An efficient elastic full-waveform inversion of multiple parameters with ocean-bottom seismometer data

Detailed knowledge of the subsurface elastic properties might provide much-needed insight into the subduction-zone structure and the estimation of reservoir parameters. Compressional and shear wave velocities can be inverted by elastic full-waveform inversion using multicomponent ocean-bottom seismometer data. However, this process is computationally intensive, requiring massive, repeated simulations scaling with the number of sources. Although source–receiver reciprocity can streamline elastic full-waveform inversion, it cannot be applied by directly interchanging the positions of sources and ocean-bottom seismometers. To reduce the computational cost, we develop a source–receiver reciprocal elastic full-waveform inversion, in which the reciprocity in multicomponent data can be accomplished by transforming the data matching from the original geometry to a specific form under the reciprocal geometry. This approach significantly reduces computational costs from twice the number of sources, as seen in conventional elastic full-waveform inversion, to a scale with the count of ocean-bottom seismometers. The tests on synthetic data verify that the proposed reciprocal elastic full-waveform inversion maintains accuracy while improving computational efficiency, and further application on the field data from East China Sea also showcases the efficiency of the proposed method, resulting in a speed-up of 10 times.