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Showing 1 to 20 of 42 for “"seamounts"”.
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Sound propagation around underwater seamounts
… of sound propagation around underwater seamounts. The depth-dependent sound velocity profile of typical ocean waveguides force sound to travel in convergence zones about a minimum sound speed depth. This ducted nature of the ocean makes modeling the acoustic field around seamounts …
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Sound propagation around underwater seamounts
… and communications. Underwater mountains, or seamounts, are ubiquitous throughout the world's oceans and can absorb and scatter acoustic energy, offering many interesting acoustic modeling challenges. The goal of the research performed in support of this thesis is to measure the acoustic …
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Sound propagation around underwater seamounts
… of sound propagation around underwater seamounts. The depth-dependent sound velocity profile of typical ocean waveguides force sound to travel in convergence zones about a minimum sound speed depth. This ducted nature of the ocean makes modeling the acoustic field around seamounts …
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Forward sound propagation around seamounts : application of acoustic models to the Kermit-Roosevelt and Elvis seamounts
… refraction, diffraction, and scattering by the seamounts. A towed hydrophone array, with 64 sensors cut for 250Hz (3m spacing), was used to measure the signals transmitted from the aforementioned broadband sources at many locations around the Kermit-Roosevelt and Elvis seamounts. Utilizing the …
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Forward sound propagation around seamounts : application of acoustic models to the Kermit-Roosevelt and Elivs seamounts
… refraction, diffraction, and scattering by the seamounts. A towed hydrophone array, with 64 sensors cut for 250Hz (3m spacing), was used to measure the signals transmitted from the aforementioned broadband sources at many locations around the Kermit-Roosevelt and Elvis seamounts. Utilizing the …
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A computer model for sound propagation around conical seamounts
This paper demonstrates a technique for computing the long-range sound pressure field around a penetrable conical seamount. The pressure field is generated by a harmonic point source. The seamount is positioned in a vertically stratified ocean. It is modeled as an outgrowth of the sediment layer …
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Faunal biogeography, community structure, and genetic connectivity of North Atlantic seamounts
… biogeography and biodiversity of deep-sea fauna. Seamounts are considered to play a defining role in faunal evolution, acting as regional centers of speciation, “stepping-stones” for dispersal, and/or refugia for deep-sea populations. The overarching goal of this dissertation was to examine the …
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Faunal biogeography, community structure, and genetic connectivity of North Atlantic seamounts
… biogeography and biodiversity of deep-sea fauna. Seamounts are considered to play a defining role in faunal evolution, acting as regional centers of speciation, "stepping-stones" for dispersal, and/or refugia for deep-sea populations. The overarching goal of this dissertation was to examine the …
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Sediment Deposition in the Deep Sea: from Seamounts to the Hadal Trenches
… scale topographical features were studied: seamounts in the North Atlantic and Pacific hadal trenches were observed via a radionuclide approach (234Th and 210Pb) in terms of assessing the control mechanism of carbon deposition to the seafloor. It is understood that topographical features …
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Mantle melting processes: evidences from ophiolites, large igneous provinces, and intraplate seamounts
… large igneous provinces, and intraplate seamounts to understand causes, timing and implications of melting in these different tectonic environments. We studied melting at extensional environments, in mid-ocean ridges and back-arc basins, preserved in ophiolites. The Santa Elena Ophiolite …
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Geochemical heterogeneity in the Hawaiian plume : constraints from Hawaiian volcanoes and Emperor seamounts
The 6000-km long, age-progressive linear Hawaii-Emperor Chain is one of the best defined hotspot tracks. This hotspot track plays an important role in the plume hypothesis. In this research, geochemical data on the Hawaiian-Emperor lavas are used to evaluate the plume hypothesis. There are …
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Patterns among micronekton communities in relation to environmental conditions at two shallow seamounts in the south-western Indian Ocean
Seamounts are ubiquitous topographic features across all ocean basins. They rise steeply through the water column from abyssal depths. Depending on their size, shape and summit depths, seamounts reportedly have an influence on the physical flow regimes which may promote the aggregation of …
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Basin-scale tidal measurements using acoustic tomography
… of phase-locked baroclinic tides generated by seamounts. Our estimates of barotropic M2 tidal dissipation by seamounts vary between 2 x 1016 and 1 X 1018 erg·s-1. The variation by two orders of magnitude is due to uncertainties in the numbers and sizes of seamounts. The larger dissipation (1 x …
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The Brazil current and intermediate Western Boundary Current flows through the Vitória-Trindade ridge
… Boundary Current (IWBC) through the submerged seamounts of the Vitória-Trindade Ridge (VTR), this work compiles data from three oceanographic commissions that took place in 2013 and 2014, between 19 e 23°S. One of the commissions was specially designed for the study of the flows in the main …
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Morphology and structure of the accretionary prism offshore North Sumatra, Indonesia and offshore Kodiak Island, USA : a comparison to seek a link between prism formation and hazard potential
… the subducting plate. Subduction of large-buried seamounts begins with creation of a proto-thrust zone seaward of the existing deformation front. As a seamount reaches the deformation front, steepening of the prism toe occurs by formation of out-of-sequence thrusts. Upon further subduction, a …
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Submesoscale coherent vortices in the deep Brazil Basin
… and destruction or detrainment events, near seamounts.
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Submesoscale coherent vortices in the deep Brazil Basin
… and destruction or detrainment events, near seamounts.
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SOFAR signal shaping : influence of topography and relative source depth
… blocking and partial blocking of direct rays by seamounts and narrow undersea ridges and (3) a sound speed profile displaced downwards by a filament of warm surface water. Comparisons with ray trace and normal mode models show that some of the received signals consist of a combination of slower, …
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The geological record of oceanic crustal accretion and tectonism at slow-spreading ridges
… detailed documentation of faults and volcanoes (seamounts) at the Mid-Atlantic Ridge from 25°25'N to 27°10'N and extending from zero-age crust at the ridge axis to -29 Ma crust on the ridge flank. This information was used to analyze the evolution of ocean crust from initial formation in the rift …
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