Type
ArticleKAUST Department
Ali I. Al-Naimi Petroleum Engineering Research Center (ANPERC)Physical Science and Engineering (PSE) Division
Energy Resources and Petroleum Engineering Program
Date
2020-10-24Online Publication Date
2020-10-24Print Publication Date
2021-01Submitted Date
2019-06-19Permanent link to this record
http://hdl.handle.net/10754/665747
Metadata
Show full item recordAbstract
Offshore geoengineering requires reliable sediment parameters for analysis and design. This study proposes a robust framework for effective stress-dependent geotechnical and geoacoustic properties for seabed analysis based on geophysical models, new experimental data, and extensive data sets compiled from published studies that cover a wide range of marine sediments and depths. First, effective stress-dependent porosity versus depth profiles are computed using compaction models that are valid for a wide stress range. Then, P- and S-wave velocity data are analyzed in the context of effective stress-controlled density, shear stiffness, and bulk modulus within a Hertzian-Biot-Gassmann framework. Finally, this study selects six distinct “reference sediments” that range from clean sands to highplasticity clays and assigns self-consistent compaction and shear stiffness properties using well-known correlations reported in the literature in terms of specific surface, plasticity, and grain characteristics. Results show that robust physical models for compaction and stiffness adequately predict depth-dependent geotechnical and geoacoustic properties according to sediment type. The asymptotic void ratio at low effective stress eL determines the sediment density ρo at the sediment–water boundary. New experimental studies show that the characteristic asymptotic sediment density ρo at very low effective stress σ 0z → 0 controls the high-frequency acoustic reflection used for bathymetric imaging. The proposed analysis of geoacoustic data can be used to obtain first-order estimates of seafloor sediment properties and to produce sediment-type seafloor maps. DCitation
Lyu, C., Park, J., & Carlos Santamarina, J. (2021). Depth-Dependent Seabed Properties: Geoacoustic Assessment. Journal of Geotechnical and Geoenvironmental Engineering, 147(1), 04020151. doi:10.1061/(asce)gt.1943-5606.0002426Sponsors
Support for this research was provided by the KAUST Endowment at King Abdullah University of Science and Technology. Gabrielle E. Abelskamp edited the manuscript.Additional Links
http://ascelibrary.org/doi/10.1061/%28ASCE%29GT.1943-5606.0002426ae974a485f413a2113503eed53cd6c53
10.1061/(asce)gt.1943-5606.0002426
Scopus Count
Except where otherwise noted, this item's license is described as This work is made available under the terms of the Creative Commons Attribution 4.0 International license.