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

Abstract

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.