Method and apparatus for measuring seismic parameters of a seismic vibrator
View Patent ↗Apparatus and techniques for measuring seismic parameters, such as ground force, of a seismic vibrator used for generating seismic signals through a geological formation are provided. The seismic vibrator has a base plate positionable adjacent a ground surface of the geological formation. A sensor pad may be provided with an optical cable positionable between the base plate of the seismic vibrator and the ground surface of the geological formation, a laser for passing a light through the optical cable, and a detector for detecting disturbances in the laser light whereby a ground force applied to the ground surface may be determined.
1. A sensor pad for measuring seismic parameters of a seismic vibrator, the seismic vibrator for generating seismic waves through a geological formation, the seismic vibrator having a base plate positionable adjacent a ground surface of the geological formation, the sensor pad comprising:
an optical cable positionable between the base plate of the seismic vibrator and the ground surface of the geological formation;
a laser for passing a light through the optical cable; and
a detector for detecting disturbances in the light whereby a ground force of the seismic vibrator may be determined.
2. The sensor pad of claim 1 , wherein the optical cable is distributed over at least a portion of the base plate.
3. The sensor pad of claim 1 , further comprising a protective layer positionable about the optical cable.
4. The sensor pad of claim 3 , wherein the protective layer is selected from the group consisting of neoprene molded about the optical cable, a mat, a pad wafer, an adhesive layer, and combinations thereof.
5. The sensor pad of claim 1 , further comprising a securing agent between the cable and the base plate.
6. The sensor pad of claim 1 , wherein the optical cable is one of a single mode fiber optic cable, a multi-mode fiber optic cable, a microelectromechanical optical cable, a distributed optical cable and combinations thereof.
7. The sensor pad of claim 1 , further comprising at least one sensor.
8. The sensor pad of claim 1 , wherein the seismic parameter is one of a ground force, a stress, a strain, and combinations thereof.
9. A method for measuring seismic parameters, comprising:
positioning a seismic pad on a base plate of a seismic vibrator, the seismic pad comprising an optical cable, a laser, and a detector;
positioning the seismic pad of the base plate adjacent a ground surface of a geological formation;
generating seismic waves through the geological formation with the seismic vibrator;
passing a light from the laser through the optical cable; and
determining a ground force of the seismic vibrator by detecting disturbances in the light.
10. The method of claim 9 , further comprising providing a protective layer about the optical cable.