A5080738651- Geology and Paleoclimatology Research
- Geochemistry and Elemental Analysis
- Marine Biology and Ecology Research
- Methane Hydrates and Related Phenomena
- Paleontology and Stratigraphy of Fossils
- Geological formations and processes
- Geological and Geophysical Studies
- Geochemistry and Geologic Mapping
- Hydrocarbon exploration and reservoir analysis
- Geological and Geochemical Analysis
- Geomagnetism and Paleomagnetism Studies
- Isotope Analysis in Ecology
- Marine and coastal ecosystems
- Heavy metals in environment
- Marine Bivalve and Aquaculture Studies
- Radioactive element chemistry and processing
- Ocean Acidification Effects and Responses
- Mercury impact and mitigation studies
- earthquake and tectonic studies
- Groundwater and Isotope Geochemistry
- Marine and environmental studies
- Oceanographic and Atmospheric Processes
- Microbial Community Ecology and Physiology
- Planetary Science and Exploration
- Analytical chemistry methods development
National Institute of Oceanography
2015-2024
Université de Lorraine
2019
Centre National de la Recherche Scientifique
2019
GeoRessources
2019
Council of Scientific and Industrial Research
2009-2018
Central University of Kerala
2012
Seribiotechnology Research Laboratory
2012
Okayama University
2007-2009
FH Aachen
1992
Abstract The South Asian Monson (SAM) is one of the most intense climatic elements yet its initiation and variations are not well established. Dating deposits SAM wind-driven currents in IODP cores from Maldives yields an age 12. 9 Ma indicating abrupt onset, over a short period 300 kyrs. This coincided with Indian Ocean Oxygen Minimum Zone expansion as revealed by geochemical tracers onset upwelling reflected sediment’s content particulate organic matter. A weaker ‘proto-monsoon’ existed...
International Ocean Discovery Program (IODP) Expedition 359 cored sediments from eight borehole locations in the carbonate platform of Maldives Indian Ocean. The expedition set out to unravel timing Neogene climate changes, particular evolution South Asian monsoon and fluctuations sea level. these changes are assessed by dating resultant sedimentary alterations that mark stratigraphic turning points system. first four during early middle Miocene related sea-level changes. These reliably...
ABSTRACT Geochemical studies, comprising twelve major elements and twenty-four trace elements, including the rare earth (REE), have been carried out on Concentrations normalized to average upper continental crust (UCC) show that sediments studied are depleted in Rb, K, Ba, Ta, Hf, Na, Ca enriched Cs, U, Th, REEs, Sc, Fe, Co, Cr. UCC-normalized patterns strikingly similar for all three sediment types, probably because of efficient mixing sedimentary material during weathering, transport,...
The evolution and driving mechanism of the South Asian summer monsoon (SASM) are still poorly understood. We here present a 12-Myr long SASM record by analyzing strontium neodymium isotopic composition detrital components at IODP Exp. 359 Site U1467 from northern Indian Ocean. provenance investigation demonstrates that more dust enriched in εNd northeastern Africa Arabian Peninsula was transported to study site monsoonal Shamal winds during season. A two-step weakening wind since ~12 Ma is...
Bottom sediments from thirteen transects mainly sampled at depth contours of 30, 100 and 200m along the western continental margin India, falling in two offshore sectors Dwaraka to Goa Cape Comorin were analysed for calcium carbonate, major elements silicate fraction, trace rare earth bulk carbon nitrogen isotopes organic matter understand provenance sediments, weathering patterns source areas nature matter.Major such as Si, Ti, Mg discrimination plots involving alkalies silica have shown a...
Abstract Chemical weathering and the ensuing atmospheric carbon dioxide consumption has long been considered to work on geological time periods until recently when some modelling natural records have shown that weathering-related CO 2 can change at century glacial-interglacial scale. Last glacial interglacial transition period is a best test case understand interplay between Pco -temperature-chemical pulse of rapid chemical was initiated. Here we show, from high resolution 54 ka record...
The natural carbon cycle is immensely intricate to fully understand its sources, fluxes and the processes that are responsible for their cycling in different reservoirs balances on a global scale. Anthropogenic perturbations add another dimension such complex cycle. Therefore, it necessary update by combining both anthropogenic sinks along land-sea continuum assess whether these terms currently balance or not. Here, we review export burial rates of terrestrial organic oceans issue "missing...
Rare earth element (REE) concentrations have been determined in terrigenous, siliceous (nodule barren and nodule bearing), calcareous, red clay from the Central Indian Basin. The bulk distribution of REE, particular relative cerium fractionation, these surface sediments has studied relation to bottom water conditions. REE fractionations within a single depositional environment are found be characteristic for each sediment type, with flat shale‐normalized patterns associated terrigenous...
A new 3-step sequential separation chemistry for Sr, Nd and Pb from silicate samples, which is suitable isotope analysis by MC-ICP-MS as well TIMS, has been developed. The designed to minimize the number of evaporation steps, enabling high throughput especially when employed. sample solution in 0.5 mol l-1 HNO3 after digestion with HF-HClO4, prepared trace element analysis, can be directly used chemistry. In first column using Sr resin, are collected. recovered aspirated into MC-ICP-MS....
Ferromanganese nodules grow by precipitation of metals from seawater and/or sediment pore water. The formation different genetic types depends on the composition and redox conditions water upper layers, depth, primary productivity in surface waters. Many characteristics have been used to investigate their genesis. In this paper, we compare environments using Computed Tomography, Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy, Micro Fluorescence data better understand how...