Holocene climate variability deciphered from Chilika Lagoon sediments: Implication for anthropogenic activity or paleocyclones?
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Le résumé fourni par la source
• High energy event post ∼1.1 Ka is recorded in the lacustrine sediments of Chilika. • Indian summer monsoon was high during the early Holocene. • CaCO 3 content and F2 values suggest the formation of barrier spit post ∼4 Ka. • High physical weathering dominated during ∼4 Ka arid period. Coastal lagoons, acting as a link between land and sea, serve as valuable archives for past climate variations, human activities, and paleo-cyclonic events. In this study, we employ a multi-proxy approach to analyze sedimentary records and uncover climatic shifts influenced by both monsoonal and non-monsoonal factors. Our analysis incorporates sediment characteristics such as grain size, magnetic susceptibility (MS), and clay mineralogy to infer high-energy conditions within the Chilika Lagoon. Additionally, we utilize Rock-Eval pyrolysis and deconvolution of flame ionization detector (FID) signals to determine the type of organic matter (OM) present. Findings reveal that during the Early Holocene, a high sand percentage and elevated MS indicate an intensified monsoon, coinciding with a dominance of terrestrial OM. However, as monsoonal intensity declined after the Early Holocene, marine OM became more prevalent, likely linked to the formation of an estuary around ∼7.7 Ka. Despite a weakening monsoon around ∼4 Ka, MS values remained high, possibly due to increased aeolian input, which transported titanomagnetite, contributing to elevated MS in the sediment record. After ∼4 Ka, the sedimentary record indicates a greater influx of terrestrial OM, likely due to the formation of a barrier spit that limited marine influence. From this period onward, monsoonal intensity gradually increased, peaking around ∼1.1 Ka, coinciding with the Medieval Warm Period. Following ∼1.1 Ka, sedimentation rates rose, accompanied by low magnetic susceptibility (MS) and high sand content. This phase also shows an increase in both terrestrial and marine OM, along with higher CaCO₃ and illite concentrations, suggesting the impact of high-energy events, possibly cyclones. The intensification of cyclonic activity after ∼1.1 Ka may be associated with a weakening of El Niño–Southern Oscillation (ENSO) intensity during this period.
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Le contrôle bibliographique ouvert
DOI retrouvé dans Crossref DOI retrouvé ; titre concordant.
- Titre Crossref
- Holocene climate variability deciphered from Chilika Lagoon sediments: Implication for anthropogenic activity or paleocyclones?
- Date Crossref
- 01/08/2025
- Éditeur
- Elsevier BV
- Type
- journal-article
Ce recoupement confirme des métadonnées liées au DOI. Il ne confirme ni la méthode ni les conclusions de l’étude, et il ne compte pas comme une seconde source scientifique indépendante.
Où se fait cette recherche
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National Geophysical Research Institute pays non établi dans la noticeStructure de recherche
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Academy of Scientific and Innovative Research pays non établi dans la noticeUniversité ou école supérieure
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National Sun Yat-sen University Department of Oceanography pays non établi dans la noticeUniversité ou école supérieure
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Indian Institute of Technology Kanpur Department of Earth Sciences pays non établi dans la noticeUniversité ou école supérieure
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University of Delhi Department of Geology pays non établi dans la noticeUniversité ou école supérieure
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Universidade de Brasília pays non établi dans la noticeUniversité ou école supérieure
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Inter-University Accelerator Centre pays non établi dans la noticeStructure de recherche
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University of Brasilia Department of Civil and Environmental Engineering pays non établi dans la noticeUniversité ou école supérieure
National Geophysical Research Institute, Academy of Scientific and Innovative Research et Department of Oceanography — National Sun Yat-sen University, avec 5 autres affiliations.
Une affiliation ne permet pas de déduire la nationalité d’un auteur.