Cerium Anomalies and Paleoredox

Cerium Anomalies and Paleoredox

Author: Rosalie Tostevin

Publisher: Cambridge University Press

Published: 2021-02-25

Total Pages: 75

ISBN-13: 9781108810739

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Ce anomalies track changes in oxygen availability due to the anomalous redox-sensitivity of Ce compared with the other rare earth elements. The proxy systematics have been calibrated experimentally as well as in modern anoxic water bodies. Ce anomalies are unique because they track intermediate manganous conditions, rather than fully anoxic conditions. In addition, they are sensitive to local-regional redox conditions, and can be analysed in chemical sediments such as carbonate rocks. This makes them especially useful as a tool to track local oxygen distribution in shallow shelf environments, where biodiversity is highest. This review focusses on the systematics of the Ce anomaly proxy, the preservation and extraction of the signal in sedimentary rocks, and the potential applications of the proxy.


Book Synopsis Cerium Anomalies and Paleoredox by : Rosalie Tostevin

Download or read book Cerium Anomalies and Paleoredox written by Rosalie Tostevin and published by Cambridge University Press. This book was released on 2021-02-25 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ce anomalies track changes in oxygen availability due to the anomalous redox-sensitivity of Ce compared with the other rare earth elements. The proxy systematics have been calibrated experimentally as well as in modern anoxic water bodies. Ce anomalies are unique because they track intermediate manganous conditions, rather than fully anoxic conditions. In addition, they are sensitive to local-regional redox conditions, and can be analysed in chemical sediments such as carbonate rocks. This makes them especially useful as a tool to track local oxygen distribution in shallow shelf environments, where biodiversity is highest. This review focusses on the systematics of the Ce anomaly proxy, the preservation and extraction of the signal in sedimentary rocks, and the potential applications of the proxy.

Cerium Anomalies and Paleoredox

Cerium Anomalies and Paleoredox

Author: Rosalie Tostevin

Publisher: Cambridge University Press

Published: 2021-02-25

Total Pages: 46

ISBN-13: 1108847579

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Ce anomalies track changes in oxygen availability due to the anomalous redox-sensitivity of Ce compared with the other rare earth elements. The proxy systematics have been calibrated experimentally as well as in modern anoxic water bodies. Ce anomalies are unique because they track intermediate manganous conditions, rather than fully anoxic conditions. In addition, they are sensitive to local–regional redox conditions, and can be analysed in chemical sediments such as carbonate rocks. This makes them especially useful as a tool to track local oxygen distribution in shallow shelf environments, where biodiversity is highest. This review focusses on the systematics of the Ce anomaly proxy, the preservation and extraction of the signal in sedimentary rocks, and the potential applications of the proxy.


Book Synopsis Cerium Anomalies and Paleoredox by : Rosalie Tostevin

Download or read book Cerium Anomalies and Paleoredox written by Rosalie Tostevin and published by Cambridge University Press. This book was released on 2021-02-25 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ce anomalies track changes in oxygen availability due to the anomalous redox-sensitivity of Ce compared with the other rare earth elements. The proxy systematics have been calibrated experimentally as well as in modern anoxic water bodies. Ce anomalies are unique because they track intermediate manganous conditions, rather than fully anoxic conditions. In addition, they are sensitive to local–regional redox conditions, and can be analysed in chemical sediments such as carbonate rocks. This makes them especially useful as a tool to track local oxygen distribution in shallow shelf environments, where biodiversity is highest. This review focusses on the systematics of the Ce anomaly proxy, the preservation and extraction of the signal in sedimentary rocks, and the potential applications of the proxy.

Molybdenum as a Paleoredox Proxy

Molybdenum as a Paleoredox Proxy

Author: Stephan R. Hlohowskyj

Publisher: Cambridge University Press

Published: 2021-09-09

Total Pages: 57

ISBN-13: 1009002260

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Molybdenum (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. In this Element, we propose a refinement of Mo geochemistry within aquatic systems, ancient rocks, and modern sediments through molecular geochemistry (systematically combining concentration, isotope ratio, elemental mapping, and speciation analyses). Specifically, to intermediate sulfide concentrations governing Mo behavior below the 'switch-point' and dominant sequestration pathways in low oxygen conditions. The aim of this work is to 1) aid and improve the breadth of Mo paleoproxy interpretations by considering Mo speciation and 2) address outstanding research gaps concerning Mo systematics (cycling, partitioning, sequestration, etc.). The Mo paleoproxy has potential to solve ever complex research questions. By using molecular geochemical recommendations, improved Mo paleoproxy interpretations and reconstruction can be achieved.


Book Synopsis Molybdenum as a Paleoredox Proxy by : Stephan R. Hlohowskyj

Download or read book Molybdenum as a Paleoredox Proxy written by Stephan R. Hlohowskyj and published by Cambridge University Press. This book was released on 2021-09-09 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molybdenum (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. In this Element, we propose a refinement of Mo geochemistry within aquatic systems, ancient rocks, and modern sediments through molecular geochemistry (systematically combining concentration, isotope ratio, elemental mapping, and speciation analyses). Specifically, to intermediate sulfide concentrations governing Mo behavior below the 'switch-point' and dominant sequestration pathways in low oxygen conditions. The aim of this work is to 1) aid and improve the breadth of Mo paleoproxy interpretations by considering Mo speciation and 2) address outstanding research gaps concerning Mo systematics (cycling, partitioning, sequestration, etc.). The Mo paleoproxy has potential to solve ever complex research questions. By using molecular geochemical recommendations, improved Mo paleoproxy interpretations and reconstruction can be achieved.

Trace Elements in Waterlogged Soils and Sediments

Trace Elements in Waterlogged Soils and Sediments

Author: Jörg Rinklebe

Publisher: CRC Press

Published: 2016-08-19

Total Pages: 419

ISBN-13: 1482240521

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Many wetlands around the world act as sinks for pollutants, in particular for trace elements. In comparison to terrestrial environments, wetlands are still far less studied. A collaborative effort among world experts, this book brings the current knowledge concerning trace elements in temporary waterlogged soils and sediments together. It discusses factors controlling the dynamics and release kinetics of trace elements and their underlying biogeochemical processes. It also discusses current technologies for remediating sites contaminated with trace metals, and the role of bioavailability in risk assessment and regulatory decision making. This book is intended for professionals around the world in disciplines related to contaminant bioavailability in aquatic organisms, contaminant fate and transport, remediation technologies, and risk assessment of aquatic and wetland ecosystems.


Book Synopsis Trace Elements in Waterlogged Soils and Sediments by : Jörg Rinklebe

Download or read book Trace Elements in Waterlogged Soils and Sediments written by Jörg Rinklebe and published by CRC Press. This book was released on 2016-08-19 with total page 419 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many wetlands around the world act as sinks for pollutants, in particular for trace elements. In comparison to terrestrial environments, wetlands are still far less studied. A collaborative effort among world experts, this book brings the current knowledge concerning trace elements in temporary waterlogged soils and sediments together. It discusses factors controlling the dynamics and release kinetics of trace elements and their underlying biogeochemical processes. It also discusses current technologies for remediating sites contaminated with trace metals, and the role of bioavailability in risk assessment and regulatory decision making. This book is intended for professionals around the world in disciplines related to contaminant bioavailability in aquatic organisms, contaminant fate and transport, remediation technologies, and risk assessment of aquatic and wetland ecosystems.

High Cerium Anomalies in Zircon from Intrusions Associated with Porphyry Copper Mineralization in the Gibraltar Deposit, South-central British Columbia

High Cerium Anomalies in Zircon from Intrusions Associated with Porphyry Copper Mineralization in the Gibraltar Deposit, South-central British Columbia

Author: C. H. Kobylinski

Publisher:

Published: 2018

Total Pages: 19

ISBN-13:

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Book Synopsis High Cerium Anomalies in Zircon from Intrusions Associated with Porphyry Copper Mineralization in the Gibraltar Deposit, South-central British Columbia by : C. H. Kobylinski

Download or read book High Cerium Anomalies in Zircon from Intrusions Associated with Porphyry Copper Mineralization in the Gibraltar Deposit, South-central British Columbia written by C. H. Kobylinski and published by . This book was released on 2018 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Magnesium Isotopes

Magnesium Isotopes

Author: Edward T. Tipper

Publisher: Cambridge University Press

Published: 2022-03-03

Total Pages: 34

ISBN-13: 1108998542

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Magnesium is a major constituent in silicate and carbonate minerals, the hydrosphere and the biosphere. Magnesium is constantly cycled between these reservoirs. Since each of the major planetary reservoirs of magnesium have different magnesium isotope ratios, there is scope to use magnesium isotope ratios to trace 1) the processes that cycle Magnesium at a spatial scales from the entire planet to microscopic and 2) the relative fluxes between these reservoirs. This review summarises some of the key motivations, successes and challenges facing the use of magnesium isotopes to construct a budget of seawater magnesium, present and past.


Book Synopsis Magnesium Isotopes by : Edward T. Tipper

Download or read book Magnesium Isotopes written by Edward T. Tipper and published by Cambridge University Press. This book was released on 2022-03-03 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnesium is a major constituent in silicate and carbonate minerals, the hydrosphere and the biosphere. Magnesium is constantly cycled between these reservoirs. Since each of the major planetary reservoirs of magnesium have different magnesium isotope ratios, there is scope to use magnesium isotope ratios to trace 1) the processes that cycle Magnesium at a spatial scales from the entire planet to microscopic and 2) the relative fluxes between these reservoirs. This review summarises some of the key motivations, successes and challenges facing the use of magnesium isotopes to construct a budget of seawater magnesium, present and past.

Local and Global Controls on Carbon Isotope Chemostratigraphy

Local and Global Controls on Carbon Isotope Chemostratigraphy

Author: Anne-Sofie Ahm

Publisher: Cambridge University Press

Published: 2022-03-31

Total Pages: 48

ISBN-13: 100903362X

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Over million-year timescales, the geologic cycling of carbon controls long-term climate and the oxidation of Earth's surface. Inferences about the carbon cycle can be made from time series of carbon isotopic ratios measured from sedimentary rocks. The foundational assumption for carbon isotope chemostratigraphy is that carbon isotope values reflect dissolved inorganic carbon in a well-mixed ocean in equilibrium with the atmosphere. However, when applied to shallow-water platform environments, where most ancient carbonates preserved in the geological record formed, recent research has documented the importance of considering both local variability in surface water chemistry and diagenesis. These findings demonstrate that carbon isotope chemostratigraphy of platform carbonate rarely represent the average carbonate sink or directly records changes in the composition of global seawater. Understanding what causes local variability in shallow-water settings, and what this variability might reveal about global boundary conditions, are vital questions for the next generation of carbon isotope chemostratigraphers.


Book Synopsis Local and Global Controls on Carbon Isotope Chemostratigraphy by : Anne-Sofie Ahm

Download or read book Local and Global Controls on Carbon Isotope Chemostratigraphy written by Anne-Sofie Ahm and published by Cambridge University Press. This book was released on 2022-03-31 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over million-year timescales, the geologic cycling of carbon controls long-term climate and the oxidation of Earth's surface. Inferences about the carbon cycle can be made from time series of carbon isotopic ratios measured from sedimentary rocks. The foundational assumption for carbon isotope chemostratigraphy is that carbon isotope values reflect dissolved inorganic carbon in a well-mixed ocean in equilibrium with the atmosphere. However, when applied to shallow-water platform environments, where most ancient carbonates preserved in the geological record formed, recent research has documented the importance of considering both local variability in surface water chemistry and diagenesis. These findings demonstrate that carbon isotope chemostratigraphy of platform carbonate rarely represent the average carbonate sink or directly records changes in the composition of global seawater. Understanding what causes local variability in shallow-water settings, and what this variability might reveal about global boundary conditions, are vital questions for the next generation of carbon isotope chemostratigraphers.

Reconstructing Precambrian pCO2 and pO2 Using Paleosols

Reconstructing Precambrian pCO2 and pO2 Using Paleosols

Author: Nathan D. Sheldon

Publisher: Cambridge University Press

Published: 2021-03-04

Total Pages: 38

ISBN-13: 1108876811

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Paleosols formed in direct contact with the Earth's atmosphere, so they can record the composition of the atmosphere through weathering processes and products. Herein we critically review a variety of different approaches for reconstructing atmospheric O2 and CO2 over the past three billion years. Paleosols indicate relatively low CO2 over that time, requiring additional greenhouse forcing to overcome the 'faint young Sun' paradox in the Archean and Mesoproterozoic, as well as low O2 levels until the Neoproterozoic. Emerging techniques will revise the history of Earth's atmosphere further and may provide a window into atmospheric evolution on other planets.


Book Synopsis Reconstructing Precambrian pCO2 and pO2 Using Paleosols by : Nathan D. Sheldon

Download or read book Reconstructing Precambrian pCO2 and pO2 Using Paleosols written by Nathan D. Sheldon and published by Cambridge University Press. This book was released on 2021-03-04 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: Paleosols formed in direct contact with the Earth's atmosphere, so they can record the composition of the atmosphere through weathering processes and products. Herein we critically review a variety of different approaches for reconstructing atmospheric O2 and CO2 over the past three billion years. Paleosols indicate relatively low CO2 over that time, requiring additional greenhouse forcing to overcome the 'faint young Sun' paradox in the Archean and Mesoproterozoic, as well as low O2 levels until the Neoproterozoic. Emerging techniques will revise the history of Earth's atmosphere further and may provide a window into atmospheric evolution on other planets.

Emerging Patterns in Proterozoic Lipid Biomarker Records

Emerging Patterns in Proterozoic Lipid Biomarker Records

Author: Gordon D. Love

Publisher: Cambridge University Press

Published: 2021-03-25

Total Pages: 82

ISBN-13: 1108847536

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Diverse and abundant lipid biomarker assemblages have been reported from a variety of Proterozoic marine environments from the careful analysis of well-preserved rocks and oils. These molecular biosignatures have provided unique insights into the communities and the environmental conditions which characterized the Proterozoic marine biosphere. We summarize some of the major temporal patterns evident in Proterozoic lipid biomarkers found to date, whilst emphasizing the scale of local heterogeneity found within Neoproterozoic oceans from region to region, and their relationship with the evolving ecological, climatic and ocean/atmospheric redox conditions. Short commentaries on a selection of papers published from the last 15 years of biomarker literature are given. The focus here is on key studies, highlighted for further reading, which have helped to better constrain the timing of the ecological expansion of eukaryotes in Proterozoic oceans or which have impacted on our knowledge of the biological sources of Proterozoic biomarkers.


Book Synopsis Emerging Patterns in Proterozoic Lipid Biomarker Records by : Gordon D. Love

Download or read book Emerging Patterns in Proterozoic Lipid Biomarker Records written by Gordon D. Love and published by Cambridge University Press. This book was released on 2021-03-25 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diverse and abundant lipid biomarker assemblages have been reported from a variety of Proterozoic marine environments from the careful analysis of well-preserved rocks and oils. These molecular biosignatures have provided unique insights into the communities and the environmental conditions which characterized the Proterozoic marine biosphere. We summarize some of the major temporal patterns evident in Proterozoic lipid biomarkers found to date, whilst emphasizing the scale of local heterogeneity found within Neoproterozoic oceans from region to region, and their relationship with the evolving ecological, climatic and ocean/atmospheric redox conditions. Short commentaries on a selection of papers published from the last 15 years of biomarker literature are given. The focus here is on key studies, highlighted for further reading, which have helped to better constrain the timing of the ecological expansion of eukaryotes in Proterozoic oceans or which have impacted on our knowledge of the biological sources of Proterozoic biomarkers.

Large Meteorite Impacts and Planetary Evolution VI

Large Meteorite Impacts and Planetary Evolution VI

Author: Wolf Uwe Reimold

Publisher: Geological Society of America

Published: 2021-09-23

Total Pages: 644

ISBN-13: 081372550X

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"This volume contains a sizable suite of contributions dealing with regional impact records (Australia, Sweden), impact craters and impactites, early Archean impacts and geophysical characteristics of impact structures, shock metamorphic investigations, post-impact hydrothermalism, and structural geology and morphometry of impact structures - on Earth and Mars"--


Book Synopsis Large Meteorite Impacts and Planetary Evolution VI by : Wolf Uwe Reimold

Download or read book Large Meteorite Impacts and Planetary Evolution VI written by Wolf Uwe Reimold and published by Geological Society of America. This book was released on 2021-09-23 with total page 644 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This volume contains a sizable suite of contributions dealing with regional impact records (Australia, Sweden), impact craters and impactites, early Archean impacts and geophysical characteristics of impact structures, shock metamorphic investigations, post-impact hydrothermalism, and structural geology and morphometry of impact structures - on Earth and Mars"--