Validation and Testing of SALSA3D: A global model of compressional wave speed for the crust and mantle

A recently introduced theoretical model of wave propagation in an unconsolidated, sandy marine sediment is discussed in this article. Essentially, the model consists of four analytical expressions, which specify four wave properties of the sediment, namely the speed and attenuation of the compressional and the shear wave. These expressions contain just three unknown constants, which must be evaluated from data. A technique is described in which these constants are determined from measured values of the compressional wave speed, the shear wave speed, and the shear wave attenuation. This technique is applied to preliminary data from O.N.R.s SAX'99 recent experiment on a sandy sediment in the Gulf of Mexico. From the fully specified equations, the fourth wave property, the attenuation of the compressional wave, is computed and found to lie within 0.5 dB/m of the measured value. Based on this limited evidence, it appears that the wave properties of an unconsolidated sediment are highly correlated and predictable. According to the theory, the causal connections between the wave properties originate in the sliding of one micro/asperity against another on the surfaces of contact between contiguous grains in the medium.

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Compressional Wave Speed Dispersion and Attenuation in Carbonate Sediments, Kaneohe Bay, Oahu, HI

IEEE Journal of Oceanic Engineering ◽

10.1109/joe.2008.920212 ◽

2008 ◽

Vol 33 (4) ◽

pp. 367-374 ◽

Cited By ~ 3

Author(s):

Eva-Marie Nosal ◽

Chunhui Tao ◽

Stefano Baffi ◽

Shunsheng S. Fu ◽

Michael D. Richardson ◽

...

Keyword(s):

Wave Speed ◽

Compressional Wave ◽

Carbonate Sediments ◽

Kaneohe Bay ◽

Dispersion And Attenuation

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Simultaneous Reconstruction of Compressional Wave Speed and Density Profiles from Modal Eigenvalues

Journal of Computational Acoustics ◽

10.1142/s0218396x98000181 ◽

1998 ◽

Vol 06 (01n02) ◽

pp. 257-267 ◽

Cited By ~ 4

Author(s):

Subramaniam D. Rajan

Keyword(s):

Continuous Function ◽

Shallow Water ◽

Density Profile ◽

Wave Speed ◽

Synthetic Data ◽

Compressional Wave ◽

Simple Approach ◽

Density Profiles ◽

Processing Scheme ◽

Simultaneous Reconstruction

In this paper we present a simple approach for estimating the compressional wave speed and density profiles of sediments in a shallow water environments from modal eigenvalues. Methods published earlier in the literature called for data at two frequencies and had to make the assumption that the density profile is a continuous function. Further, the processing scheme was difficult to implement. The method presented here requires data from only one frequency and allows for discontinuities in the density profile. The performance of the proposed method is studied using synthetic data.

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Inversion for Range-Dependent Sediment Compressional-Wave-Speed Profiles From Modal Dispersion Data

IEEE Journal of Oceanic Engineering ◽

10.1109/joe.2009.2039377 ◽

2010 ◽

Vol 35 (1) ◽

pp. 43-58 ◽

Cited By ~ 17

Author(s):

Subramaniam D. Rajan ◽

Kyle M. Becker

Keyword(s):

Wave Speed ◽

Compressional Wave ◽

Modal Dispersion ◽

Dispersion Data

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Estimation of Compressional Wave Speed in Marine Sediments using Biot Stoll Model and Buckinghams Grain shearing Model

Defence Science Journal ◽

10.14429/dsj.70.14365 ◽

2020 ◽

Vol 70 (3) ◽

pp. 336-341

Author(s):

A.P. Anu ◽

P. Velayudhan Nair ◽

C.P. Uthaman ◽

T. Pradeep Kumar

Keyword(s):

Wave Speed ◽

Theoretical Models ◽

Compressional Wave ◽

Acoustic Properties ◽

Coefficient Of Determination ◽

Elastic Model ◽

Experimental Assessment ◽

Empirical Relations ◽

Indian Waters ◽

Seafloor Sediments

Acoustic properties of seafloor sediments can be estimated using theoretical models by giving geophysical properties of sediments as inputs to the respective models. Empirical relations connecting the geophysical and geoacoustic properties are available in literature. In this study an experimental assessment of two such theoretical models viz., Biot-Stoll model (BSM), a poro-elastic model and the Buckingham’s grain shearing (GS) model, a visco-elastic model is done by estimating the compressional wave speed. Compressional wave speed is measured using in-house developed sediment velocimeter and is compared with the speed estimated using both the models and a regression analysis was done. It was observed that the Coefficient of determination R2 for BSM and GS model are 0.769 and 0.729, respectively. It shows that once the constants used in GS model are evaluated for the Indian waters, then it can be used to estimate the acoustic properties of sediments.

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