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On The Effect Of Random Errors In Gridded Bathymetric Compilations, Martin Jakobsson, Brian R. Calder, Larry A. Mayer
On The Effect Of Random Errors In Gridded Bathymetric Compilations, Martin Jakobsson, Brian R. Calder, Larry A. Mayer
Center for Coastal and Ocean Mapping
We address the problem of compiling bathymetric data sets with heterogeneous coverage and a range of data measurement accuracies. To generate a regularly spaced grid, we are obliged to interpolate sparse data; our objective here is to augment this product with an estimate of confidence in the interpolated bathymetry based on our knowledge of the component of random error in the bathymetric source data. Using a direct simulation Monte Carlo method, we utilize data from the International Bathymetric Chart of the Arctic Ocean database to develop a suitable methodology for assessment of the standard deviations of depths in the interpolated …
Automatic Estimation Of The Seafloor Geomorphology Of The Santos Basin, Brazil, Brian R. Calder, Luciano E. Fonseca, Joao B. Francolin
Automatic Estimation Of The Seafloor Geomorphology Of The Santos Basin, Brazil, Brian R. Calder, Luciano E. Fonseca, Joao B. Francolin
Center for Coastal and Ocean Mapping
The bathymetry and acoustic backscatter of Santos Basin, Brazil were mapped using a SeaBeam 2112 (12 kHz, 151 beam) Multibeam Echosounder (MBES) aboard the R/V Falcon Explorer. This MBES data was acquired from January-November, 2000, during a high-resolution multi-channel 3D seismic survey, resulting in 380 parallel lines of 90 km length, spaced 250 m apart. The final survey mapped an area of 5,000 km${}^2$ in water depths of 900--2000 m. These closely spaced multibeam tracks resulted in an average overlap between swaths of 1000%, thereby ensonifying most areas of the seafloor at least ten times. Traditional (hand) processing of a …
Multi-Scale Visualization Of Remote Sensing And Topographic Data Of The Amazon Rain Forest, Luciano E. Fonseca, F P. Miranda, C Beisl, J Souza-Fonseca
Multi-Scale Visualization Of Remote Sensing And Topographic Data Of The Amazon Rain Forest, Luciano E. Fonseca, F P. Miranda, C Beisl, J Souza-Fonseca
Center for Coastal and Ocean Mapping
PETROBRAS (the Brazilian national oil company) built a pipeline to transport crude oil from the Urucu River region to a terminal in the vicinities of Coari, a city located in the right margin of the Solimoes River. The oil is then shipped by tankers to another terminal in Manaus, capital city of the Amazonas state. At the city of Coari, changes in water level between dry and wet seasons reach up to 14 meters. This strong seasonal character of the Amazonian climate gives rise to four distinct scenarios in the annual hydrological cycle: low water, high water, receding water, and …
Arctic Ocean Physiography, Martin Jakobsson, Arthur Grantz, Yngue Kristoffersen, Ron Macnab
Arctic Ocean Physiography, Martin Jakobsson, Arthur Grantz, Yngue Kristoffersen, Ron Macnab
Center for Coastal and Ocean Mapping
The first order physiographic provinces of the Arctic Ocean has been defined using the recently updated International Bathymetric Chart of the Arctic Ocean (IBCAO) grid model as the main database and a semi-quantitative approach. The first step in our classification of physiographic provinces is an evaluation of seafloor gradients contained in a slope model that was derived from the IBCAO grid. The slope information reveals certain seafloor process-related features, which add to the bathymetric information. Using interactive 3D-visualization, the slope and bathymetric information were simultaneously analyzed and certain slope intervals of the Arctic Ocean seafloor were found to generally characterize …
Seafloor Characterization From Spatial Variation Of Multibeam Backscatter Vs."Best Estimated" Grazing Angle, Tianhang Hou, Larry A. Mayer, Christian De Moustier, Barbara J. Kraft
Seafloor Characterization From Spatial Variation Of Multibeam Backscatter Vs."Best Estimated" Grazing Angle, Tianhang Hou, Larry A. Mayer, Christian De Moustier, Barbara J. Kraft
Center for Coastal and Ocean Mapping
Backscatter vs. grazing angle, which can be extracted from multibeam backscatter data, depends on characteristics of the multibeam system and the angular responses of backscatter that are characteristic of different seafloor properties, such as sediment hardness and roughness. Changes in backscatter vs. grazing angle that are contributed by the multibeam system normally remain fixed over both space and time. Therefore, they can readily be determined and removed from backscatter data. The component of backscatter vs. grazing angle due to the properties of sediments varies from location to location, as the sediment changes. The sediment component of variability can be inferred …
An Integrated Bathymetric And Topographic Digital Terrain Model Of The Canadian Arctic Archipelago, Goran Alm, Ron Macnab, Martin Jakobsson, Johan Kleman, Mark Mccracken
An Integrated Bathymetric And Topographic Digital Terrain Model Of The Canadian Arctic Archipelago, Goran Alm, Ron Macnab, Martin Jakobsson, Johan Kleman, Mark Mccracken
Center for Coastal and Ocean Mapping
No abstract provided.
Lake Tahoe Bottom Characteristics Extracted From Shoals Lidar Waveform Data And Compared To Backscatter Data From A Multibeam Echo Sounder, G. Elston, James V. Gardner
Lake Tahoe Bottom Characteristics Extracted From Shoals Lidar Waveform Data And Compared To Backscatter Data From A Multibeam Echo Sounder, G. Elston, James V. Gardner
Center for Coastal and Ocean Mapping
The waveforms recorded by airborne lidar bathymetry (ALB) systems are currently processed only for depth information. In addition to bathymetry, multibeam echo sounder (MBES) systems provide backscatter data in which regions of different acoustic properties are distinguishable. These regions can often be correlated to different bottom types. Initial attempts to extract equivalent data from the ALB waveforms have confirmed the expectation that such information is encoded in those waveforms. Water clarity, bathymetry, and bottom type control the detailed shapes of ALB waveforms in different ways. Specific features of a bottom-reflected signal can be identified, for example its rise-time and amplitude, …
Resolving The Ripples (And A Mine): High-Resolution Multibeam Survey Of Martha's Vineyard Onr Mine Burial Program Field Area, Larry A. Mayer, Richard Raymond, Gerd Glang, Lloyd C. Huff
Resolving The Ripples (And A Mine): High-Resolution Multibeam Survey Of Martha's Vineyard Onr Mine Burial Program Field Area, Larry A. Mayer, Richard Raymond, Gerd Glang, Lloyd C. Huff
Center for Coastal and Ocean Mapping
In an effort to better understand the coastal processes responsible for the burial and exposure of small objects on the seafloor, the Office of Naval Research is sponsoring the Mine Burial Program. Among the field areas chosen for this program is the site of the Martha's Vineyard Coastal Observatory (MVCO), a permanent instrumented node in 12 m of water about 500 m off the southern shore of Martha?s Vineyard. In support of the ONR program, several site surveys of the MVCO area have been conducted (see Goff et al); here we report the result of the most recent of these …
Near Bottom Sediment Characterization Offshore Sw San Clemente Island, Daniel D. Sternlicht, Christian De Moustier
Near Bottom Sediment Characterization Offshore Sw San Clemente Island, Daniel D. Sternlicht, Christian De Moustier
Center for Coastal and Ocean Mapping
Normal incidence, 23.5 kHz seafloor acoustic backscatter data and bottom video were measured with the Deep Tow instrument package of the Scripps Institution of Oceanography in 100 meter water depth south of San Clemente Island, CA. The collected data were processed using an echo envelopesediment characterization method, to derive geoacoustic parameters such as particle mean grain size and the strength of the power law characterizing the roughness energy density spectrum of thesediment-water interface. Two regions, sand and silt, were selected based on available ground truth, perceived along-track sediment homogeneity, data quality and tow fish stability. Distinction between sand and fine …
A Prototype 1:6 Million Map, Martin Jakobsson
A Prototype 1:6 Million Map, Martin Jakobsson
Center for Coastal and Ocean Mapping
No abstract provided.
3-D Visualization Of Ibcao, Martin Jakobsson, Ron Macnab
3-D Visualization Of Ibcao, Martin Jakobsson, Ron Macnab
Center for Coastal and Ocean Mapping
No abstract provided.
Sensor-Assisted Video Mapping Of The Seafloor, Yuri Rzhanov, Lloyd C. Huff, Randy G. Cutter Jr., Larry A. Mayer
Sensor-Assisted Video Mapping Of The Seafloor, Yuri Rzhanov, Lloyd C. Huff, Randy G. Cutter Jr., Larry A. Mayer
Center for Coastal and Ocean Mapping
In recent years video surveys have become an increasingly important ground-truthing of acousticseafloor characterization and benthic habitat mapping studies. However, the ground-truthing and detailed characterization provided by video are still typically done using sparse sample imagery supplemented by physical samples. Combining single video frames in a seamless mosaic can provide a tool by which imagery has significant areal coverage, while at the same time showing small fauna and biological features at mm resolution. The generation of such a mosaic is a challenging task due to height variations of the imaged terrain and decimeter scale knowledge of camera position. This paper …
Seafloor Video Mapping: Modeling, Algorithms, Apparatus, Yuri Rzhanov, Lloyd C. Huff, Randy G. Cutter Jr.
Seafloor Video Mapping: Modeling, Algorithms, Apparatus, Yuri Rzhanov, Lloyd C. Huff, Randy G. Cutter Jr.
Center for Coastal and Ocean Mapping
This paper discusses a technique used for construction of high-resolution image mosaic from a videosequence and the synchronously logged camera attitude information. It allows one to infer geometric characteristics of the imaged terrain and hence improve the mosaic quality and reduce the computational burden. The technique is demonstrated using numerical modeling and is applied to videodata collected on Rainsford Island, Mass. Calculation of the transformation relating consecutive image frames is an essential operation affecting reliability of the whole mosaicing process. Improvements to the algorithm are suggested, which significantly decrease the possibility of convergence to an inappropriate solution.
Underwater Video Survey: Planning And Data Processing, Yuri Rzhanov, Lloyd C. Huff, Randy G. Cutter Jr.
Underwater Video Survey: Planning And Data Processing, Yuri Rzhanov, Lloyd C. Huff, Randy G. Cutter Jr.
Center for Coastal and Ocean Mapping
The importance of underwater video surveys as an exploration tool has been steadily increasing over recent years [1]. Better photographic equipment, more effective sources of illumination, and improved processing techniques - all make video surveying a reliable tool for seafloor habitat mapping, sediment boundary delineation and groundtruthing, mapping and documentation of forensic and archaeological sites. There is a change in attitude towards video surveying that affects the way the data is collected, and hence its quality. Earlier video data processing algorithms had to cope with whatever was recorded (often simultaneously with acquisition of other data, considered to be more important). …
The Navigation Surface: A New Database Approach To Creating Multiple Products From High-Density Surveys, Shep M. Smith Lt, Lee Alexander, Andy Armstrong
The Navigation Surface: A New Database Approach To Creating Multiple Products From High-Density Surveys, Shep M. Smith Lt, Lee Alexander, Andy Armstrong
Center for Coastal and Ocean Mapping
High-resolution bathymetric surveys are revolutionising hydrographic surveying. ln addition to safety-of-navigation , there are a host of other uses for high-resolution bathymetry, including habitat mapping, hydrologic modelling, marine archaeology, and marine environmental protection. However, at present, there is no suitable method that can be used to produce multiple products that meet the needs of both navigation customers and other users . A research project conducted at the University of New Hampshire developed a model of the seafloor that is optimised for safety-of-navigation . This new technique bypasses the rather subjective, 'selected soundings' approach. Instead, a statistical model is created directly …
The High-Frequency Backscattering Angular Response Of Gassy Sediments: Model/Data Comparison From The Eel River Margin, California, Luciano E. Fonseca, Larry A. Mayer, Dan Orange, Neal Driscoll
The High-Frequency Backscattering Angular Response Of Gassy Sediments: Model/Data Comparison From The Eel River Margin, California, Luciano E. Fonseca, Larry A. Mayer, Dan Orange, Neal Driscoll
Center for Coastal and Ocean Mapping
A model for the high-frequency backscatter angular response of gassy sediments is proposed. For the interface backscatter contribution we adopted the model developed by Jackson et al. @J. Acoust. Soc. Am. 79, 1410–1422 ~1986!#, but added modifications to accommodate gas bubbles. The model parameters that are affected by gas content are the density ratio, the sound speed ratio, and the loss parameter. For the volume backscatter contribution we developed a model based on the presence and distribution of gas in the sediment. We treat the bubbles as individual discrete scatterers that sum to the total bubble contribution. This total bubble …
The Compilation And Analysis Of Data Relevant To A U.S. Claim Under United Nations Law Of The Sea Article 76: A Preliminary Report, Larry A. Mayer, Martin Jakobsson, Andy Armstrong
The Compilation And Analysis Of Data Relevant To A U.S. Claim Under United Nations Law Of The Sea Article 76: A Preliminary Report, Larry A. Mayer, Martin Jakobsson, Andy Armstrong
Center for Coastal and Ocean Mapping
No abstract provided.
Hypsometry And Volume Of The Arctic Ocean And Its Constituent Seas, Martin Jakobsson
Hypsometry And Volume Of The Arctic Ocean And Its Constituent Seas, Martin Jakobsson
Center for Coastal and Ocean Mapping
This paper presents an analysis of the Arctic Ocean and its constituent seas for seafloor area distribution versus depth and ocean volume. The bathymetry from the International Bathymetric Chart of the Arctic Ocean (IBCAO) is used together with limits defining this ocean and its constituent seas from the International Hydrographic Organization (IHO) as well as redefined limits constructed to confine the seas to the shallow shelves. IBCAO is a bathymetric grid model with a resolution of 2.5 x 2.5 km, which significantly improved the portrayal of the Arctic Ocean seafloor through incorporation of newly released bathymetric data including echo soundings …
Geometric And Radiometric Correction Of Multibeam Backscatter Derived From Reson 8101 Systems, Jonathan Beaudoin, J.E. Hughes Clarke, Edward J. Van Den Ameele, James V. Gardner
Geometric And Radiometric Correction Of Multibeam Backscatter Derived From Reson 8101 Systems, Jonathan Beaudoin, J.E. Hughes Clarke, Edward J. Van Den Ameele, James V. Gardner
Center for Coastal and Ocean Mapping
A common by-product of multibeam surveys is a measure of the backscattered acoustic intensity from the seafloor. These data are of immense interest to geologists and geoscientists since maps of the acoustic backscatter strength can be used to infer physical properties of the sea bottom, such as impedance, roughness and volume inhomogeneity. Before such maps can be created from multibeam acoustic backscatter data, however, two tasks must be performed.
1. The data must be geographically registered using the bathymetric profile collected by the multibeam (which accounts for full orientation and refraction), as opposed to using the traditional flat-seafloor assumption. This …
Haptic Interface For Center Of Workspace Interaction, Rick Komerska, Colin Ware, Matt D. Plumlee
Haptic Interface For Center Of Workspace Interaction, Rick Komerska, Colin Ware, Matt D. Plumlee
Center for Coastal and Ocean Mapping
We build upon a new interaction style for 3D interfaces, called the center of workspace interaction. This style of interaction is defined with respect to a central fixed point in 3D space, conceptually within arm's length of the user. For demonstration, we show a haptically enabled fish tank VR that utilizes a set of interaction widgets to support rapid navigation within a large virtual space. The fish tank VR refers to the creation of a small but high quality virtual reality that combines a number of technologies, such as head-tracking and stereo glasses, to their mutual advantage
Quantitative Ground-Truthing Of Habitat Characteristics Using Video Mosaic Images, Randy G. Cutter Jr., Yuri Rzhanov, Larry A. Mayer
Quantitative Ground-Truthing Of Habitat Characteristics Using Video Mosaic Images, Randy G. Cutter Jr., Yuri Rzhanov, Larry A. Mayer
Center for Coastal and Ocean Mapping
No abstract provided.
A Method For The Perceptual Optimization Of Complex Visualizations, Donald H. House, Colin Ware
A Method For The Perceptual Optimization Of Complex Visualizations, Donald H. House, Colin Ware
Center for Coastal and Ocean Mapping
A common problem in visualization applications is the display of one surface overlying another. Unfortunately, it is extremely difficult to do this clearly and effectively. Stereoscopic viewing can help, but in order for us to be able to see both surfaces simultaneously, they must be textured, and the top surface must be made partially transparent. There is also abundant evidence that all textures are not equal in helping to reveal surface shape, but there are no general guidelines describing the best set of textures to be used in this way. What makes the problem difficult to perceptually optimize is that …
Multibeam Volume Acoustic Backscatter Imagery And Reverberation Measurements In The Northeastern Gulf Of Mexico, Timoth C. Gallaudet, Christian De Moustier
Multibeam Volume Acoustic Backscatter Imagery And Reverberation Measurements In The Northeastern Gulf Of Mexico, Timoth C. Gallaudet, Christian De Moustier
Center for Coastal and Ocean Mapping
Multibeam volume acoustic backscatterimagery and reverberation measurements are derived from data collected in 200-m-deep waters in the northeastern Gulf of Mexico, with the Toroidal Volume Search Sonar (TVSS), a 68-kHz cylindrical sonar operated by the U.S. Navy’s Coastal System Station. The TVSS’s 360-degree vertical imaging plane allows simultaneous identification of multiple volume scattering sources and their discrimination from backscatter at the sea surface or the seafloor. This imaging capability is used to construct a three-dimensional representation of a pelagic fish school near the bottom. Scattering layers imaged in the mixed layer and upper thermocline are attributed to assemblages of epipelagic …
Automated Texture-Based Segmentation Of Multibeam Sonar Bathymetry Data For Benthic Habitat Mapping In The Piscataqua River, New Hampshire, Randy G. Cutter Jr., Yuri Rzhanov, Larry A. Mayer
Automated Texture-Based Segmentation Of Multibeam Sonar Bathymetry Data For Benthic Habitat Mapping In The Piscataqua River, New Hampshire, Randy G. Cutter Jr., Yuri Rzhanov, Larry A. Mayer
Center for Coastal and Ocean Mapping
No abstract provided.
In Situ Measurement Of Geoacoustic Properties: An Example From The Onr Mine Burial Program, Martha's Vineyard Coastal Observatory, Barbara J. Kraft, Larry A. Mayer, P. Simpkin, John A. Goff, Chris Jenkins
In Situ Measurement Of Geoacoustic Properties: An Example From The Onr Mine Burial Program, Martha's Vineyard Coastal Observatory, Barbara J. Kraft, Larry A. Mayer, P. Simpkin, John A. Goff, Chris Jenkins
Center for Coastal and Ocean Mapping
No abstract provided.
Rates Of Sedimentation In The Central Arctic Ocean, Jan Backman, Martin Jakobsson, Reidar Lovlie, Leonid Polyak
Rates Of Sedimentation In The Central Arctic Ocean, Jan Backman, Martin Jakobsson, Reidar Lovlie, Leonid Polyak
Center for Coastal and Ocean Mapping
The Arctic Ocean is presently undergoing geoscientific investigations of the type that occurred during the late 1940's through 1960's in the Atlantic, Indian and Pacific oceans. Seismic reflection and refraction data are scarce in the Arctic Ocean and large areas are virtually unsampled with respect to piston or gravity coring. The vast majority of available cores are less than10 m in length and largely lack biostratigraphically useful calcareous and siliceous microfossils. No drill cores exist from the ridges or deep basins in the central Arctic Ocean. Considering the limited geophysical and geological data available, it is not surprising that current …