Patent ID: 6212952
Filing Date: 2001-04-10
Classification: E21B,G01V

Abstract:
A process for improving the measurement of a gravity gradient using an accelerometer type gradiometer having at least one pair of accelerometers that orbit an axis of rotation in a common plane, the accelerometers sensing changes in the gravity gradient as they move along their respective orbits and providing a corresponding electrical output therefrom, comprising:placing the gravity gradiometer at an observation point;tilting the common plane to a first angle below the local horizontal and aligning the axis to a first azimuth heading;taking data for a selected time period at the first azimuth heading;tilting the common plane to the first angle above the local horizontal;taking data for a selected time period at the first azimuth heading;re-aligning the axis to a second azimuth heading displaced from the first azimuth heading;taking data for a selected time period at the first angle above the local horizontal and at the second azimuth heading;tilting the common plane to the first angle below the local horizontal; andtaking data for a selected time period at the first angle below the local horizontal at the second azimuth heading.