Patent ID: 6353577
Filing Date: 2002-03-05
Classification: G01V

Abstract:
A seismic sensor unit, particularly but not exclusively adapted for land applications, comprising:a case that houses, at least one electric seismic sensor element adapted for generating a sensor unit output signal, said seismic sensor element being a feedback controlled accelerometer adapted for generating a gravity related sensor unit output signal, said accelerometer having a component with an associated axis, and at least one magnetometer, the magnetometer being a flux gate magnetometer including an associated electronic module adapted for generating one or more magnetometer output signals in the form of an AC flux across the magnetometer sensors, said magnetometer having a component with an associated axis, the axis of the accelerometer component being approximately parallel to the axis of the magnetometer component, said magnetometer output signals generated from said magnetometer and said gravity related sensor unit output signal generated from said feedback controlled accelerometer together in combination determining and compensating for an orientation of the seismic sensor unit in view of inclination and azimuth, a first electronic circuit being responsive to the gravity related sensor unit output signals and the magnetometer output signals adapted for digitizing said sensor unit output signals that are generated from said seismic sensor element and the magnetometer output signals that are generated from the magnetometer, and a second electronic circuit, said second electronic circuit including a telemetry interface module adapted for exchanging signals and data with a seismic data acquisition network, a signal filter module, and a logic and signal conditioning module; and a cable, fixed to the case, for allowing a supply of power to the sensor unit and for transmitting the sensor unit output signal to other seismic sensor units or to a signal processing unit.