scholarly journals Sound velocity in the deep sea: Examination of measurement data obtained from a deep submergence vehicle

1993 ◽  
Vol 94 (3) ◽  
pp. 1803-1803
Author(s):  
Toshio Tsuchiya ◽  
Yasutaka Amitani ◽  
Hiroshi Ochi ◽  
Toshiaki Kikuchi
Keyword(s):  
Sound Velocity ◽  
Deep Sea ◽  
Measurement Data

scholarly journals Spectral Relations of Hydro-Optical Characteristics in Coastal Waters of the South Coast of Crimea

2021 ◽  
Author(s):  
V. I. Mankovsky ◽  
E. V. Mankovskaya ◽  
◽  
Keyword(s):  
Attenuation Coefficient ◽  
Coastal Waters ◽  
Deep Sea ◽  
Secchi Depth ◽  
Measurement Data ◽  
South Coast ◽  
Optical Measurements ◽  
The South ◽  
Beam Attenuation ◽  
Beam Attenuation Coefficient

The article studies interrelations of the beam attenuation coefficient in different spectrum regions and spectral relations of beam attenuation coefficient to the Secchi depth in the coastal waters of the South Coast of Crimea. The data were used of in situ optical measurements obtained in 2008–2014 from a stationary oceanographic platform installed in the coastal waters of the South Coast of Crimea near the village of Katsiveli. According to the measurement data the relation was determined of the beam attenuation coefficient in eight parts of the spectrum in the wavelength range of 416–640 nm to the Secchi depth, which varies from 6 m to 17.5 m. Spectral distributions of the beam attenuation coefficient at different Secchi depths in coastal and deep sea waters were compared. As a result, it is concluded that the relationships between the spectral attenuation coefficient and the Secchi depth in coastal waters are not applicable to deep sea waters. It is shown that the feature of such equations in coastal waters is related to the higher concentration of fine suspended matter in them. Intercorrelation parameters were calculated of beam attenuation coefficients in different spectrum regions in coastal waters. High correlation coefficients make it possible to reconstruct distribution of the attenuation coefficient in a wide spectral range based on measurements at one wavelength in any spectrum region. The optimal spectral region to measure the beam attenuation coefficient is 468–527 nm.

Sound velocity in deep sea sediments

1968 ◽  
Vol 73 (4) ◽  
pp. 1259-1268 ◽  
Author(s):  
B. Charlotte Schreiber
Keyword(s):  
Sound Velocity ◽  
Deep Sea ◽  
Deep Sea Sediments

scholarly journals Sound Velocity Properties due to Salinity, Temperature and Depth of The Whole Banda Sea: A Marvelous Thing of The ~318 Meter Surface of Deep Sea

2018 ◽  
Vol 1 (1) ◽  
Keyword(s):  
Sound Velocity ◽  
Deep Sea ◽  
Sea Islands ◽  
North West ◽  
East Part ◽  
Influence Area ◽  
Different Depths ◽  
Sea Area ◽  
Interesting Area ◽  
West Monsoon

A marvelous thing of the ~300 meter surface of a deep sea in an interesting area like Banda sea surrounding by 11 small islands in Banda prefecture of Maluku province was investigated based on sound velocity properties due to salinity, temperature and depth of the whole Banda sea using INDESO data from 3rd March 2007 to 18th March 2014 or about 7 years plus 15 days (715.t) with the depth of the whole data reaching as deep as 318 meter from the Banda sea surface. From 9 different areas that we devided based on the whole Banda sea area, the east part of Banda sea was very attractive areas called as areas of no. 3, no. 6 and no. 9 due to their economic potential exploration, respectively. According to our ongoing works during the 715.t, we discovered that the speed velocity of sound propagating (vs) in the sea was mainly temperature dependent in 3 different depths called as (1) Mixed layer (ML), (2) Thermocline layer (TL), and (3) Below Thermocline layer (BTL) on top 318 m surface of the deep Banda sea. The detail of the influences of North West Monsoon (NWM) and South East Monsoon (SEM) related to the vs is discussed. Our results suggest that the east part of the whole Banda sea produced faster vs than that in the others 6 areas. While when the NWM, there was a shift of the vs especially in TL from the east to the center of Banda sea that made Seram and Buru sea islands warm. In addition, in the influence area due to NWM of BTL, the vs is faster in the south area of Banda sea.

A RESONANT CHAMBER METHOD FOR SOUND VELOCITY AND ATTENUATION MEASUREMENTS IN SEDIMENTS

Geophysics ◽  
1956 ◽  
Vol 21 (2) ◽  
pp. 305-319 ◽  
Author(s):  
George Shumway
Keyword(s):  
Shallow Water ◽  
Sound Velocity ◽  
Deep Sea ◽  
Atmospheric Pressure ◽  
San Diego ◽  
Sea Water ◽  
Resonance Method ◽  
Water Velocity ◽  
Red Clay ◽  
Shallow Water Sediments

Sound velocity and attenuation measurements in unconsolidated marine sediments have been made by a resonance method which utilizes a thin‐walled plastic cylinder as a pressure‐release container to hold samples. Velocities were determined from resonant frequencies which lay between 23 and 36 kc/sec for the 2 inch diameter by 4 inch long cylindrical container used. Attenuation was determined from the sharpness of the resonant modes. Relatively undisturbed sediment samples were obtained by diver, in shallow water, using the same plastic containers in which the acoustic measurements are made. Deep sea samples were obtained by cutting sections from cores which were taken in plastic tubes. Velocities for shallow water sediments in the San Diego area ranged from 4,840 ft/sec (0.978 times sea water velocity) for fine silt to 5,680 ft/sec (1.147 times sea water velocity) for medium sand, measured at 60°F. and atmospheric pressure. Velocities in deep‐sea red clay samples ranged between 0.980 and 1.040 times the sea water velocity, at 60°F. and atmospheric pressure. Attenuation coefficients for shallow‐water San Diego sediments varied from about 1 to 4 db/ft for silts, to about 3 to 8 db/ft for sand.

scholarly journals Development of a Position Measuring Device of a Deep-Sea Pipeline Based on Flange Center Positioning

2020 ◽  
Vol 8 (2) ◽  
pp. 86
Author(s):  
Zhuo Wang ◽  
Hong-xing Dang ◽  
Tao Wang ◽  
Bo Zhang
Keyword(s):  
Transmission Coefficient ◽  
Deep Sea ◽  
Measurement Data ◽  
Outer Wall ◽  
Large Error ◽  
Measuring Device ◽  
Outer Circle ◽  
Measuring Devices ◽  
Oil Pipelines ◽  
Positioning Method

A deep-sea pipeline position and attitude-measuring device based on pipeline outer circle positioning can measure the spatial relative positions of the end faces of two oil pipelines in the deep sea. This device can provide the necessary data to make a transition pipeline connecting two sections of oil pipelines together. However, after analyzing the data measured by this device, it is found that the measurement data has a large error because the error transmission coefficient of the measurement value is too large. In order to reduce the error transfer coefficient, a new measuring device for measuring the posture of deep-sea pipelines by a tensioning rope was proposed. Unlike previous measuring devices, this measuring device is based on the positioning of the flange center of the pipe instead of the pin on the outer circle of the pipe. With the comparison of positioning methods between fixing in the center of flange and fixing the outer wall of pipeline, the former can reduce the transition matrix in the process of solving the relative position of the two pipes, and then reduce the magnification of the measurement sensor error. It also reduces two measurement parameters. The solving formula of the position and attitude of the measuring device based on the outer circle positioning of the pipeline is analyzed. It is proved that the error transmission coefficient of the measuring device based on the flange center positioning is smaller. Experiments show that compared with the positioning method based on the outer circle of the pipe, the positioning method based on the flange center has a higher accuracy.

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