Gas-bubble inversion in marine sediments

Abstract

The acoustic properties of marine sediments can dramatically change because of the presence of gas-bubbles. Many applications require the detailed information of gas-bubbles, such as gas void fraction and gas-bubble size distribution. It is possible to relate the acoustic transmission measurements with bubble sizes. This study aims toward the development of an acoustic method able to both detect and quantify the gas present in marine sediments. This acoustic method adapts the effective density fluid model corrected by gas-bubble pulsations as a forward model and expands the unknown gas-bubble size distribution by a finite sum of cubit B-splines. The inverse problem can be transformed into solving the equation groups involving the coefficients of cubit B-splines. This method can be verified by testing analytical results and then applied to measurement sound speed and attenuation data which were acquired via transmission experiments.The acoustic properties of marine sediments can dramatically change because of the presence of gas-bubbles. Many applications require the detailed information of gas-bubbles, such as gas void fraction and gas-bubble size distribution. It is possible to relate the acoustic transmission measurements with bubble sizes. This study aims toward the development of an acoustic method able to both detect and quantify the gas present in marine sediments. This acoustic method adapts the effective density fluid model corrected by gas-bubble pulsations as a forward model and expands the unknown gas-bubble size distribution by a finite sum of cubit B-splines. The inverse problem can be transformed into solving the equation groups involving the coefficients of cubit B-splines. This method can be verified by testing analytical results and then applied to measurement sound speed and attenuation data which were acquired via transmission experiments.