State-of-the-art remote characterization of shallow marine sediments: the road to a fully integrated solution

摘要

Current methods for characterizing near-surface marine sediments rely on extensive coring/penetrometer testing and correlation to seismic facies. Little quantitative information is regularly derived from geophysical data beyond qualitative inferences of sediment characteristics based on seismic facies architecture. Even these fundamental seismostratigraphic interpretations can be difficult to correlate with lithostratigraphic data due to inaccuracies in the time-to-depth conversion of geophysical data and potential loss and/or compression of high-porosity and under-consolidated seafloor material during direct sampling. To complicate matters further, when quantitative information is derived from marine geophysical data, it often describes the sediments using terminology (e.g., acoustic impedance and seismic quality factor) that is impenetrable to geologists and engineers. In contrast, for hydrocarbon prospecting, reservoir characterization using quantitative inversion of geophysical data has developed enormously over the past 20 years or more. Impedance and amplitude- versus-angle inversion techniques are now commonplace, whereas computationally expensive waveform inversions are gaining traction, and there is a well-developed interface between these geophysical and reservoir engineering fields via rock physics.