| Popis: |
SUMMARY Multi-component acquisition systems today record incomplete data because they do not measure rotations. Geophones or accelerometers provide the linear motion, hydrophones provide the pressure, but no current commercial acquisition system includes sensors that measure rotations. Without rotations, the data provide incomplete recording of the wave field, because in three dimensions there are six degrees of freedom: three linear displacements and three rotations. We executed a small 2D seismic survey recording six components. We deployed three-component geophones and threecomponent rotation sensors measuring the pitch, roll, and yaw. We measured the pitch independently with closely-spaced geophones. Measuring rotations with closely spaced geophones is not practical in production, but we have used it in R&D to validate the rotation-sensor data. We compared the pitch measured by two independent methods and we found that they fit after instrument designature. We then demonstrate that the data provided by rotation sensors has additional value because it can be used in an SVD analysis to identify and separate ground roll and body waves. |
