber transmission cable and positioned in each of the three orthogonal directions, each accelerometer measuring an acceleration in a predetermined direction corresponding to one of the orthogonal directions, each of the accelerometers comprising: a rigid housing; a mass; and at least two coiled elastic support members comprised of optical fiber, wherein the coiled support members are attached to opposite ends of said housing and further attached to said mass, said elastic support members suspending said mass within said housing, wherein at least a portion of one of said elastic support members comprises a transducer capable of measuring a change in length of at least a portion of the one elastic support member in response to an acceleration along said predetermined direction and capable of providing a respective sensing light signal indicative of the change in length.