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Trace Metals as Paleoredox and Paleoproductivity Proxies: An Update
Chemical Geology, 2006Abstract This paper is a synthesis of the use of selected trace elements as proxies for reconstruction of paleoproductivity and paleoredox conditions. Many of the trace elements considered here show variations in oxidation state and solubility as a function of the redox status of the depositional environment.
Armelle Riboulleau +2 more
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A Re-Assessment of Elemental Proxies for Paleoredox Analysis [PDF]
Chemical Geology, 2020 Abstract Paleoredox conditions are commonly evaluated based on elemental proxies but, despite their frequency of use, most of these proxies have received little comparative evaluation or assessment of their range of applicability to paleomarine systems. Here, we evaluate 21 elemental proxies, including six proxies based on the C-S-Fe-P system (TOC, S,
Thomas Algeo, Jiangsi Liu
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Molybdenum as a Paleoredox Proxy
2021Molybdenum (Mo) is a widely used trace metal for investigating redox conditions. However, unanswered questions remain that concentration and bulk isotopic analysis cannot specially answer. Improvements can be made by combining new geochemical techniques to traditional methods of Mo analysis.
Stephan R. Hlohowskyj +2 more
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The Uranium Isotope Paleoredox Proxy
2019Uranium isotopes (238U/235U) have emerged as a proxy to reconstruct the redox conditions of the Earth's oceans and atmosphere based upon the large isotopic fractionation between reduced U(IV) and oxidized U(VI). Variations in 238U/235U, particularly when recorded in carbonate sediments, can track global trends in marine oxygenation and de-oxygenation ...
Kimberly V. Lau +2 more
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International Journal of Coal Geology, 2021
Abstract In recent 30 years, Th/U ratio has been using widely in evaluating the paleoredox conditions during the depositions of source rocks. However, there are few studies on the preconditions of the use of Th/U ratio for evaluating the paleoredox conditions.
Lei Cao
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Abstract In recent 30 years, Th/U ratio has been using widely in evaluating the paleoredox conditions during the depositions of source rocks. However, there are few studies on the preconditions of the use of Th/U ratio for evaluating the paleoredox conditions.
Lei Cao
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Digestion Methods for Trace Element Measurements in Shales: Paleoredox Proxies Examined
Chemical Geology, 2012Abstract Trace elements such as U, Mo, Re, V and Ni in marine shales are commonly used to probe paleoenvironmental conditions. Trace elements may have either a detrital or seawater source, or both. The seawater contribution is often modelled from whole-rock sediment analyses.
Bernard Bingen +2 more
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The Paleoredox Context of the McArthur and Birrindudu Basins, Northern Territory, Australia
2023La c.a. 1,75 — 1,3 Ga bassin du Grand McArthur du craton du nord de l’Australie comprend plusieurs bassins sédimentaires protérozoïques dans le Territoire du Nord, en Australie. Les suc- cessions mixtes carbonates-silicylastiques bien conservées enregistrent des dépôts dans une gamme d’environnements de dépôt marins allant des milieux ...
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Paleoredox conditions of bottom water in the northern Indian Ocean since 39 ka
Palaeogeography, Palaeoclimatology, Palaeoecology, 2022Abstract Ocean circulation has undergone significant changes during the glacial and interglacial periods. The redox condition at the sediment-water interface is mainly regulated by export productivity and ventilation of abyssal water mass. The changes in the redox condition associated with bottom water circulation in the Indian Ocean are still ...
Romi Nambiar, Ravi Bhushan, Harsh Raj
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Paleoredox and pyritization of soft-bodied fossils in the Ordovician Frankfort Shale of New York
American Journal of Science, 2013Multiple beds in the Frankfort Shale (Upper Ordovician, New York State), including the original “Beecher9s Trilobite Bed,” yield fossils with pyritized soft-tissues. A bed-by-bed geochemical and sedimentological analysis was carried out to test previous models of soft-tissue pyritization by investigating environmental, depositional and diagenetic ...
Farrell, Una C. +4 more
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Paleoproductivity and paleoredox condition of the Huai Hin Lat Formation in northeastern Thailand
Journal of Earth Science, 2016The petroleum exploration has been conducted in the Khorat Plateau since 1962 and two gas fields have been discovered and commercially produced. The lacustrine facies of the Huai Hin Lat Formation is believed to be one of the main source rocks of the gas.
Boonnarong Arsairai +3 more
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