Download or read book Mass independent Sulfur Isotope Fractionation During Photochemistry of Sulfur Dioxide written by Andrew Richard Whitehill and published by . This book was released on 2015 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mass-independent sulfur isotope signatures are observed in Archean and early Paleoproterozoic sedimentary sulfate and sulfide minerals, and provide the most robust constraints on early atmospheric oxygen levels. Smaller mass-independent sulfur isotope anomalies are observed in ice cores and interpreted as a tracer of stratospheric volcanic loading. Photochemistry of sulfur dioxide (SO2) has been implicated as a possible source of the mass-independent sulfur isotope signatures in both the modern stratosphere and on the early earth. However, the mechanisms responsible for the production of mass-independent sulfur isotope fractionation remain poorly constrained. This thesis investigates the multiple sulfur isotope systematics during photochemical reactions of sulfur dioxide as a function of a variety of experimental conditions. Two absorption regions of SO2 are tested - photolysis in the 190 to 220 nm region and photoexcitation in the 250 to 350 nm region. Experimental conditions modified include temperature, SO2 pressure, bath gas pressure, and addition of reactive gases (C2 H2, 02 and CH4). Results of photochemical experiments are compared with isotope systematics predicted from isotopologue-specific absorption cross-sections to identify potential mechanisms for the production of mass-independent fractionation during photochemical reactions. Strong similarity between the isotope systematics of SO2 photolysis and ice core data suggest that SO2 photolysis is responsible for the production of mass-independent sulfur isotope effects in the modern stratosphere. In contrast, significant discrepancies between the isotope signatures from SO2 photochemistry and those in the Archean record suggest that, although SO2 photolysis was likely an important process in the Archean atmosphere, an additional reaction likely contributes to the mass-independent sulfur isotope signatures preserved in the Archean rock record.
Download or read book A Mass Independent Sulfur Isotope Effect in the Non Thermal Formation of S 2F 10 written by Swroop K. Bains-Sahota and published by . This book was released on 1988 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Exploring the Contributions of Liquid phase Sulfur Chemistry to the Mass independent Sulfur Fractionation of the Archean Rock Record written by Sebastian Hermann Kopf and published by . This book was released on 2010 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Archean sulfur mass-independent fractionation (S-MIF) has been widely recognized as one of the strongest indicators for the rise of atmospheric oxygen in the Early Proterozoic. A decade after its discovery, the wide-ranging implications of Archean sulfur MIF have been discussed extensively and despite a number of recent studies on the gas-phase chemistry of sulfur, no definite overall picture has emerged to date as to the precise origin and preservation of the Archean mass-independent sulfur signal. The interpretation of the Archean sulfur MIF as a strong constraint for atmospheric oxygen levels, however, requires a dominant atmospheric source of sulfur MIF. This study was aimed at investigating the potential contribution of the poorly explored mass-independent effects from liquid-phase sulfur chemistry and focused on sulfur isotope fractionation during liquid-phase photolytic breakdown of phenacylphenylsulfone (PPS) as a model system for initial investigation. Results confirm that MIF in this system is caused by the magnetic 33S isotope and excludes other mechanisms such as nuclear volume effects or vibronic coupling that would produce concomitant MIF in the 32S-34_3-3S triad. This provides a starting point for discussing the implications of magnetic isotope effects as a mechanism for mass-independent isotope fractionation in the chemical evolution of the sulfur cycle and suggests that liquid-phase processes such as the photolysis of PPS cannot constitute the principal source of mass-independent sulfur fractionation in the Archean.
Download or read book Mass independent Sulfur Isotopic Compositions in Atmospheric Sulfates written by Alvaro Bernd Romero and published by . This book was released on 2003 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Treatise on Geochemistry written by and published by Newnes. This book was released on 2013-10-19 with total page 14787 pages. Available in PDF, EPUB and Kindle. Book excerpt: This extensively updated new edition of the widely acclaimed Treatise on Geochemistry has increased its coverage beyond the wide range of geochemical subject areas in the first edition, with five new volumes which include: the history of the atmosphere, geochemistry of mineral deposits, archaeology and anthropology, organic geochemistry and analytical geochemistry. In addition, the original Volume 1 on "Meteorites, Comets, and Planets" was expanded into two separate volumes dealing with meteorites and planets, respectively. These additions increased the number of volumes in the Treatise from 9 to 15 with the index/appendices volume remaining as the last volume (Volume 16). Each of the original volumes was scrutinized by the appropriate volume editors, with respect to necessary revisions as well as additions and deletions. As a result, 27% were republished without major changes, 66% were revised and 126 new chapters were added. In a many-faceted field such as Geochemistry, explaining and understanding how one sub-field relates to another is key. Instructors will find the complete overviews with extensive cross-referencing useful additions to their course packs and students will benefit from the contextual organization of the subject matter Six new volumes added and 66% updated from 1st edition. The Editors of this work have taken every measure to include the many suggestions received from readers and ensure comprehensiveness of coverage and added value in this 2nd edition The esteemed Board of Volume Editors and Editors-in-Chief worked cohesively to ensure a uniform and consistent approach to the content, which is an amazing accomplishment for a 15-volume work (16 volumes including index volume)!
Download or read book Mechanisms of Sulfur Isotope Fractionation During Thermochemical Sulfate Reduction by Amino Acids written by Andrew Chorney and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The understanding of the evolution of the earth's early atmosphere has largely been based on the behavior of the multiple isotopes of sulfur. However experiments designed to mimic fractionation in both an oxygen poor atmosphere through SO2 photolysis and a presumably oxygen rich atmosphere though thermochemical sulfate reduction (TSR) have thus far been unable to confirm a mechanism capable of creating the mass independent fractionation of sulfur (MIF-S) signatures observed in Archean age rocks. This has created much controversy in how the MIF-S record is used to determine Archean environments. However large amounts of geochemical evidence suggest at least appreciable amounts of oxygen in the atmosphere and ocean at different stages through the Archean. This has motivated us to further explore TSR as a source of MIF-S through a rigorous investigation of how chemical speciation, experimental conditions, time, and rate effect sulfur isotope fractionation. Our results show the importance of initial sulfur redox state and chemistry, temperature, and organic reductant type in creating characteristic mass dependent and independent fractionations. Including previous TSR results (Watanabe et. al., 2009 and Oduro et. al., 2011) we report increased [delta]34S and [delta]36S fractionation in TSR products to 15.50[per mille symbol] and 1.5[per mille symbol] respectively and increased [delta]33S range from -.22 to 2.30[per mille symbol] in H2S largely through the use of mixtures of glycine and alanine. In sulfate we observe [delta]34S fractionation between 0.00 and 7.85[per mille symbol] and [delta]33S fractionation between -.15[per mille symbol] and 0.0[per mille symbol]. By quantifying fractionation amongst different sulfur bearing products produced during experiments and collected at experiment conclusions in addition to characterizing the effects due to various experimental conditions we are also able describe a schematic framework for the isotope effects during various steps of TSR. Fractionation from the magnetic isotope effect (MIE), the vibrational energy discontinuity effect (VEDE), first described for heterogeneous reactions by Lasaga et. al, 2008, and normal stable isotope mass dependently driven kinetic isotope effects (KIE) are utilized in this schematic to describe the experimental results. The MIE and VEDE are responsible for the MIF-S signatures observed in organic polysulfides and H2S at high temperatures. Additionally the effects of these mechanisms are greatly influenced by amino acid type, specifically in experiments that use a mixture of glycine and alanine. The VEDE and KIE are responsible for [delta]34S fractionation with the overall effect of producing sulfide depleted in 34S at lower temperatures. The interplay of these mechanisms is responsible for [delta]33S and [delta]34S trends observed in sulfides and sulfate samples. Based on this proposed schematic for sulfur isotope fractionation during TSR major trends and features in the Archean [delta]33S vs. [delta]34S and [delta]36S vs. [delta]33S record can be interpreted. Our results confirm that MIF-S signatures observed in natural samples are a product of depositional environment and possibly reflect characteristics of reactions specific to sedimentary basin conditions and early earth's tectonic regime.
Download or read book Isotope Geochemistry written by William M. White and published by John Wiley & Sons. This book was released on 2023-02-13 with total page 724 pages. Available in PDF, EPUB and Kindle. Book excerpt: ISOTOPE GEOCHEMISTRY Provides a thorough and up-to-date overview of radiogenic and stable isotope geochemistry Now in its second edition, Isotope Geochemistry presents a comprehensive introduction to radiogenic and stable isotope geochemistry. The first five chapters cover fundamentals including the physics of nuclei, radioactive decay, nucleosynthesis, geochronology, and the theory of stable isotope fractionation. The next chapter focuses on the isotope geochemistry of meteorites and their constraints on the formation of the solar system and the Earth. The subsequent three chapters cover radiogenic and stable isotope geochemistry evolution of the Earth’s mantle and crust. Three more chapters are devoted to the Earth’s surface, the exogene, including the hydrologic system, the biosphere, and climate. A new chapter in this edition focuses on the use of isotopes in paleontology and archeology. The final chapter is devoted to the isotope geochemistry of the noble gases. Illustrated in full color throughout, Isotope Geochemistry is intended primarily as a textbook for advanced undergraduate and graduate students. It is also intended as a reference for earth science professionals, reflecting the impact that isotope geochemistry has on virtually every aspect of the earth sciences, from climate change and geomorphology to geodynamics.
Download or read book Non mass Dependent Fractionation of Sulfur and Oxygen Isotopes During UV Photolysis of SO2 written by Aranh Pen and published by . This book was released on 2009 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geochemistry written by William M. White and published by John Wiley & Sons. This book was released on 2020-10-02 with total page 963 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Comprehensive Introduction to the “Geochemist Toolbox” – the Basic Principles of Modern Geochemistry In the new edition of William M. White’s Geochemistry, undergraduate and graduate students will find each of the core principles of geochemistry covered. From defining key principles and methods to examining Earth’s core composition and exploring organic chemistry and fossil fuels, this definitive edition encompasses all the information needed for a solid foundation in the earth sciences for beginners and beyond. For researchers and applied scientists, this book will act as a useful reference on fundamental theories of geochemistry, applications, and environmental sciences. The new edition includes new chapters on the geochemistry of the Earth’s surface (the “critical zone”), marine geochemistry, and applied geochemistry as it relates to environmental applications and geochemical exploration. ● A review of the fundamentals of geochemical thermodynamics and kinetics, trace element and organic geochemistry ● An introduction to radiogenic and stable isotope geochemistry and applications such as geologic time, ancient climates, and diets of prehistoric people ● Formation of the Earth and composition and origins of the core, the mantle, and the crust ● New chapters that cover soils and streams, the oceans, and geochemistry applied to the environment and mineral exploration In this foundational look at geochemistry, new learners and professionals will find the answer to the essential principles and techniques of the science behind the Earth and its environs.
Download or read book Sulfur Oxides Advances in Research and Application 2013 Edition written by and published by ScholarlyEditions. This book was released on 2013-06-21 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sulfur Oxides—Advances in Research and Application: 2013 Edition is a ScholarlyBrief™ that delivers timely, authoritative, comprehensive, and specialized information about ZZZAdditional Research in a concise format. The editors have built Sulfur Oxides—Advances in Research and Application: 2013 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about ZZZAdditional Research in this book to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Sulfur Oxides—Advances in Research and Application: 2013 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
Download or read book Volcanic Plumes written by Pasquale Sellitto and published by MDPI. This book was released on 2019-03-21 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volcanoes release plumes of gas and ash to the atmosphere during episodes of passive and explosive behavior. These ejecta have important implications for the chemistry and composition of the troposphere and stratosphere, with the capacity to alter Earth's radiation budget and climate system over a range of temporal and spatial scales. Volcanogenic sulphur dioxide reacts to form sulphate aerosols, which increase global albedo, e.g., by reducing surface temperatures, in addition to perturbing the formation processes and optical properties of clouds. Released halogen species can also deplete stratospheric and tropospheric ozone. Volcanic degassing, furthermore, played a key role in the formation of Earth’s atmosphere, and volcanic plumes can affect air quality, pose hazards to aviation and human health, as well as damage ecosystems. The chemical compositions and emission rates of volcanic plumes are also monitored via a range of direct-sampling and remote-sensing instrumentation, in order to gain insights into subterranean processes, in the respect of the magmatic bodies these volatiles exsolve from. Given the significant role these gases play in driving volcanic activity, e.g., via pressurisation, the study of volcanic plumes is proving to be an increasingly fruitful means of improving our understanding of volcanic systems, potentially in concert with observations from geophysics and contributions from fluid dynamical modelling of conduit dynamics. This Special Issue is aimed at presenting the state of the art of the multidisciplinary science concerning all aspects of volcanic plumes, of relevance to the volcanology, climatology, atmospheric science, and remote sensing communities.
Download or read book Mass Independent Isotopic Fractionation in Solid Phase written by Xianping Xu and published by . This book was released on 1998 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Using Geochemical Data written by Hugh Rollinson and published by Cambridge University Press. This book was released on 2021-05-06 with total page 359 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook is a complete rewrite, and expansion of Hugh Rollinson's highly successful 1993 book Using Geochemical Data: Evaluation, Presentation, Interpretation. Rollinson and Pease's new book covers the explosion in geochemical thinking over the past three decades, as new instruments and techniques have come online. It provides a comprehensive overview of how modern geochemical data are used in the understanding of geological and petrological processes. It covers major element, trace element, and radiogenic and stable isotope geochemistry. It explains the potential of many geochemical techniques, provides examples of their application, and emphasizes how to interpret the resulting data. Additional topics covered include the critical statistical analysis of geochemical data, current geochemical techniques, effective display of geochemical data, and the application of data in problem solving and identifying petrogenetic processes within a geological context. It will be invaluable for all graduate students, researchers, and professionals using geochemical techniques.
Download or read book Earth s Oldest Rocks written by Martin J. Van Kranendonk and published by Elsevier. This book was released on 2018-09-26 with total page 1114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Earth's Oldest Rocks, Second Edition, is the only single reference source for geological research of early Earth. This new edition is an up-to-date collection of scientific articles on all aspects of the early history of the Earth, from planetary accretion at 4.567 billion years ago (Ga), to the onset of modern-style plate tectonics at 3.2 Ga. Since the first edition was published, significant new advances have been made in our understanding of events and processes on early Earth that correspond with new advances in technology. The book includes contributions from over 100 authors, all of whom are experts in their respective fields. The research in this reference concentrates on what is directly gleaned from the existing rock record to understand how our planet formed and evolved during the planetary accretion phase, formation of the first crust, the changing dynamics of the mantle and style of tectonics, life's foothold and early development, and mineral deposits. It is an ideal resource for academics, students and the general public alike. - Advances in early Earth research since 2007 based primarily on evidence gleaned directly from the rock record - More than 50% of the chapters in this edition are new and the rest of the chapters are revised from the first edition, with more than 700 pages of new material - Comprehensive reviews of areas of ancient lithosphere from all over the world, and of crust-forming processes - New chapters on early solar system materials, composition of the ancient atmosphere-hydrosphere, and overviews of the oldest evidence of life on Earth, and modeling of early Earth tectonics
Download or read book Handbook of Environmental Isotope Geochemistry written by Mark Baskaran and published by Springer Science & Business Media. This book was released on 2011-10-13 with total page 944 pages. Available in PDF, EPUB and Kindle. Book excerpt: Applications of radioactive and stable isotopes have revolutionized our understanding of the Earth and near-earth surface processes. The utility of the isotopes are ever-increasing and our sole focus is to bring out the applications of these isotopes as tracers and chronometers to a wider audience so that they can be used as powerful tools to solve environmental problems. New developments in this field remain mostly in peer-reviewed journal articles and hence our goal is to synthesize these findings for easy reference for students, faculty, regulators in governmental and non-governmental agencies, and environmental companies. While this volume maintains its rigor in terms of its depth of knowledge and quantitative information, it contains the breadth needed for wide variety problems and applications in the environmental sciences. This volume presents all of the newer and older applications of isotopes pertaining to the environmental problems in one place that is readily accessible to readers. This book not only has the depth and rigor that is needed for academia, but it has the breadth and case studies to illustrate the utility of the isotopes in a wide variety of environments (atmosphere, oceans, lakes, rivers and streams, terrestrial environments, and sub-surface environments) and serves a large audience, from students and researchers, regulators in federal, state and local governments, and environmental companies.
Download or read book The Chemical Evolution of the Atmosphere and Oceans written by Heinrich D. Holland and published by Princeton University Press. This book was released on 1984-07-21 with total page 604 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this first full-scale attempt to reconstruct the chemical evolution of the Earth's atmosphere and oceans, Heinrich Holland assembles data from a wide spectrum of fields to trace the history of the ocean-atmosphere system. A pioneer in an increasingly important area of scholarship, he presents a comprehensive treatment of knowledge on this subject, provides an extensive bibliography, and outlines problems and approaches for further research. The first four chapters deal with the turbulent first half billion years of Earth history. The next four chapters, devoted largely to the Earth from 3.9 to 0.6 b.y.b.p., demonstrate that changes in the atmosphere and oceans during this period were not dramatic. The last chapter of the book deals with the Phanerozoic Eon; although the isotopic composition of sulfur and strontium in seawater varied greatly during this period of Earth history, the chemical composition of seawater did not.
Download or read book Handbook of Stable Isotope Analytical Techniques written by Pier A. de Groot and published by Elsevier. This book was released on 2004-10-27 with total page 1265 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Parent with price) Volume I contains subjective reviews, specialized and novel technique descriptions by guest authors. Part 1 includes contributions on purely analytical techniques and Part 2 includes matters such as development of mass spectrometers, stability of ion sources, standards and calibration, correction procedures and experimental methods to obtain isotopic fractionation factors.Volume II will be available in 2005.
