The acoustic properties of seafloor sediments on continental slopes play a crucial role in underwater propagation, communication, and detection. To investigate the characteristics spatial distribution patterns slope, geoacoustic experiment was conducted northwestern South China Sea. covered two sections: one crossing shelf slope downslope direction, other near break along-slope direction. In situ techniques, sediment sampling, laboratory measurements were used to acquire data (such as sound...

Seafloor sediment acoustics is a burgeoning field of marine scientific research. In situ measurement technique key for investigating acoustic properties. Establishing correlation between in parameters and physical great significance advancing the theory seafloor acoustics. This study employed an system to measure sound speed attenuation various types sediment, such as sand, silty clay, clayey silt. The results showed that were strongly curvilinear correlated with properties, wet bulk...

The mechanical structure, the function modules, working principles, and a sea trial of newly developed ballast in situ sediment acoustic measurement system are reported this study. relies on its own weight to insert transducers into seafloor sediments can accurately measure penetration depth using specially designed mechanism. comprises an underwater position monitoring status judgment module has two operation modes: self-contained real-time visualization. maximum water is 3,000 m, measured...

To accurately characterize sound speed dispersion of shallow sediments in the Southern Yellow Sea, three types sediments, i.e., silt, clayey and silty clay, were selected to measure speeds at 25–250 kHz. Over frequency range, vary approximately from 1,536 1,565 m s−1 silt sediment, 1,511 1,527 1,456 1,466 clay sediment. The exhibits a slow increase with nearly linear gradient, but these have different characteristics. sediment relatively coarse grains has most significant dispersion, while...

Abstract The object of this study was to obtain the acoustic properties fine sandy sediments with approximately 22% clay content from East China Sea Shelf. This conducted in situ measurement measure sound speed and attenuation, eight sediment cores were collected measured wet bulk density, porosity, mean grain size laboratory environment. correlations between ratio physical show good accordance two empirical equations, while attenuation factor deviated regression curves. Both data obvious...

Based on the acoustic and physical data of typical seafloor sediment samples collected in East China Sea, this study super parameter selection contribution characteristic factors machine learning model for predicting sound speed sediments was conducted using eXtreme gradient boosting (XGBoost) algorithm. An XGBoost established based five parameters: density (ρ), water content (w), void ratio (e), sand (S), average grain size (Mz). The results demonstrated that had highest accuracy when...

Three types of sediments were selected to measure their sound speed under changing temperature and pressure conditions in laboratory. The effects on trends analyzed. results showed that, with increasing pressure, the exhibits an trend all sediments. For each sample, ratio that seawater almost remained unchanged at different pressures temperatures, a maximum fluctuation 1.09% for dependence 0.68% dependence. Combining analysis experimental correction procedure given by Hamilton, specific...

Based on the data of acoustic and physical properties seafloor sediments obtained continental shelf area East China Sea (ECS), prediction equations sediment sound speed based single dual parameters were established, correlation with was discussed. The results show that (c) is strongly correlated water content (w), density (ρ), void ratio (e), mean grain size (Mz) median (Md), coefficient determination R2 empirical regression equation generally greater than 0.80, while compression (a) modulus...

We present new Sm–Nd isotope data for sediments from a core located on the continental slope of St. Pierre Bank Canada’s east coast. The Nd analyses indicate that were derived two principal sources: North American Shield yields an average early Proterozoic isotopic signature and younger attributed to Appalachian crustal sources. Appalachian-sourced predominated during last glacial maximum (LGM) associated with low sedimentation rates (<30 cm/ka), exception strong in detrital carbonate...

The acoustic characteristics of three fine-grained sediments (silty sand, silt, silty clay) in the South China Sea (SCS) were measured and analyzed at high frequency range 27–247 kHz. measurement results show that sound speed dispersion is a positive linear relation range, attenuation follows nonlinear dependence, α = kfn, where n ranges from 0.59 to 0.85 for different SCS. dependence compared with published literature. It was found clay, clayey these four are basically consistent; general,...

How to improve the prediction accuracy of compressional wave speed has always been one basic research subjects in geoacoustics study field. Due stability granularity, whether laboratory or seabed environment, regression relationship between and granularity is an important sound inversion method. Machine Learning (ML) provides a new solution for more efficient systems. In this study, two ML algorithm, Random forest (RF) Support Vector Regression (SVR), combined with nine parameters (mean...

Based on data the shear wave speed and physical properties of shallow sediment samples collected in northwest South China Sea, hyperparameter selection contribution characteristic factors machine learning model for predicting seafloor sediments were studied using eXtreme Gradient Boosting (XGBoost) algorithm. An XGBoost was established based four parameters sediments: porosity ( n ), water content w density ρ average grain size M Z ). The result reveals that: (1) has a good correlation with...

The high-frequency acoustic properties of seafloor sediments are very significant in study and underwater field. In order to measure the sound speed attenuation for small-scale sediment cores more accurately, this developed a water coupled laboratory measurement system based on Richardson-Briggs technique. This method used correlation comparison waveforms received core identical reference tubes filled with attenuation. clayey silt sample were measured using system. frequency dependence...

Numerous factors influence the acoustic characteristics of seafloor sediments, necessitating a comprehensive study that combines theoretical analysis, laboratory measurements and in situ to support prediction inversion. In this study, porosity-based effective density fluid model (P-EDFM) is established analyze variation properties with porosity sediments. On biases P-EDFM, attribute measured sound velocity attenuation coefficient sediment Series 9B SAX99 was well interpreted within frequency...

Based on the data of sound speed and physical–mechanical properties 300 seafloor sediment samples collected in middle area Southern Yellow Sea, a backpropagation (BP) neural network algorithm is used herein to study topology corresponding neuron characteristic factors. A model for predicting based density, water content, porosity, void ratio, liquid limit, plastic clay content Sea established. The results show that prediction accuracy highest when contains seven input layer neurons, ten...