Stabilizing Two-term Clock-drift Inversion in Ocean Bottom Node Processing

In marine ocean bottom node (OBN) processing, removing the effects of water velocity variation and correcting for node positions and clock-drifts reduce statics in the data. Clock-drift for ocean-bottom nodes is usually modeled by two terms, a linear and a quadratic term. A global approach to invert for water velocity, node positions and clock-drift encounters further complication due to the two-term clock-drift. The unstable inversion of clock-drift compromises the quality of inversion for water velocity and node position. To avoid such instability, the authors
illustrate a strategy that helps to minimize the leakage from clock-drift inversion.