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description Publicationkeyboard_double_arrow_right Other literature type 1994 FrancePublisher:Geological Society of America Authors: Auzende, Jean-Marie; Pelletier, Bernard; Lafoy, Y.;Auzende, Jean-Marie; Pelletier, Bernard; Lafoy, Y.;Recent work on the North Fiji Basin axial spreading ridge and on the active propagating ridge located west of the Fiji Islands has established the existence of two active spreading ridges that have been functioning synchronously in the basin since at least 1 or 1.5 Ma. This hypothesis is tested and the kinematics of the twin active ridges are refined further on the basis of analysis of bathymetric and magnetic data.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1130/0091-7613(1994)022<0063:tasrit>2.3.co;2&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.euAccess Routesbronze 39 citations 39 popularity Average influence Top 10% impulse Top 10% Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1130/0091-7613(1994)022<0063:tasrit>2.3.co;2&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type 2019 France EnglishAuthors: Bergsma, E. W. J.; Almar, Rafaël; de Almeida, L. P. M.; Sall, M.;Bergsma, E. W. J.; Almar, Rafaël; de Almeida, L. P. M.; Sall, M.;Commercial Unmanned Areal Vehicles (UAV) are taking a flight: it has never been more accessible to own an UAV and as easy to operate one, e.g. a drone. For coastal monitoring these advances open a new world of monitoring such as inter-tidal beach topography through Structure for Motion. This paper aims to 1) show the potential of the UAV-based depth inversion with 2) limited georeferencing resources for rectification, comparing traditional field-based GCPs and fully remote standalone methods (few local GCPs and Google Earth derived GCPs) and a 3) novel automated error reduction inclusion for the breakpoint location. Unlike with shore-based cameras, image stabilisation is key airborne bathymetry estimation. At places that are hard to reach it is not always possible to get ground control points. We discuss the use of Google Earth to obtain ground control points. In all video-derived bathymetries obtained in this work, great overestimation of the depth is found around wave breaking which is often linked to a phase shift in pixel intensity (dark wave front to white foam). A new method to overcome phase shift issues around breaking is presented that results in a significant error reduction of 58% around the break point.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=od_______932::fd069e0a93c648b6df79f9b217d34fa3&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type 2020 France EnglishAuthors: Abessolo, G. O.; Almar, Rafaël; Bonou, F.; Bergsma, E.;Abessolo, G. O.; Almar, Rafaël; Bonou, F.; Bergsma, E.;The accuracy of bathymetric measurements is crucial, especially to understand coastal processes. Video-based depth inversion methods have been widely developed in recent years, but they remain noisy, with typical errors due to the breakpoint optical and non-linear effects. Among the spectral and temporal approaches to video depth inversion, only the spectral approach applies an error criterion to identify erroneous data. Here, two error proxies are assimilated for the first time in the temporal approach, using a Kalman filter applied to 3.5 years (February 2013 to September 2016) of video images. Differences between filtered and unfiltered bathymetries were observed to be correlated with the proxies considered. A validation with field data on a 10-day experiment is performed between the original bathymetries and the filtered bathymetries. The results indicate that the mean square error can be reduced by at least 30%. Both proxies show good ability to correct depth estimates. Although the results are promising, validation of these approximations must be performed under various hydrodynamic and atmospheric conditions.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=od_______932::dc02b0ef8342d30ff4b311502f5400a2&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type 2019 France EnglishAuthors: Almar, Rafaël; Bergsma, E. W. J.; Maisongrande, P.; de Almeida, L. P. M.;Almar, Rafaël; Bergsma, E. W. J.; Maisongrande, P.; de Almeida, L. P. M.;This article shows the capacity do derive depth using the sub metric Pleiades satellite mission (Airbus/CNES) in persistent mode, which allows acquiring a sequence of images (12 images) at a regional scale (similar to 100 km(2)). To derive depths, a spatiotemporal cross-correlation method for estimating wave velocity and inverse bathymetry is presented and applied to the 12-image sequence. A good agreement is found with in-situ bathymetry measurements obtained during the COMBI 2017 Capbreton experiment (correlation of 0.8, RMSE = 1.4 m). Depth estimate saturation is found for depths > 35 m, mainly in a deep canyon just off the coast located in front of the entrance to Capbreton harbour. The image sequence is used to study the sensitivity of the number of images. The results show that the accuracy increases with the number of images in the sequence and with a fine resolution. Despite their noisy nature, newly available time-updated satellite bathymetries can be used to understand coastal evolution at several scales and improve risk mitigation strategies through modelling.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=od_______932::f6cc23f16a188b0486e8a93d156bbe7c&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Conference object , Other literature type 2010 FrancePublisher:SPIE Authors: Minghelli-Roman, A.; Dupouy, Cécile; Chevillon, C.; Douillet, Pascal;Minghelli-Roman, A.; Dupouy, Cécile; Chevillon, C.; Douillet, Pascal;doi: 10.1117/12.870729
No map of the sea floor is available yet on the whole lagoon of New Caledonia. We tried to validate a method to map it with MeRIS images on the south western part of the lagoon. The non-linear effect of water column light attenuation can then be corrected to obtain the absolute reflectance of the seabed. Light attenuation by the water column can be determined by comparing the radiance of standard features on the seabed at different depth. Bathymetry can also be determined by measuring the relative reflectance of the seabed in green and red light spectral bands. Once the effect of attenuation has been removed, a supervised classification can be applied in order to obtain the location of each item on the sea floor. Validations are operated with ground measurements of depth, spectral profiles and some available maps.
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You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1117/12.870729&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu3 citations 3 popularity Average influence Average impulse Average Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1117/12.870729&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Other literature type 1991 FrancePublisher:American Geophysical Union (AGU) Authors: Baudry, N.; Calmant, Stéphane;Baudry, N.; Calmant, Stéphane;doi: 10.1029/91gl01341
We develop a complete set of algorithms to perform 3D modelling of seamount bathymery from satellite altimetry. The first stage of the data processing consists in gridding the geoid: to account for the long wavelength errors geoid heights are first bias‐adjusted at cross‐overs. Then a collocation on a regular grid is performed, accounting for the altimeter errors. In a second stage, geoid heights are converted into bathymetry. No simplifying assumption on the shape and location of the bathymetry highs is necessary. Bathymetric uncertainties due to the data sampling and the parameters of the mechanical and crustal models are evaluated.
Horizon / Pleins tex... arrow_drop_down Geophysical Research LettersArticle . 1991 . Peer-reviewedLicense: Wiley Online Library User AgreementData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1029/91gl01341&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu39 citations 39 popularity Top 10% influence Top 10% impulse Average Powered by BIP!more_vert Horizon / Pleins tex... arrow_drop_down Geophysical Research LettersArticle . 1991 . Peer-reviewedLicense: Wiley Online Library User AgreementData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1029/91gl01341&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type , Article 1996 FrancePublisher:Springer Science and Business Media LLC Auzende, Jean-Marie; Kroenke, L.; Collot, Jean-Yves; Lafoy, Y.; Pelletier, Bernard;doi: 10.1007/bf00286082
New bathymetric and geophysical data were collected in the region east of the island of Malaita during the SOPACMAPS II cruise of the French research vessel L'Atalante. This region, part of the Malaita Anticlinorium was interpreted as a piece of oceanic crust from the Ontong Java Plateau obducted over the old Solomon Islands arc during collision between the Pacific and Australian plates. It has been generally accepted that convergent motion between the Australia and Pacific plates since the Late Miocene was absorbed exclusively along the San Cristobal trench, southwest of the Solomon Islands Arc. Bathymetry, imagery, and geophysical data (magnetism, gravity, seismic) acquired during the SOPACMAPS II survey allow us to classify the successive parallel ridges mapped within the region as being recent volcanic, oceanic crust, or deformed sedimentary ridges. Seismic profiling provides evidence of successive compressive events along the Malaita margin caused by the relative motion between the Solomon Islands and the Pacific plate. The main phase of convergence probably occurred during Oligocene-early Miocene time, but some relative motion between the two domains are still being absorbed along the East Malaita boundary. The existence of active faulting in the sedimentary cover throughout the region and the present-day deformation of the outer sedimentary ridge is a good illustration of this phenomenon. (Résumé d'auteur)
Horizon / Pleins tex... arrow_drop_down Marine Geophysical ResearchArticle . 1996 . Peer-reviewedLicense: Springer TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1007/bf00286082&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu8 citations 8 popularity Average influence Average impulse Average Powered by BIP!more_vert Horizon / Pleins tex... arrow_drop_down Marine Geophysical ResearchArticle . 1996 . Peer-reviewedLicense: Springer TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1007/bf00286082&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Other literature type 1994 FrancePublisher:Elsevier BV Auzende, Jean-Marie; Gracia-Mont, E.; Bendel, V.; Huchon, P.; Lafoy, Y; Lagabrielle, Y.; Alteriis, G. de; Tanahashi, M.;Auzende, J.-M., Grficia-Mont, E., Bendel, V., Huchon, P., Lafoy, Y., Lagabrielle, Y., De Alteriis, G. and Tanahashi, M., 1994. A possible triple junction at 14°50'S on the North Fiji Basin Ridge (Southwest Pacific)?. In: J.-M. Auzende and T. Urabe (Editors), North Fiji Basin: SXARNER French Japanese Program. Mar. Geol., 116: 25-35. Recent full coverage bathymetric and geophysical surveys (Yokosuka 90 and 91), carried out in the framework of the STARMER Japanese-French joint project, reveal details of the structure of the N160 ° segment of the North Fiji Basin Ridge. Despite its intermediate spreading rate this segment shows a "slow spreading" type morphology with steep 1000 m high walls reaching an axial depth of 4000 m. Its northern tip at 14°50'S is a complex area involving several plates boundaries. This domain can be interpreted either as a complex boundary between two plates, or as a new triple junction, symmetrical with the 16°50'S Triple Junction characterizing its southern tip. In either case, the complexity of the spreading ridge geometry in this area illustrates the instability of the accretionary geometry due to the deformation of the whole North Fiji Basin between the much larger Indo-Australian and Pacific plates.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/0025-3227(94)90166-x&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu7 citations 7 popularity Average influence Average impulse Average Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/0025-3227(94)90166-x&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Other literature type 1981 France FrenchAuthors: Lemasson, L.; Pages, J.; Dufour, P.;Lemasson, L.; Pages, J.; Dufour, P.;handle: 1834/24414
An estimation of the currents in the Biétri bay is given (tidal currents and currents due to the wind). They are lower than 10 cm.s-1 in the whole lagoon, and near of 5 cm.s-1 in the eastern part. The measures of salinity and tidal observations give the average rate of water renewal, respectively 0.20 and 0.14 d-1 in the central and eastern areas.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=1834/24414&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.euAccess RoutesGreen 0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=1834/24414&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Other literature type 1994 FrancePublisher:Oxford University Press (OUP) Authors: Calmant, Stéphane;Calmant, Stéphane;SUMMARY Altimetric measurements of sea-surface heights have long been used to locate uncharted marine features. Newly available data sets (Geosat-GM, ERS-1 and Topex/Poseidon), now allow the topography of submarine volcanoes to be accurately restored and a method based upon inverse modelling is presented in this paper. This method allows a joint assimilation of altimetric data and shipborne profiles of bathymetry and/or gravity anomalies when available. Furthermore, uncertainties can be computed together with the topography, which constitutes a noticeable improvement since these parameters are still missing in the usual bathymetric data bases. Tests are performed using simulated data, in order to characterize the errors which may or must occur with the modelled topography of a previously unknown volcano, in particular the errors due to data uncertainties and the lack of precise knowledge of sensitive parameters that are used in the modelling. These errors can be maintained under the 100 m level (rms) for altimetric data with a measurement noise of 5 cm (rms) or less, which is achieved for Geosat, ERS-1 and Topex/Poseidon altimeters. An example of inversion of Seasat data is presented in the case of a seamount in French Polynesia.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1111/j.1365-246x.1994.tb00133.x&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.euAccess Routesbronze 33 citations 33 popularity Top 10% influence Top 10% impulse Average Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1111/j.1365-246x.1994.tb00133.x&type=result"></script>'); --> </script>
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description Publicationkeyboard_double_arrow_right Other literature type 1994 FrancePublisher:Geological Society of America Authors: Auzende, Jean-Marie; Pelletier, Bernard; Lafoy, Y.;Auzende, Jean-Marie; Pelletier, Bernard; Lafoy, Y.;Recent work on the North Fiji Basin axial spreading ridge and on the active propagating ridge located west of the Fiji Islands has established the existence of two active spreading ridges that have been functioning synchronously in the basin since at least 1 or 1.5 Ma. This hypothesis is tested and the kinematics of the twin active ridges are refined further on the basis of analysis of bathymetric and magnetic data.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1130/0091-7613(1994)022<0063:tasrit>2.3.co;2&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.euAccess Routesbronze 39 citations 39 popularity Average influence Top 10% impulse Top 10% Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1130/0091-7613(1994)022<0063:tasrit>2.3.co;2&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type 2019 France EnglishAuthors: Bergsma, E. W. J.; Almar, Rafaël; de Almeida, L. P. M.; Sall, M.;Bergsma, E. W. J.; Almar, Rafaël; de Almeida, L. P. M.; Sall, M.;Commercial Unmanned Areal Vehicles (UAV) are taking a flight: it has never been more accessible to own an UAV and as easy to operate one, e.g. a drone. For coastal monitoring these advances open a new world of monitoring such as inter-tidal beach topography through Structure for Motion. This paper aims to 1) show the potential of the UAV-based depth inversion with 2) limited georeferencing resources for rectification, comparing traditional field-based GCPs and fully remote standalone methods (few local GCPs and Google Earth derived GCPs) and a 3) novel automated error reduction inclusion for the breakpoint location. Unlike with shore-based cameras, image stabilisation is key airborne bathymetry estimation. At places that are hard to reach it is not always possible to get ground control points. We discuss the use of Google Earth to obtain ground control points. In all video-derived bathymetries obtained in this work, great overestimation of the depth is found around wave breaking which is often linked to a phase shift in pixel intensity (dark wave front to white foam). A new method to overcome phase shift issues around breaking is presented that results in a significant error reduction of 58% around the break point.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=od_______932::fd069e0a93c648b6df79f9b217d34fa3&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type 2020 France EnglishAuthors: Abessolo, G. O.; Almar, Rafaël; Bonou, F.; Bergsma, E.;Abessolo, G. O.; Almar, Rafaël; Bonou, F.; Bergsma, E.;The accuracy of bathymetric measurements is crucial, especially to understand coastal processes. Video-based depth inversion methods have been widely developed in recent years, but they remain noisy, with typical errors due to the breakpoint optical and non-linear effects. Among the spectral and temporal approaches to video depth inversion, only the spectral approach applies an error criterion to identify erroneous data. Here, two error proxies are assimilated for the first time in the temporal approach, using a Kalman filter applied to 3.5 years (February 2013 to September 2016) of video images. Differences between filtered and unfiltered bathymetries were observed to be correlated with the proxies considered. A validation with field data on a 10-day experiment is performed between the original bathymetries and the filtered bathymetries. The results indicate that the mean square error can be reduced by at least 30%. Both proxies show good ability to correct depth estimates. Although the results are promising, validation of these approximations must be performed under various hydrodynamic and atmospheric conditions.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=od_______932::dc02b0ef8342d30ff4b311502f5400a2&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type 2019 France EnglishAuthors: Almar, Rafaël; Bergsma, E. W. J.; Maisongrande, P.; de Almeida, L. P. M.;Almar, Rafaël; Bergsma, E. W. J.; Maisongrande, P.; de Almeida, L. P. M.;This article shows the capacity do derive depth using the sub metric Pleiades satellite mission (Airbus/CNES) in persistent mode, which allows acquiring a sequence of images (12 images) at a regional scale (similar to 100 km(2)). To derive depths, a spatiotemporal cross-correlation method for estimating wave velocity and inverse bathymetry is presented and applied to the 12-image sequence. A good agreement is found with in-situ bathymetry measurements obtained during the COMBI 2017 Capbreton experiment (correlation of 0.8, RMSE = 1.4 m). Depth estimate saturation is found for depths > 35 m, mainly in a deep canyon just off the coast located in front of the entrance to Capbreton harbour. The image sequence is used to study the sensitivity of the number of images. The results show that the accuracy increases with the number of images in the sequence and with a fine resolution. Despite their noisy nature, newly available time-updated satellite bathymetries can be used to understand coastal evolution at several scales and improve risk mitigation strategies through modelling.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=od_______932::f6cc23f16a188b0486e8a93d156bbe7c&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Conference object , Other literature type 2010 FrancePublisher:SPIE Authors: Minghelli-Roman, A.; Dupouy, Cécile; Chevillon, C.; Douillet, Pascal;Minghelli-Roman, A.; Dupouy, Cécile; Chevillon, C.; Douillet, Pascal;doi: 10.1117/12.870729
No map of the sea floor is available yet on the whole lagoon of New Caledonia. We tried to validate a method to map it with MeRIS images on the south western part of the lagoon. The non-linear effect of water column light attenuation can then be corrected to obtain the absolute reflectance of the seabed. Light attenuation by the water column can be determined by comparing the radiance of standard features on the seabed at different depth. Bathymetry can also be determined by measuring the relative reflectance of the seabed in green and red light spectral bands. Once the effect of attenuation has been removed, a supervised classification can be applied in order to obtain the location of each item on the sea floor. Validations are operated with ground measurements of depth, spectral profiles and some available maps.
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You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1117/12.870729&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu3 citations 3 popularity Average influence Average impulse Average Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1117/12.870729&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Other literature type 1991 FrancePublisher:American Geophysical Union (AGU) Authors: Baudry, N.; Calmant, Stéphane;Baudry, N.; Calmant, Stéphane;doi: 10.1029/91gl01341
We develop a complete set of algorithms to perform 3D modelling of seamount bathymery from satellite altimetry. The first stage of the data processing consists in gridding the geoid: to account for the long wavelength errors geoid heights are first bias‐adjusted at cross‐overs. Then a collocation on a regular grid is performed, accounting for the altimeter errors. In a second stage, geoid heights are converted into bathymetry. No simplifying assumption on the shape and location of the bathymetry highs is necessary. Bathymetric uncertainties due to the data sampling and the parameters of the mechanical and crustal models are evaluated.
Horizon / Pleins tex... arrow_drop_down Geophysical Research LettersArticle . 1991 . Peer-reviewedLicense: Wiley Online Library User AgreementData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1029/91gl01341&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu39 citations 39 popularity Top 10% influence Top 10% impulse Average Powered by BIP!more_vert Horizon / Pleins tex... arrow_drop_down Geophysical Research LettersArticle . 1991 . Peer-reviewedLicense: Wiley Online Library User AgreementData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1029/91gl01341&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Other literature type , Article 1996 FrancePublisher:Springer Science and Business Media LLC Auzende, Jean-Marie; Kroenke, L.; Collot, Jean-Yves; Lafoy, Y.; Pelletier, Bernard;doi: 10.1007/bf00286082
New bathymetric and geophysical data were collected in the region east of the island of Malaita during the SOPACMAPS II cruise of the French research vessel L'Atalante. This region, part of the Malaita Anticlinorium was interpreted as a piece of oceanic crust from the Ontong Java Plateau obducted over the old Solomon Islands arc during collision between the Pacific and Australian plates. It has been generally accepted that convergent motion between the Australia and Pacific plates since the Late Miocene was absorbed exclusively along the San Cristobal trench, southwest of the Solomon Islands Arc. Bathymetry, imagery, and geophysical data (magnetism, gravity, seismic) acquired during the SOPACMAPS II survey allow us to classify the successive parallel ridges mapped within the region as being recent volcanic, oceanic crust, or deformed sedimentary ridges. Seismic profiling provides evidence of successive compressive events along the Malaita margin caused by the relative motion between the Solomon Islands and the Pacific plate. The main phase of convergence probably occurred during Oligocene-early Miocene time, but some relative motion between the two domains are still being absorbed along the East Malaita boundary. The existence of active faulting in the sedimentary cover throughout the region and the present-day deformation of the outer sedimentary ridge is a good illustration of this phenomenon. (Résumé d'auteur)
Horizon / Pleins tex... arrow_drop_down Marine Geophysical ResearchArticle . 1996 . Peer-reviewedLicense: Springer TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1007/bf00286082&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu8 citations 8 popularity Average influence Average impulse Average Powered by BIP!more_vert Horizon / Pleins tex... arrow_drop_down Marine Geophysical ResearchArticle . 1996 . Peer-reviewedLicense: Springer TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1007/bf00286082&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Other literature type 1994 FrancePublisher:Elsevier BV Auzende, Jean-Marie; Gracia-Mont, E.; Bendel, V.; Huchon, P.; Lafoy, Y; Lagabrielle, Y.; Alteriis, G. de; Tanahashi, M.;Auzende, J.-M., Grficia-Mont, E., Bendel, V., Huchon, P., Lafoy, Y., Lagabrielle, Y., De Alteriis, G. and Tanahashi, M., 1994. A possible triple junction at 14°50'S on the North Fiji Basin Ridge (Southwest Pacific)?. In: J.-M. Auzende and T. Urabe (Editors), North Fiji Basin: SXARNER French Japanese Program. Mar. Geol., 116: 25-35. Recent full coverage bathymetric and geophysical surveys (Yokosuka 90 and 91), carried out in the framework of the STARMER Japanese-French joint project, reveal details of the structure of the N160 ° segment of the North Fiji Basin Ridge. Despite its intermediate spreading rate this segment shows a "slow spreading" type morphology with steep 1000 m high walls reaching an axial depth of 4000 m. Its northern tip at 14°50'S is a complex area involving several plates boundaries. This domain can be interpreted either as a complex boundary between two plates, or as a new triple junction, symmetrical with the 16°50'S Triple Junction characterizing its southern tip. In either case, the complexity of the spreading ridge geometry in this area illustrates the instability of the accretionary geometry due to the deformation of the whole North Fiji Basin between the much larger Indo-Australian and Pacific plates.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/0025-3227(94)90166-x&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu7 citations 7 popularity Average influence Average impulse Average Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/0025-3227(94)90166-x&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Other literature type 1981 France FrenchAuthors: Lemasson, L.; Pages, J.; Dufour, P.;Lemasson, L.; Pages, J.; Dufour, P.;handle: 1834/24414
An estimation of the currents in the Biétri bay is given (tidal currents and currents due to the wind). They are lower than 10 cm.s-1 in the whole lagoon, and near of 5 cm.s-1 in the eastern part. The measures of salinity and tidal observations give the average rate of water renewal, respectively 0.20 and 0.14 d-1 in the central and eastern areas.
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You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=1834/24414&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.euAccess RoutesGreen 0 citations 0 popularity Average influence Average impulse Average Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=1834/24414&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Other literature type 1994 FrancePublisher:Oxford University Press (OUP) Authors: Calmant, Stéphane;Calmant, Stéphane;SUMMARY Altimetric measurements of sea-surface heights have long been used to locate uncharted marine features. Newly available data sets (Geosat-GM, ERS-1 and Topex/Poseidon), now allow the topography of submarine volcanoes to be accurately restored and a method based upon inverse modelling is presented in this paper. This method allows a joint assimilation of altimetric data and shipborne profiles of bathymetry and/or gravity anomalies when available. Furthermore, uncertainties can be computed together with the topography, which constitutes a noticeable improvement since these parameters are still missing in the usual bathymetric data bases. Tests are performed using simulated data, in order to characterize the errors which may or must occur with the modelled topography of a previously unknown volcano, in particular the errors due to data uncertainties and the lack of precise knowledge of sensitive parameters that are used in the modelling. These errors can be maintained under the 100 m level (rms) for altimetric data with a measurement noise of 5 cm (rms) or less, which is achieved for Geosat, ERS-1 and Topex/Poseidon altimeters. An example of inversion of Seasat data is presented in the case of a seamount in French Polynesia.
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You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1111/j.1365-246x.1994.tb00133.x&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.euAccess Routesbronze 33 citations 33 popularity Top 10% influence Top 10% impulse Average Powered by BIP!more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1111/j.1365-246x.1994.tb00133.x&type=result"></script>'); --> </script>
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