A5029506089- Geology and Paleoclimatology Research
- Marine and environmental studies
- Archaeology and ancient environmental studies
- Pleistocene-Era Hominins and Archaeology
- Isotope Analysis in Ecology
- Hydrocarbon exploration and reservoir analysis
- Methane Hydrates and Related Phenomena
- Tree-ring climate responses
- Soil and Environmental Studies
- Peatlands and Wetlands Ecology
- Geological Studies and Exploration
- Geological formations and processes
- Marine and coastal ecosystems
- Ancient and Medieval Archaeology Studies
- Coastal wetland ecosystem dynamics
- Geological and Geophysical Studies
- Maritime and Coastal Archaeology
- Geochemistry and Geologic Mapping
- Pacific and Southeast Asian Studies
- Ancient Mediterranean Archaeology and History
- Metabolomics and Mass Spectrometry Studies
- Ecology and Vegetation Dynamics Studies
- Cancer, Hypoxia, and Metabolism
- Plant Ecology and Soil Science
- Rangeland Management and Livestock Ecology
Centre National de la Recherche Scientifique
2014-2025
Laboratoire de Géologie de Lyon : Terre, Planètes et Environnement
2015-2025
Université Claude Bernard Lyon 1
2015-2025
École Normale Supérieure de Lyon
2015-2025
Collège de France
2007-2024
Université Jean Monnet
2018-2024
University of Ngaoundéré
2023
Archéorient
2021
Université de Yaoundé I
2020
Centre de Recherche et d’Enseignement de Géosciences de l’Environnement
2007-2019
We present a new set of 14 C ages obtained by accelerator mass spectrometry (AMS) on planktonic foraminifera from deep-sea core collected off the Iberian Margin (MD952042). This site, at 37°N, is distant high-latitude zones where reservoir age large and variable. Many independent proxies — alkenones, magnetic susceptibility, ice-rafted debris, stable isotopes, abundances foraminifera, pollen, dinoflagellates show abrupt changes correlative with Dansgaard-Oeschger Heinrich events last glacial...
Significance Modern human societies live in strongly altered ecosystems. However, anthropogenic environmental disturbances occurred long before the industrial revolution. About 2,600 y ago, a forest–savannah mosaic replaced dense rainforests Western Central Africa. This rainforest crisis was previously attributed either to impact of climate change or, lesser extent, expansion Bantu peoples through A 10,500-y sedimentary record from Lake Barombi, Southwest Cameroon, demonstrates that not...
ABSTRACT Aim Pollen assemblages are widely used to infer paleoenvironment features, aiming at reconstructing both past climates and biomes. However, the functional link between environmental conditions pollen is not straightforward requires thorough testing be confidently. Here, we use a trait‐based approach assess consistency of signatures plant assemblages. Location Arid Central Asia (ACA). Taxon Spermatophytes (pollen‐producing plants). Methods We whether trait values distributions...
During the Last Glacial Maximum, sea-level lowstand combined with large extent of Fennoscandian and British ice sheets led to funneling European continental runoff, resulting in largest river system that ever drained continent. Here, we show an abrupt early reactivation hydrological cycle at onset last deglaciation, leading intense discharge Channel River into Bay Biscay. This freshwater influx, probably inputs from proglacial or ice-dammed lakes, dramatically affected hydrology region, both...
[1] Sediments deposited under lacustrine and marine conditions in the Sea of Marmara hold a Late Quaternary record for water exchange between Black Mediterranean Sea. Here we report multiproxy data set based on oxygen strontium isotope results obtained from carbonate shells, major trace elements, specific organic biomarker measurements, as well micropaleontological study 14C-dated sediment core retrieved Marmara. Pronounced changes occurred δ18O 87Sr/86Sr values at fresh transition,...
Two commonly used proxies based on the distribution of glycerol dialkyl tetraethers (GDGTs) are TEX 86 (TetraEther indeX carbon atoms) paleothermometer for sea surface temperature reconstructions and BIT (Branched Isoprenoid Tetraether) index reconstructing soil organic matter input to ocean. An initial round‐robin study two sediment extracts, in which 15 laboratories participated, showed relatively consistent values (reproducibility ±3–4°C when translated temperature) but a large spread...
Continental ice sheets are a key component of the Earth’s climate system, but their internal dynamics need to be further studied. Since last deglaciation, northern Eurasian Fennoscandian Ice Sheet (FIS) has been connected Black Sea (BS) watershed, making this basin suitable location investigate former ice-sheet dynamics. Here, from core retrieved in BS, we combine use neodymium isotopes, high-resolution elemental analysis, and biomarkers trace changes sediment provenance river runoff. We...
Recently, two new proxies based on the distribution of glycerol dialkyl tetraethers (GDGTs) were proposed, i.e., TEX 86 proxy for sea surface temperature reconstructions and BIT index reconstructing soil organic matter input to ocean. In this study, fifteen laboratories participated in a round robin study sediment extracts with range values test analytical reproducibility repeatability analyzing these proxies. For repeatability, indicating intralaboratory variation, was 0.028 0.017 or ±1–2°C...
We present a new record of radiocarbon ages measured by accelerator mass spectrometry (AMS) on deep-sea core collected off the Pakistan Margin. The 14 C planktonic foraminifera Globigerinoides ruber from MD04-2876 define high and stable sedimentation rate order 50 cm/kyr over last kyr. site is distant main upwelling zone western Arabian Sea where reservoir age large may be variable. Many independent proxies based elemental analyses, mineralogy, biomarkers, isotopic proxies, foraminiferal...
This study aims at providing robust temperature reconstructions for a key oceanographic setting in the North Atlantic and understanding nature of signal recorded by two biomarkers Uk′37 TEX86, considering season depth production. To do so, high-resolution signals TEX86 are determined last 70 kyr core MD95-2042, located off Portugal. Signals present tight correlation, demonstrating dominant effect. correspond well to annual mean sea surface (SST), whereas TEXH86-derived temperatures 5.6°C...
Abstract. Holocene eastern Mediterranean Sea sediments contain an organic-rich sapropel S1 layer that was formed in oxygen-depleted waters. The spatial distribution of this revealed during deposition, deep waters were anoxic below a depth 1800 m. However, whether boundary permanently existed from the early to mid-Holocene has not been examined yet. To answer question, multi-proxy approach applied core retrieved close m (at 1780 m). We measured bulk sediment elemental composition, stable...
Abstract The Eurasian inland propagation of temperature anomalies during glacial millennial‐scale climate variability is poorly understood, but this knowledge crucial to understanding hemisphere‐wide atmospheric teleconnection patterns and mechanisms. Based on biomarkers geochemical paleothermometers, a pronounced continental between 64,000 20,000 years ago, coinciding with the Greenland Dansgaard‐Oeschger cycles, was determined in well‐dated sediment record from formerly enclosed Black Sea....
Abstract RI‐OH′ and RI‐OH (ring index of hydroxylated tetraethers) are two novel organic paleothermometers which could either complement or replace more established paleothermometric proxies, such as U K ′ 37 (C ketone unsaturation ratio) TEX 86 (TetraEther indeX tetraethers consisting carbon atoms). Despite a few promising attempts, the potential is not fully constrained. Here we present new high‐resolution temperature records over 160‐45 ka BP (before = year 1950 CE) period using four...