Advances in 6-C seismology: applications of combined translational and rotational motion measurements in global and exploration seismology

Over the past decade, the potential of collocated measurements of six-component (6C) data (3C of translational and 3C of rotational motion) has been demonstrated in global seismology using high-sensitivity, observatory-based ring laser technology. Proposed applications of 6C seismology range from tomographic reconstruction of near-receiver structure to the reduction of non-uniqueness in seismic source inverse problems. Applications to exploration problems have so far been hampered by the lack of appropriate sensors but a number of applications have been proposed and demonstrated with array-derived rotational motion estimates. With the recent availability of, for example, fibre-optic based high-sensitivity rotational motion sensors, widespread applications of 6C techniques to exploration problems are in sight. Potential applications are based on, for example, the fact that the extended set of combined translational and rotational motion observations enables carrying out array-type processing with single-st...