Consulta: subjectFacets:"Sedimentology"
Registros recuperados: 28
Data/hora: 13/06/2024 04:46:11

Instabilites sous-marine etudiees par submersibles
Provedor de dados: 5
Autores: Savoye, Bruno.
Sediment instability appears to be important as a part of global sedimentary budget. Among the various types of sedimentary instabilities, submarine slides are probably the most spectacular and the hardest to study and predict, although their consequences on human and industrial marine activities can be dramatic. IFREMER is conducting a research project on this topic. An area off Nice (France) has been particularly studied because of its recent activity. Mapping and instability area detection have been carried out. With the possibility of direct interactive observation and highly accurate submarine in -situ operation, the submersible is an extremely efficient tool for sediment studies, but diving purposes have to be precisely defined to provide useful...
Tipo: Text
Palavras-chave: Sediments; Instability; Sedimentology; Sedimentary structures; Ocean floor; Marine technology; Geology; Submersibles; Unmanned vehicles.
Ano: 1990
URL: http://archimer.ifremer.fr/doc/1990/acte-1150.pdf

Les peuplements benthiques du plateau insulaire de la Martinique et des zones bathyales adjacentes. Cas particulier de la malacofaune
Provedor de dados: 5
Autores: Paulmier, Gerard; Durand, Francoise.
Several oceanographic surveys in Martinique waters with, as main objectives, either geological mapping and evaluating marine aggregate resources of research into deep water carcinologie resources, nafe produced interesting informtion on benthic pppulations situated from the infralittoral to the bathyal shelf, for the wole of faunistic groups and more specifically for the malacofauna. The distribution of the various faunistic group has been analysed in function to the bathymetric, edaphic and possibly, thermic factors. The infralittoral zones, up to the 20 metres isobath, and circalittoral, between 60  and 80 metres, are known to have the richest populations. Corals, sponges, polychaete annelida and molluscs are the best represented, numerically as well as...
Tipo: Text
Palavras-chave: Ecologie; Sédimentologie; Bathymétrie; Peuplements; Benthos; Invertebrés; Communautés; Bivalves; Gastéropodes; Ecology; Sedimentology; Bathymetry; Settelment; Benthos; Invertebrates; Molluscs; Communities; Bivalvia; Gastropoda.
Ano: 1997
URL: https://archimer.ifremer.fr/doc/00480/59191/61880.pdf

Etude sédimentaire de la baie de Quiberon : la zone ostréicole en eau profonde et ses abords
Provedor de dados: 5
Autores: Lemoine, Gérard.
Tipo: Text
Palavras-chave: Hydrobiology; Hydrodynamic; Sedimentology; Oyster culture zone.
Ano: 1989
URL: http://archimer.ifremer.fr/doc/1989/rapport-2210.pdf

Pycaso - Avril 2000. Étude biomorphosédimentaire du domaine marin côtier entre Dieppe et Criel-sur-Mer (Seine-Maritime ; France)
Provedor de dados: 5
Autores: Dreves, Luc; Clabaut, Philippe; Chevalier, Claire.
Environnemental monitoring of the PENLY nuclear power plant takes into account, every fourth year, fauna and sedimentology studies of the sea floor between Dieppe and Criel-sur-Mer (Eastern Channel, France).
Tipo: Text
Palavras-chave: Centrale nucléaire; Penly; Surveillance; Benthos; Faune; Morphologie; Sédimentologie; Monitoring; Nuclear power plant; Penly; Benthos; Fauna; Morphology; Sedimentology.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/00005/11660/8320.pdf

Carbonate mounds of the Moroccan Mediterranean margin: Facies and environmental controls
Provedor de dados: 5
Autores: Terhzaz, Loubna; Hamoumi, Naima; Spezzaferri, Silvia; Lotfi, El Mostapha; Henriet, Jean-pierre.
Sedimentological and geochemical studies of boxcores from the Brittlestar Ridge I and Cabliers carbonate mounds, along the Moroccan Mediterranean margin, show that sediments are composed of cold water scleratian corals and micritic mud, muddy micrite or muddy allochem limestone matrix, outlining seven different facies that can be attributed to “cluster reefs”. The mixed siliciclastic/carbonate sediments have been derived from both extra- and intrabasinal sources. Extra-basinal sources may be the geological formations outcropping in the Moroccan hinterland and Sahara, the latter including corals and associated bioclasts. Sediments were transported by wind and rivers and redistributed by bottom currents and local upwelling. Our results confirm the role of...
Tipo: Text
Palavras-chave: Carbonate mounds; Cold water corals; Sedimentology; Sedimentary geochemistry; Moroccan Mediterranean margin.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00445/55699/57370.pdf

Oceanologic study of an open coastal area in the Ionian sea with emphasis on its benthic fauna and some zoogeographical remarks
Provedor de dados: 5
Autores: Zenetos, A; Christianidis, S; Pancucci, Ma; Simboura, N; Tziavos, C.
The macrobenthic faunal composition, sedimentology and physical characteristics were investigated in an open coastal area of the Greek Ionian Sea. Hydrographic parameters were recorded at 26 stations using a CTD profiler during nine cruises performed between 1990 and 1991, while benthic samples were collected in November 1990 and April 1991 at 22 stations with the aid of a Ponar grab. Macrobenthic variety indicated an area of high scientific interest : 351 species in all, 18 of which are new to the Creek fauna. Furthermore, 10 species are previously unrecorded in the Eastern Mediterranean. Of the biological indices estimated, species richness was comparable to that of other open Greek areas, while population density seemed to be a function of a) depth and...
Tipo: Text
Palavras-chave: Macrobenthos; Zoogeography; Physical oceanography; Sedimentology; Ionian Sea.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/00093/20408/18075.pdf

Seasonal sediment dynamics of the Marennes Oleron Bay : characterisation of superficial sediment textural properties and rheophysics
Provedor de dados: 5
Autores: Kervella, Stephane; Robert, Serge; Pantet, Anne; Jarny, Sebastien.
Tipo: Text
Palavras-chave: Sedimentology; Marennes Oleron Bay.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/00175/28604/27025.pdf

Volcanoes and climate: the triggering of preboreal Jökulhlaups in Iceland
Provedor de dados: 5
Autores: Van Vliet-lanoë, Brigitte; Knudsen, Oskar; Guðmundsson, Agust; Guillou, Hervé; Chazot, Gilles; Langlade, Jessica; Liorzou, Celine; Nonnotte, Philippe.
The Early Holocene (12–8.2 cal ka) deglaciation and pulsed warming was associated in Iceland with two major generations of jökulhlaups around the Vatna ice-cap (Vatnajökull), at ca 11.4–11.2 cal ka and ca 10.4–9.9 cal ka, and major tephra emissions from the Grímsvötn and Bárðarbunga subglacial volcanoes. The earliest flood events were recorded inland during the Middle Younger Dryas and their deposits were overlain by the Early Preboreal Vedde Ash (11.8 cal ka). The first Holocene flood events (ca 11.4–11.2 cal ka) are issued from a glacial advance. The second, and major, set of floods was partly driven by the Erdalen cold events and advances (10.1–9.7 10Be ka) initially issued from the Bárðarbunga (10.4, 10.1–9.9 ka) and Grímsvötn volcanoes (Saksunarvatn...
Tipo: Text
Palavras-chave: Holocene; Deglaciation; Iceland; Geomorphology; Glacial; Flood; Sedimentology; Tephra; Glacio-isostatic rebound; Permafrost; Saksunarvatn event; Askja S.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00613/72489/74845.pdf

The morpho-sedimentology of an artificial roadstead (Cherbourg, France)
Provedor de dados: 5
Autores: Gregoire, G.; Méar, Y.; Poizot, E.; Marion, C.; Murat, A.; Hebert, B.
Because of its size and geographical position, the Cherbourg roadstead appears as a favourable site for Marine Renewable Energy (MRE) industry. As a result, Cherbourg harbour has undergone profound changes (2015 and 2016) due to the installation of industrial infrastructures to service the needs of expanding MRE further offshore. However, little is known about the morpho-sedimentary distribution and associated dynamics of seabed sediments before and after harbour transformations. This study focuses on sedimentary dynamics using detailed morphological and sedimentological analyses based on data acquired before changes (2012). The main map includes a unique bathymetric map (1:35,000) and sedimentary maps showing the percentage of the characteristic grain...
Tipo: Text
Palavras-chave: Morphology; Sedimentology; Morphodynamic; Granulometry; Bathymetry; Cherbourg roadstead.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00515/62638/67005.pdf

Independent tephrochronological evidence for rapid and synchronous oceanic and atmospheric temperature rises over the Greenland stadial-interstadial transitions between ca. 32 and 40 ka b2k
Provedor de dados: 5
Autores: Berben, Sarah M.p.; Dokken, Trond M.; Abbott, Peter M.; Cook, Eliza; Sadatzki, Henrik; Simon, Margit H; Jansen, Eystein.
Understanding the dynamics that drove past abrupt climate changes, such as the Dansgaard-Oeschger (DO) events, depends on combined proxy evidence from disparate archives. To identify leads, lags and synchronicity between different climate system components, independent and robust chronologies are required. Cryptotephrochronology is a key geochronological tool as cryptotephra horizons can act as isochrons linking disparate and/or distant records. Here, we investigated marine sediment core MD99-2284 from the Norwegian Sea to look for previously identified Greenland ice core cryptotephra horizons and define time-parallel markers between the archives. We explored potential secondary transport and depositional mechanisms that could hamper the isochronous...
Tipo: Text
Palavras-chave: Quaternary; Paleoclimatology; Paleoceanography; North Atlantic; Sedimentology; Marine cores; Ice cores; Cryptotephrochronology; DO-Events; Synchronization.
Ano: 2020
URL: https://archimer.ifremer.fr/doc/00622/73391/72606.pdf

Glacial reduction and millennial-scale variations in Drake Passage throughflow
Provedor de dados: 5
Autores: Lamy, Frank; Arz, Helge W.; Kilianc, Rolf; Lange, Carina B.; Lembke-jene, Lester; Wengler, Marc; Kaiser, Jerome; Baeza-urrea, Oscar; Hall, Ian R.; Harada, Naomi; Tiedemann, Ralf.
The Drake Passage (DP) is the major geographic constriction for the Antarctic Circumpolar Current (ACC) and exerts a strong control on the exchange of physical, chemical, and biological properties between the Atlantic, Pacific, and Indian Ocean basins. Resolving changes in the flow of circumpolar water masses through this gateway is, therefore, crucial for advancing our understanding of the Southern Ocean's role in global ocean and climate variability. Here, we reconstruct changes in DP throughflow dynamics over the past 65,000 y based on grain size and geochemical properties of sediment records from the southernmost continental margin of South America. Combined with published sediment records from the Scotia Sea, we argue for a considerable total...
Tipo: Text
Palavras-chave: Paleoceanography; Drake Passage; Antarctic Circumpolar Current; Glacial-interglacial changes; Sedimentology.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00351/46233/46119.pdf

An example of GIS potentiality for coastal zone management: preselection of submerged oyster culture areas near Marennes-Oleron (France)
Provedor de dados: 5
Autores: Durand, H.; Guillaumont, Brigitte; Loarer, Ronan; Loubersac, Lionel; Heral, Maurice; Prou, Jean.
The Charente Maritime coast, in central western France, is the most important area for oyster and mussel production in Europe. High density, in this restricted intertidal area, induces low growing rate and socio-economic difficulties. One of the possible solutions is to shift some oysters from intertidal area to submerged areas. Bathymetry, sedimentology, hydrodynamism, fisheries and administrative rules are some conditions which are considered to establish the better selection of potential zone. The successive steps of setting up the prototype of GIS are presented: digitized traditional data from charts, extracted data from grid models (hydrodynmaic model), merging of thematic covers, proposal of favorable areas. The results are discussed especially on...
Tipo: Text
Palavras-chave: GIS; Modelisation; Bathymetry; Sedimentology; Hydrodynamism; Marennes Oleron.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/00017/12784/9725.pdf

Etude biomorphosédimentaire du domaine marin côtier de Penly. Mission SONPEN - Mai 1992
Provedor de dados: 5
Autores: Dreves, Luc; Clabaut, Philippe; Chevalier, Claire.
The biological and sedimentology study of the sea floor between Dieppe and Le Treport (Eastern Channel, France) is a part of the environnemental monitoring of the Penly nuclear power plant. Every year, Hydrology, microbiology, phytoplankton, zooplankton, and fishing are studied.
Tipo: Text
Palavras-chave: Benthos; Biologie; Centrale nucleaire; Morphologie; Sedimentologie; Smveillance; Benthos; Biology; Morphology; Power plant; Sedimentology; Surveillance.
Ano: 1995
URL: https://archimer.ifremer.fr/doc/00465/57667/59869.pdf

Etude biomorphosédimentaire du domaine marin côtier entre Dieppe et Criel-sur-Mer (Seine-Maritime) – Morcaux - Avril et Mai 2014 - CNPE Penly
Provedor de dados: 5
Autores: Le Gac-abernot, Chantal; Clabaut, Philippe; Dreves, Luc; Gaffet, Jean-dominique.
Dans le cadre de la surveillance du milieu marin du site électronucléaire de PENLY (Seine-Maritime), le domaine benthique côtier de Dieppe à Criel-sur-mer a fait l’objet d’une prospection biomorphosédimentaire en avril et mai 2014, comme celles réalisées en 1988, 1992, 1996, 2000, 2008 et 2004.
Tipo: Text
Palavras-chave: Centrale nucléaire; Penly; Surveillance; Benthos; Faune; Sédiment; Monitoring; Penly; Power plant; Benthos; Fauna; Sedimentology.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00403/51448/52021.pdf

Mesures geotechniques par grand fond
Provedor de dados: 5
Autores: Cochonat, Pierre; Dansy, G; Leduc, Bernard; Meunier, Jacques; Harmegnies, Francois; Floury, L.
The mechanical behaviour of sediments is usually studied from laboratory core analyses which do not take into account the real state of in-situ stresses. Therefore, the aimed purpose is presently to determine the in-situ geotechnical properties which mainly depend on the relationship between fine-grained particles and intergranular fluids. At IFREMER, these achievements have been pursued in the framework of 2 scientific program: "Nodules and Sedimentary Processes and Instability on Slopes, for which surficial measurements were conducted on selected seafloor targets usually pre-defined from high resolution geophysical data." 2 kinds of instrumentation were developed in correlation to 2 different strategies of handling at sea. There is the instrumentation of...
Tipo: Text
Palavras-chave: Submarine cables; Deep sea mining; Offshore equipment; Geotechnology; Submersibles; Sedimentary structures; Sedimentology; Ferromanganese nodules; Instability; Marine technology; Sediments; Ocean floor; Deep water.
Ano: 1990
URL: http://archimer.ifremer.fr/doc/1990/acte-1157.pdf

The French Atlantic margin and deep-sea submarine systems
Provedor de dados: 5
Autores: Bourillet, Jean-francois; Zaragosi, S; Mulder, T.
The sedimentary infill of the Bay of Biscay off Ireland, UK, France and Spain took place in four phases. The last one (35 Ma to present) is characterised by gravitational, pelagic, contouritic and glacigenic processes leading to the setup of three deep sea systems. To the North, the Celtic and Armorican fans are fed by a "canyon-dominated" margin and its connection with the "Manche" palaeoriver, which drained a large area of western Europe. To the South, the Cap-Ferret fan results from the evolution of a "tectonic-dominated" margin and the erosion of the Pyrenee mountains.
Tipo: Text
Palavras-chave: Sedimentology; Geomorphologya; Deep sea; Bay of Biscay; French Atlantic margin.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-2137.pdf

Modélisation du transport sédimentaire et des interactions morphodynamiques par les courants de turbidité dans les canyons sous-marins. Application à la Méditerranée Occidentale
Provedor de dados: 5
Autores: Payo Payo, Marta.
Turbidity currents in submarine canyons are the main contribution for sediment transfer across the continental margins. Geological studies of submarine canyons and associated turbiditic systems for more than 30 years led to an extraordinary breakthrough in the understanding of how turbidite systems evolve. However, these studies remain limited to a posteriori interpretations, based on the distribution of deposits and morphological evidences. The overarching aim of this thesis is to apply a 2DH process-based model to simulate large-scale turbidity currents on two different submarine canyons in the western Mediterranean coast.The work in La Fonera canyon, in the Catalan margin, focuses on the modelling of sediment transport and accumulation resulting from...
Tipo: Text
Palavras-chave: Canyons sous-marins; Chalutage; Courants de turbidité; Forces de Coriolis; Hydrodynamique; Modélisation; Sédimentologie; Submarine canyons; Trawling; Turbidity current; Modelling; Hydrodynamics; Sedimentology; Coriolis forces.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00498/60919/64280.pdf

Morphodynamique et transferts sédimentaires au sein d'une baie mégatidale en comblement (Baie de Somme, Manche Est). Stratégie multi-échelles spatio-temporelles
Provedor de dados: 5
Autores: Michel, Charlotte.
The Baie de Somme is an infilling estuarine environment, controlled by intensive marine hydrodynamics forcing (megatidal tide and waves) and a small river flow. Morpho-sedimentary dynamics of this bay and sedimentary fluxes were studied at two spatial and temporal scales. I) At the scale of intertidal hydraulic dunes, studied during semi-diurnal and semi-lunar tidal cycles with neap tides (NT) and spring tides (ST). In this context, a strong forcing variability (winds, tide, waves) control sedimentary fluxes and morphodynamics evolutions of dunes (λ : 5-23 m ; H : 20-60 cm). These fluxes generally increase with tide and waves, inducing a net sediment transport to the east or west, according to the predominance of current (flood/ebb), which depends on the...
Tipo: Text
Palavras-chave: Marées; Sédimentation; Sédimentologie; Lutte contre Ensablement; Sédiments des estuaires; Zone intertidale; Littoraux; Érosion; Baie de Somme; Coast; Sedimentology; Silting prevention; Estuarine sediments; Intertidal zone; Tides.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00676/78853/81154.pdf

The nature of aquatic landscapes in the Miocene of western Amazonia: an integrated palaeontological and geochemical approach
Provedor de dados: 16
Autores: Wesselingh, F.P.; Kaandorp, R.J.G.; Vonhof, H.B.; Räsänen, M.E.; Renema, W.; Gingras, M.
The Miocene Pebas Formation from the section Santa Rosa de Pichana (Loreto, Peru) was investigated using a combination of analyses of sedimentary facies, molluscan communities and taphonomy, and stable isotopes of both entire shells and growth bands in bivalves. Three sequences, comprising a succession of transgressive, maximum flooding and regressive/prograding intervals, are documented. Molluscs are most common in the transgressive/highstand intervals and are almost absent in regressive/prograding intervals. The fauna is dominated by endemic Pebasian species, such as Pachydon and Dyris spp. The nature of the deposits as well as the availability of oxygen varied in a predictable way within each of the sequences and determined the nature of the...
Tipo: Article / Letter to the editor
Palavras-chave: Miocene; Amazonia; Palaeoecology; Sedimentology; Stable isotopes; 38.22; 42.73.
Ano: 2006
URL: http://www.repository.naturalis.nl/record/209732

Stabilisation et réhabilitation des dunes bordières de la côte nord de Mahdia (Tunisie orientale)
Provedor de dados: 20
Autores: Amrouni, Oula.
Tipo: Theses and Dissertations
Palavras-chave: Sedimentology.
Ano: 2002
URL: http://hdl.handle.net/1834/5398

Sidementological and environmental impacts of development projects along the coast of hurghada, red sea, egypt
Provedor de dados: 20
Autores: Mansour, A.M.; Mohamed, A.W.; El Dien, G.K.; Sayed, S.M.
The studies areas lay in Hurghada region include different aspects of coastal development. It represents different environmental problems and threats to the Red Sea ecosystem and geosystem. They include two tourist projects, a central marina for yachts and fishermen and a site for oil exploration and production. All sits have implemented Environmental Impact Assessment studies (EIA). Unfortunately, dredging and landfilling caused severe coast destruction and shoreline change in these areas. All sites have accurately surveyed and environmental problems cited, oceanographic parameters were measured, and 109 samples were collected from the beach and the tidal flat of four sits forming the study area. Grain size, carbonates and organic matter contents, major...
Tipo: Journal Contribution
Palavras-chave: Field Study; Environmental conditions; Sedimentology; Coastal erosion.
Ano: 2007
URL: http://hdl.handle.net/1834/1904

Impact des émissaires et canalisation sur l'environnement de la baie de Tanger ( Maroc ) : Approche géochimique
Provedor de dados: 20
Autores: Achab, M.; El hatimi, I.; El moumni, B.
Dans le but d’évaluer le degré de contamination chimique et/ou organique des sédiments superficiels le long des émissaires continentaux, des échantillons de sédiments de surface ont été prélevés et analysés le long des oueds Souani et Mghogha et au niveau de la canalisation majeure de la ville de Tanger débouchant sur la baie située sur la marge méditerranéenne marocaine. La dynamique sédimentaire dans les oueds montre exceptionnellement une évolution amont–aval granocroissante en relation avec l’activité anthropique (remblaiement des bassins versants par les matériaux de construction tels que les briques, ciments, verres, etc.). La matière organique est présente à des teneurs relativement élevées en corrélation positive avec la sédimentation fine. L’azote...
Tipo: Journal Contribution
Palavras-chave: Sedimentology; Mineralogy; Pollution; Geochemical surveys; Bay dynamics.
Ano: 2002
URL: http://hdl.handle.net/1834/199

Du modele à la nature : l'exemple de la côte Togolaise
Provedor de dados: 20
Autores: Rossi, G.; Baritse, L.; Blivi, A.B.
La côte togolaise, basse et sableuse, soumise è une violente érosion par suite d'une série d'erreurs d'aménagements, a fait l'objet en 1987-1988 d'importants travaux destin's à protéger sur 15 km la ville d'Aného et l'usine de phosphates de Kpémé, principale industrie du pays. La préparation de ces travaux, de protection, rendus indispensables par la gravité des enjeux économiques et sociaux, a nécessité des études hydrologiques et sédimentologiques très détaillées, ainsi que la construction et l'exploitation par un bureau d'étude spécialisé de deux importants modèles physique (32 x 20 m) destinés à optimiser le dispositif de protection et à déterminer l'évolution du trait de côte sur une période de 25 ans...
Tipo: Other
Palavras-chave: Coastal zone; Sedimentology; Coastal erosion; Coastal erosion; Http://aims.fao.org/aos/agrovoc/c_9949.
Ano: 1991
URL: http://hdl.handle.net/1834/1228

Estudio sedimentológico y mineralógico de la plataforma continental ecuatoriana en el tramo comprendido  entre Salinas y Ayampe
Provedor de dados: 20
Autores: Soledispa, B.; Villacres, J.
Esta investigación tiene como principal objetivo conocer como están distribuidos los sedimentos en el área, su origen, procedencia y su comportamiento en relación a los agentes de transporte y sedimentación que allí actúan.
Tipo: Journal Contribution
Palavras-chave: Sedimentology; Mineralogy; Distribution; Sediment analysis; Mineralogy; Distribution; Http://aims.fao.org/aos/agrovoc/c_4856; Http://aims.fao.org/aos/agrovoc/c_35773.
Ano: 1989
URL: http://hdl.handle.net/1834/2158

Caracterización geomorfológica y sedimentológica de la Bahía de Jaramijó, en la provincia de Manabí
Provedor de dados: 20
Autores: Soledispa, B.
En este trabajo se presentan los resultados del reconocimiento geológico de la zona de playa, zona de dunas, de los acantilados, así como fotografías de las características geomorfológicas más sobresalientes de la Bahía de Jaramijó, observadas en el año 2008. Los acantilados son de mediana a baja altura, conformados por rocas sedimentarias, principalmente de la Formación Tablazo. Hay algunos sectores donde la erosión es más fuerte, producto del socavamiento que hace el oleaje en la base de los acantilados. También se presentan los resultados de las investigaciones realizadas sobre sedimentos superficiales de fondo, desde el punto de vista de la textura y de los parámetros estadísticos. Un total de 45 muestras de sedimentos del fondo marino de la zona...
Tipo: Journal Contribution
Palavras-chave: Geomorphology; Sedimentology; Sedimentary rocks; Parameters; Cliffs.
Ano: 2012
URL: http://hdl.handle.net/1834/4720

Mineralogical and geochemical influences on sediment color of Amazon wetlands analyzed by visible spectrophotometry
Provedor de dados: 36
Autores: Guimarães,José Tasso Felix; Cohen,Marcelo Cancela Lisboa; França,Marlon Carlos; Silva,Any Kelly Terra da; Rodrigues,Suyanne Flavia Santos.
Based on sedimentological and geochemical data, this work relates spectrophotometric measurements with sediment composition and its application in palaeoecological studies of Amazon wetlands. The CIELAB values are directly related to mineralogical and chemical composition, mostly involving quartz, iron oxyhydroxides and sulfides (e.g. pyrite), and total organic carbon. Total organic carbon contents between 0.4-1%, 1-2%, 3-5% and 15-40% were related to L* (lightness) data of 27, 26-15, 7-10 and 7 or less, respectively. The CIELAB values of a deposit in Marabá, Pará, were proportional to variations in quartz and total organic carbon contents, but changes in zones of similar color, mainly in the +a* (red) and +b* (yellow) values of deposits in Calçoene, Amapá...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Sedimentology; Amazon region; Munsell color systems; Mineralogy; Chemical composition.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672013000300009

Contribution to the stratigraphy of the onshore Paraíba Basin, Brazil
Provedor de dados: 42
Autores: Rossetti,Dilce F.; Góes,Ana M.; Bezerra,Francisco H.R.; Valeriano,Márcio M.; Brito-Neves,Benjamim B.; Ochoa,Felipe L.
Several publications have contributed to improve the stratigraphy of the Paraíba Basin in northeastern Brazil. However, the characterization and distribution of sedimentary units in onshore areas of this basin are still incomplete, despite their significance for reconstructing the tectono-sedimentary evolution of the South American passive margin. This work provides new information to differentiate among lithologically similar strata, otherwise entirely unrelated in time. This approach included morphological, sedimentological and stratigraphic descriptions based on surface and sub-surface data integrated with remote sensing, optically stimulated luminescence dating, U+Th/He dating of weathered goethite, and heavy mineral analysis. Based on this study, it...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Morphology; Sedimentology; Stratigraphy; Chronology; Tectonics; Paraíba Basin.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652012000200007

Late Quaternary drainage dynamics in northern Brazil based on the study of a large paleochannel from southwestern Marajó Island
Provedor de dados: 42
Autores: Rossetti,Dilce F.; Góes,Ana M.
Marajó Island shows an abundance of paleochannels easily mapped in its eastern portion, where vegetation consists mostly of savannas. SRTM data make possible to recognize paleochannels also in western Marajó, even considering the dense forest cover. A well preserved paleodrainage network from the adjacency of the town of Breves (southwestern Marajó Island) was investigated in this work combining remote sensing and sedimentological studies. The palimpsest drainage system consists of a large meander connected to narrower tributaries. Sedimentological studies revealed mostly sharp-based, fining upward sands for the channelized features, and interbedded muds and sands for floodplain areas. The sedimentary structures and facies successions are in perfect...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Remote sensing; Sedimentology; Paleochannel; Marajó Island; Quaternary.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652008000300017