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Mohamed, A.W.. |
The grain size distribution and arameters, major and trace elements, carbonate, total phosphorus, organic carbon and total organic matter has been assessed for core sediments collected in the intertidal area of Qusier, Safaga and Hurghada harbors in July 2002. Mud is the dominant fraction in almost all samples of Qusier core and some samples of Safaga and Hurghada cores. The reason for the high mud content of all Qusier core samples and some samples of Safaga and Hurghada cores is due to the terrigenous flux of wadies, phosphate deposits, landfill and dredging in these areas. Metals concentrations in the core sediments vary between sites within a wide range for Cu, Zn, Pb, V, Ni and Cd. Concentration of metals in the sediments at the top of cores is the... |
Tipo: Journal Contribution |
Palavras-chave: Trace elements; Carbonate; Anthropogenic impacts; Remediation Environments Grain size Marine environment Marine pollution Organic matter Marine environment Organic matter Environment http://aims.fao.org/aos/agrovoc/c_4610 http://aims.fao.org/aos/agrovoc/c_5387 http://aims.fao.org/aos/agrovoc/c_2593. |
Ano: 2005 |
URL: http://hdl.handle.net/1834/1248 |
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Dekov, V.m.; Egueh, N. M.; Kamenov, G. D.; Bayon, G.; Lalonde, S.v.; Schmidt, M.; Liebetrau, V.; Munnik, F.; Fouquet, Yves; Tanimizu, M.; Awaleh, M. O.; Guirreh, I.; Le Gall, B.. |
Carbonate chimney-like deposits up to 60 m high are scattered or arranged in rows at the shores of a desiccating hypersaline and alkaline lake from a continental rift setting (Lake Abhé, Afar Rift, Djibouti). The chimneys formed sub-aqueously in the lake water body at a higher water level than observed today. Alternating calcite and low-Mg calcite + silica concentric layers compose the chimney structures. Mineralogical and geochemical investigations of the chimneys, lake water, and hot spring (hydrothermal) fluids suggest that the chimneys are a result of rapid carbonate precipitation during the mixing of hydrothermal fluids with lake water. In contrast to the hot spring fluid, lake water is enriched in HREE and possesses a pronounced positive Ce anomaly,... |
Tipo: Text |
Palavras-chave: Carbonate; Chimney; Continental rift; H-C-O-Ca-Sr-Nd-Pb-Th-U-isotopes; Hydrothermalism. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00206/31762/30172.pdf |
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Husson, L.; Pastier, A. -m.; Pedoja, K.; Elliot, M.; Paillard, D.; Authemayou, C.; Sarr, A. -c.; Schmitt, A.; Cahyarini, S. Y.. |
Global variations in reef productivity during the Quaternary depend on external parameters that may alter the global chemical balance in the oceans and atmosphere. We designed a numerical model that simulates reef growth, erosion, and sedimentation on coastlines undergoing sea level oscillations, and uplift or subsidence. We further develop a probabilistic evaluation that accounts for variable vertical ground motion, erosion, and foundation morphologies. Absolute sea level change appears primordial, as productivity must have increased by an order of magnitude since the onset of the glacial cycles, approximate to 2.6 Ma. But most important is relative sea level change, i.e., eustasy modulated by uplift or subsidence, that rejuvenates the accommodation space... |
Tipo: Text |
Palavras-chave: Coral reefs; Sea level; Carbonate; Modeling; Paleoclimate. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00638/74993/75789.pdf |
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Shiau, Liang-jian; Yu, Pai-sen; Wei, Kuo-yen; Yamamoto, Masanobu; Lee, Teh-quei; Yu, Ein-fen; Fang, Tien-hsi; Chen, Min-te. |
Variations in sea surface temperature (SST), productivity, and biogenic components such as total organic carbon (TOC), carbonate, and opal contents measured from IMAGES (International Marine Global Changes Study) core MD972142 provide information about long-term paleoceanographic changes during the past similar to 870000 years in the southeastern South China Sea (SCS). MD972142 U-37(k)-SSTs varied from 25 to 29 degrees C, paralleling the glacial to interglacial changes. MD972142 biogenic components show relatively high carbonate and opal, and low TOC contents in interglacial stages, and low carbonate and opal and high TOC contents in glacial stages, and these variations appear to be sensitive to regional terrestrial sediment input and productivity. Our... |
Tipo: Text |
Palavras-chave: Total organic carbon; Carbonate; Opal; Productivity; Sea surface temperature; South China Sea; Monsoon; IMAGES. |
Ano: 2008 |
URL: https://archimer.ifremer.fr/doc/00237/34817/33682.pdf |
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Counts, John; Jorry, Stephan; Leroux, Estelle; Miramontes, Elda; Jouet, Gwenael. |
Recently acquired data from the Iles Eparses (southwestern Indian Ocean) reveal new information about the geomorphology, depositional processes, and sedimentary deposits on the slopes of atolls and atoll-like platforms. The deposits discussed here lie on the deepwater flanks of isolated, inactive volcanos that are capped by shallow, relatively flat carbonate platforms 45–210 km2 in area. Much of the slope geomorphology is controlled by the underlying volcanic edifice. Steep (~25–35°) upper slopes consist of outcrops of volcanic basement, smooth banks, failure scarps, and channels. Sedimentary features seen in the lower slope and proximal basin (2000–3500 m deep) consist of channels, levees, lobes, and mass transport deposits (MTDs). In places, channels... |
Tipo: Text |
Palavras-chave: Atoll; Carbonate; Indian Ocean; Slope; Deepwater sediments. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00450/56136/57802.pdf |
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