Isotopes in the Estuary: Conception and Application of Stable and Radioactive Carbon
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An Introduction to Isotopic Calculations John M
An Introduction to Isotopic Calculations John M. Hayes ([email protected]) Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA, 30 September 2004 Abstract. These notes provide an introduction to: termed isotope effects. As a result of such effects, the • Methods for the expression of isotopic abundances, natural abundances of the stable isotopes of practically • Isotopic mass balances, and all elements involved in low-temperature geochemical • Isotope effects and their consequences in open and (< 200°C) and biological processes are not precisely con- closed systems. stant. Taking carbon as an example, the range of interest is roughly 0.00998 ≤ 13F ≤ 0.01121. Within that range, Notation. Absolute abundances of isotopes are com- differences as small as 0.00001 can provide information monly reported in terms of atom percent. For example, about the source of the carbon and about processes in 13 13 12 13 atom percent C = [ C/( C + C)]100 (1) which the carbon has participated. A closely related term is the fractional abundance The delta notation. Because the interesting isotopic 13 13 fractional abundance of C ≡ F differences between natural samples usually occur at and 13F = 13C/(12C + 13C) (2) beyond the third significant figure of the isotope ratio, it has become conventional to express isotopic abundances These variables deserve attention because they provide using a differential notation. To provide a concrete the only basis for perfectly accurate mass balances. example, it is far easier to say – and to remember – that Isotope ratios are also measures of the absolute abun- the isotope ratios of samples A and B differ by one part dance of isotopes; they are usually arranged so that the per thousand than to say that sample A has 0.3663 %15N more abundant isotope appears in the denominator and sample B has 0.3659 %15N. -
THE NATURAL RADIOACTIVITY of the BIOSPHERE (Prirodnaya Radioaktivnost' Iosfery)
XA04N2887 INIS-XA-N--259 L.A. Pertsov TRANSLATED FROM RUSSIAN Published for the U.S. Atomic Energy Commission and the National Science Foundation, Washington, D.C. by the Israel Program for Scientific Translations L. A. PERTSOV THE NATURAL RADIOACTIVITY OF THE BIOSPHERE (Prirodnaya Radioaktivnost' iosfery) Atomizdat NMoskva 1964 Translated from Russian Israel Program for Scientific Translations Jerusalem 1967 18 02 AEC-tr- 6714 Published Pursuant to an Agreement with THE U. S. ATOMIC ENERGY COMMISSION and THE NATIONAL SCIENCE FOUNDATION, WASHINGTON, D. C. Copyright (D 1967 Israel Program for scientific Translations Ltd. IPST Cat. No. 1802 Translated and Edited by IPST Staff Printed in Jerusalem by S. Monison Available from the U.S. DEPARTMENT OF COMMERCE Clearinghouse for Federal Scientific and Technical Information Springfield, Va. 22151 VI/ Table of Contents Introduction .1..................... Bibliography ...................................... 5 Chapter 1. GENESIS OF THE NATURAL RADIOACTIVITY OF THE BIOSPHERE ......................... 6 § Some historical problems...................... 6 § 2. Formation of natural radioactive isotopes of the earth ..... 7 §3. Radioactive isotope creation by cosmic radiation. ....... 11 §4. Distribution of radioactive isotopes in the earth ........ 12 § 5. The spread of radioactive isotopes over the earth's surface. ................................. 16 § 6. The cycle of natural radioactive isotopes in the biosphere. ................................ 18 Bibliography ................ .................. 22 Chapter 2. PHYSICAL AND BIOCHEMICAL PROPERTIES OF NATURAL RADIOACTIVE ISOTOPES. ........... 24 § 1. The contribution of individual radioactive isotopes to the total radioactivity of the biosphere. ............... 24 § 2. Properties of radioactive isotopes not belonging to radio- active families . ............ I............ 27 § 3. Properties of radioactive isotopes of the radioactive families. ................................ 38 § 4. Properties of radioactive isotopes of rare-earth elements . -
Stable Isotopes in River Ice: Identifying Primary Over-Winter Streamflow
HYDROLOGICAL PROCESSES Hydrol. Process. 16, 873–890 (2002) DOI: 10.1002/hyp.366 Stable isotopes in river ice: identifying primary over-winter streamflow signals and their hydrological significance J. J. Gibson1* and T. D. Prowse2 1 Department of Earth Sciences, University of Waterloo, Waterloo, Ont. N2L 3G1, Canada 2 National Water Research Institute, 11 Innovation Blvd., Saskatoon, Sask. S7N 3H5, Canada Abstract: The process of isotopic fractionation during freezing in the riverine environment is discussed with reference to a multi-year isotope sampling survey conducted in the Liard–Mackenzie River Basins, northwestern Canada. Systematic isotopic patterns are evident in cores of congelation ice (black ice) obtained from rivers and from numerous tributaries that are recognized as primary streamflow signals but with isotope offsets close to the equilibrium ice–water fractionation. The results, including comparisons with the isotopic composition of fall and spring streamflow measured directly in water samples, suggest that isotopic shifts during ice-on occur due to gradual changes in the fraction of flow derived from groundwater, surface water and precipitation sources during the fall to winter recession. Low flow isotopic signatures during ice-on suggest a predominantly groundwater-fed regime during late winter, whereas low flow isotopic signatures during ice-off reflect a mixed groundwater-, surface water- and precipitation-fed regime during late fall. Copyright 2002 John Wiley & Sons, Ltd. KEY WORDS river ice; streamflow; stable isotopes; oxygen-18; deuterium; hydrograph separation; fractionation INTRODUCTION River, lake and sea ice covers are a valuable archive of changing climate, and specifically hydroclimatic conditions occurring through the winter (Ferrick and Prowse, 2000). -
Chemical and Isotropic Tracers of Natural Gas and Formation Waters in Fractured Shales
Chemical and isotopic tracers of natural gas and formation waters in Note: this document may contain some elements that are not fully fractured shales accessible to users with disabilities. If you need assistance accessing any information in this document, please contact [email protected]. Jennifer McIntosh, Melissa Schlegel, Brittney Bates Department of Hydrology & Water Resources University of Arizona, Tucson AZ EPA Technical Workshop Feb 24-25, 2011 Outline of Presentation 1)) What is the chemical and isotoppgic signature of formation waters and natural gas in fractured shales? 2) How does it compare with shallow drift aquifers, coalbeds, and other deep geologic formations? Illinois Basin-Case Study - 3 organic-rich formations: glacial drift, Penn. coal, & Dev. fractured shale - organicorganic-rich Ordov. ShaleShale, not part ooff this study m 500 20 km Schlegel et al. (in press, 2011, Geochimica et Cosmochimica Acta) Illinois Basin-Case Study - microbial methane in all 3 units - thermogenic methane in shale and coal m 500 20 km Schlegel et al. (in press, 2011, Geochimica et Cosmochimica Acta) Illinois Basin - water & gas samples Shallow aquifers Penn. Coals Dev. Shale Limestone aquifers 9New data (white symbols): Schlegel et al. (in press) 9Previous data (black symbols): McIntosh et al., 2002; Strąpoć et al., 2007, 2008a,b; Coleman et al, 1988 Fingerprint of natural gases 1000000 Shallow Aquifers 100000 High C1/C2, no C3 Coals 10000 1000 Shale 100 10 Shallow aquifers Penn. Coals Dev. Shale Thermogenic gas 1 -80 -75 -70 -65 -60 -55 -50 -45 -40 13 δ CCH4 (ä PDB) 13 9In general, 3 organic-rich units have different gas compositions (C1/C2+C3) and δ C-CH4 values. -
Environmental Isotope Hydrology Environmental Isotope Hydrology Is a Relatively New Field of Investigation Based on Isotopic Variations Observed in Natural Waters
Environmental Isotope Hydrology Environmental isotope hydrology is a relatively new field of investigation based on isotopic variations observed in natural waters. These isotopic characteristics have been established over a broad space and time scale. They cannot be controlled by man, but can be observed and interpreted to gain valuable regional information on the origin, turnover and transit time of water in the system which often cannot be obtained by other techniques. The cost of such investigations is usually relatively small in comparison with the cost of classical hydrological studies. The main environmental isotopes of hydrological interest are the stable isotopes deuterium (hydrogen-2), carbon-13, oxygen-18, and the radioactive isotopes tritium (hydrogen-3) and carbon-14. Isotopes of hydrogen and oxygen are ideal geochemical tracers of water because their concentrations are usually not subject to change by interaction with the aquifer material. On the other hand, carbon compounds in groundwater may interact with the aquifer material, complicating the interpretation of carbon-14 data. A few other environmental isotopes such as 32Si and 2381//234 U have been proposed recently for hydrological purposes but their use has been quite limited until now and they will not be discussed here. Stable Isotopes of Hydrogen and Oxygen in the Hydrological Cycle The variations of the isotopic ratios D/H and 18O/16O in water samples are expressed in terms of per mille deviation (6%o) from the isotope ratios of mean ocean water, which constitutes the reference standard SMOW: 5%o= (^ RSMOW The isotope ratio, R, is measured using a special mass spectrometer. -
F:\Forensic Geology\Ice Man Isotopes.Wpd
NAME 89.215 - FORENSIC GEOLOGY DEMISE OF THE ICE MAN - ISOTOPIC EVIDENCE I. Introduction Stable and radiogenic isotopic data have been used in a variety of fields to answer a wide range of scientific questions. The nucleus of an atom consists of protons (+1 charge) and neutrons (0 charge), two types of particles that have essentially the same atomic mass. The number of protons in a nucleus determines the element. For example, a nucleus with 1 proton is a hydrogen nucleus, a nucleus with 2 protons is a helium nucleus. Isotopes of an element contain the same number of protons but different numbers of neutrons. For example, there are three isotopes of hydrogen: (1) ordinary hydrogen which contains one proton and no neutrons and has an atomic mass of one; (2) deuterium which contains one proton and one neutron and has an atomic mass of two; and (3) tritium which contains one proton and two neutrons and has an atomic mass of three. The convention used to show the numbers of types of particles in a nucleus is to place the number of protons (called the atomic number) at the bottom left of the element symbol and the number of protons plus neutrons (called the atomic mass) at the upper left of the element symbol. For example, the tritium isotope is 3 shown as 1H . II. Stable isotopes Stable isotopes are not radioactive, they do not spontaneously breakdown to other atoms. In a previous exercise you used radioactive carbon to determine when the Ice Man was killed. There are three isotopes of carbon: (1) carbon 12 which contains 6 protons and 6 neutrons giving an atomic mass of 12; (2) carbon 13 which contains 6 protons and 7 neutrons giving an atomic mass of 13; and (3) carbon 14 which contains 6 protons and 8 neutrons giving an atomic mass of 14. -
Environmental Isotopes in Hydrogeology
Environmental Isotopes in Hydrogeology IanD. Clark and Peter Fritz www.science.uottawa.ca/~eih CRC Press Taylor & Francis Group Boca Raton London New York CRC Press is an imprint of the Taylor & Francis Group, an inform a business Library of Congress Cataloging-in-Publication Data Clark, Ian D. (Ian Douglas), 1954- Environmental Isotopes in Hydrogeology / Ian D, Clark and Peter Fritz p. cm. Includes bibliographical references and index. ISBN 1-56670-249-6 (alk. paper) 1. Radioactive tracers in hydrogeology. I. Fritz, P. (Peter), 1937- II. Title. GB1001.72.R34C57 551.49'028—dc21 97-21889 CIP This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission, and sources are indicated. A wide variety of references are listed. Reasonable efforts have been made to publish reliable data and information, but the author and the publisher cannot assume responsibility for the validity of all materials or for the consequences of their use. Neither this book nor any part may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, microfilming, and recording, or by any information storage or retrieval system, without prior permission in writing from the publisher. The consent of CRC Press LLC does not extend to copying for general distribution, for promotion, for creating new works, or for resale. Specific permission must be obtained in writing from CRC Press LLC for such copying. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation, without intent to infringe. -
Mass Fraction and the Isotopic Anomalies of Xenon and Krypton in Ordinary Chondrites
Scholars' Mine Masters Theses Student Theses and Dissertations 1971 Mass fraction and the isotopic anomalies of xenon and krypton in ordinary chondrites Edward W. Hennecke Follow this and additional works at: https://scholarsmine.mst.edu/masters_theses Part of the Chemistry Commons Department: Recommended Citation Hennecke, Edward W., "Mass fraction and the isotopic anomalies of xenon and krypton in ordinary chondrites" (1971). Masters Theses. 5453. https://scholarsmine.mst.edu/masters_theses/5453 This thesis is brought to you by Scholars' Mine, a service of the Missouri S&T Library and Learning Resources. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact [email protected]. MASS FRACTIONATION AND THE ISOTOPIC ANOMALIES OF XENON AND KRYPTON IN ORDINARY CHONDRITES BY EDWARD WILLIAM HENNECKE, 1945- A THESIS Presented to the Faculty of the Graduate School of the UNIVERSITY OF MISSOURI-ROLLA In Partial Fulfillment of the Requirements for the Degree MASTER OF SCIENCE IN CHEMISTRY 1971 T2572 51 pages by Approved ~ (!.{ 1.94250 ii ABSTRACT The abundance and isotopic composition of all noble gases are reported in the Wellman chondrite, and the abundance and isotopic composition of xenon and krypton are reported in the gases released by stepwise heating of the Tell and Scurry chondrites. Major changes in the isotopic composition of xenon result from the presence of radio genic Xel29 and from isotopic mass fractionation. The isotopic com position of trapped krypton in the different temperature fractions of the Tell and Scurry chondrites also shows the effect of isotopic fractiona tion, and there is a covariance in the isotopic composition of xenon with krypton in the manner expected from mass dependent fractiona tion. -
Temperature Signals of Ice Core and Speleothem Isotopic Records From
Earth and Planetary Science Letters 554 (2021) 116665 Contents lists available at ScienceDirect Earth and Planetary Science Letters www.elsevier.com/locate/epsl Temperature signals of ice core and speleothem isotopic records from 18 Asian monsoon region as indicated by precipitation δ O ∗ Wusheng Yu a,b, , Tandong Yao a,b, Lonnie G. Thompson c, Jean Jouzel d, Huabiao Zhao a,b, Baiqing Xu a,b, Zhaowei Jing a, Ninglian Wang e, Guangjian Wu a,b, Yaoming Ma a,b, Jing Gao a,b, Xiaoxin Yang a,b, Jingyi Zhang a, Dongmei Qu a a Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China b CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China c Byrd Polar and Climate Research Center, The Ohio State University, Columbus, OH 43210, USA d Laboratoire des Sciences du Climat et de l’Environnement - IPSL, UMR 8212, CEA-CNRS-UVSQ, Gif sur Yvette, France e College of Urban and Environmental Sciences, Northwest University, Xi’an 710127, China a r t i c l e i n f o a b s t r a c t Article history: Ice cores and speleothem δ18O records from Asia have been widely used as a proxy to reconstruct Received 21 November 2019 paleoclimate changes. However, whether those δ18O records are a proxy of temperature or monsoon Received in revised form 15 October 2020 intensity has remained a great controversy. Generally, ice core δ18O records from non-monsoon and Accepted 2 November 2020 transition regions indicate temperature, but ice core and speleothem δ18O records from monsoon regions Available online 17 November 2020 have been regarded as proxies for monsoon intensity or precipitation. -
Isotopes in Climatological Studies Environmental Isotopes Are Helping Us Understand the World's Climate by Kazimierz Rozanski and Roberto Gonfiantini
Features Isotopes in climatological studies Environmental isotopes are helping us understand the world's climate by Kazimierz Rozanski and Roberto Gonfiantini X he fundamental motivation for the recent explosion radiation, which otherwise would escape into space. of interest in climate studies is the growing scientific Carbon dioxide and methane are the most important concern that rapidly expanding human impact on the greenhouse gases, the concentration of which in the air global ecosystem may significantly alter the world's has been increasing since the middle of last century, climate in the near future. The major source for this con- mQiniw K»nr tint nnhf Hii£» tr\ the* nmwrinn /»ftncnrnn_ cern is the observed change in the earth's atmosphere, tion of fossil fuels. (See Table 1.) probably the most vulnerable component of the entire The predictions on the onset and extent of the green- ecosphere. house effect are, however, admittedly imprecise due to Observation data clearly show that the concentration the complexity of environmental interactions, and the in air of some trace constituents such as carbon dioxide, still incomplete knowledge of global meteorological and methane, carbon monoxide, ozone, chlorofluoro-hydro- climatological mechanisms. For instance, we are still far carbons (CFCs), nitrogen and sulphur oxides, is chang- from achieving a thorough understanding of the pro- ing as a result of anthropogenic emissions. These cesses regulating the composition of the atmosphere and changes may have harmful, far-reaching consequences the feedback mechanisms that operate between the major in the near future via direct effects on the biosphere — compartments (atmosphere, hydrosphere, biosphere, including human beings—and, indirectly, via the altera- geosphere) of the global ecosystem, and determine its tion of the life-supporting conditions. -
Isotope Geochemistry of Carbonate Dissolution and Reprecipitation in Soils R
SOIL SCIENCE Vol. 122, No. I Copyright © 1976 by The Williams &Wilkin s Co. I'rintedin U.S.A. ISOTOPE GEOCHEMISTRY OF CARBONATE DISSOLUTION AND REPRECIPITATION IN SOILS W. SALOMONS' AND W. G. MOOK Laboratoryof Inorganic Chemistry'.The University of Groningen, Zernikelaan, Paddepoel,Groningen, the Netherlands, and Physics Laboratory, University of Groningen, Westersingel 34, Groningen, the Netherlands Received for publication May 21, 197/> ABSTRACT The processes of dissolution and reprecipitation of carbonates in soils developed on carbonate rocks, loess-derived soils, and marine clay soils were studied with the methods of stable isotope geochemistry. Between 10 and 50 percent of the carbonates present in the upper part of soils developed on carbonate rocks are newly formed. In loess-derived soils and in marine clay soils, up to 100 percent of the carbonates present may be newly formed. The efficiency of the dissolution-reprecipitation process varies between 10 and 30 percent. In the salt marsh investigated the dissolution is caused by the action of biogenic carbon dioxide. INTRODUCTION pies by treatment with 95 percent orthophos- Carbonates are an important constituent of phoric acid. The presence of organic matter in the soil. The processes they are subject to are most soil samples analyzed introduces an error dissolution followed by (partial) reprecipita in both the carbon and oxygen isotopic composi tion. Reprecipitation can be easily recognized tion of less than 0.37„o (Salomons 1974). when it results in macroscopic concretions. Since this small shift has no influence on our However, when the newly formed carbonates conclusions, the time-consuming step of remov are finely divided they are difficult to detect by ing the organic matter from the sample prior to conventional methods. -
Environmental Isotopes
Chapter 12 - Environmental Isotopes Introduction Stable isotopes are used to reveal the origin of Two of the fundamental things we need to know about groundwater or other components such as nutrients. groundwater are where has it come from, and how Because radioactive isotopes change their mass over long has it been underground. The most common way time, they are used as clocks to determine the residence of determining its origin and residence time below times of water underground (Rosen & White - 2001). the surface is by using natural and man-made tracers. These tracers are substances which accompany the Generally, isotope results are far more meaningful as a water molecule from the upper atmosphere through series of measurements in space or time rather than in the deepest aquifers. isolation. In other words, a single measurement is of limited value unless there are repeat measurements or Groundwater tracers include dissolved gases and observations at different locations within a catchment. isotopes of atoms associated with water. Various Their hydrological meaning is normally interpreted in methods have been applied in Marlborough over the a regional context alongside other information and in past 40 years or so to help answer these questions particular the chemistry of the groundwater. and these powerful but cost effective tools have helped unravel the mysteries of groundwater flow Stable isotope methods in Marlborough. It is not uncommon for the only Stable isotopes are conservative in nature. Once they information about groundwater to come from a well or enter groundwater they aren’t modified by natural for a newly discovered aquifer system to be its chemical processes such as reduction or oxidation.