Radiocarbon Dates
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Radiocarbon Dates from Volcanic Deposits at Mount St. Helens, Washington
UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY Radiocarbon Dates from Volcanic Deposits at Mount St. Helens, Washington By Dwight R. Crandell, Donal R. Mullineaux, Meyer Rubin, Elliott Spiker, and M. L. Kelley Open-File Report 81-844 1981 This report is preliminary and has not been edited or reviewed for conformity with U.S. Geological Survey standards or nomenclature. Radiocarbon dates from volcanic deposits at Mount St. Helens, Washington by Dwight R. Crandell, Donal R. Mullineaux, Meyer Rubin, Elliott Spiker, and M. L. Kelley Stratigraphic studies of the eruptive products of Mount St. Helens volcano, supported by radiocarbon dates, were begun in the late 1950's (Crandell and others, 1962; Mullineaux and Crandell, 1962). More detailed studies were begun by Jack H. Hyde in 1968 (Hyde, 1970, 1973, 1975) and were expanded by Crandell and Mullineaux between 1970 and the present. Age determinations in the radiocarbon laboratory of the U.S. Geological Survey in Reston, Va., on organic matter incorporated in the volcanic products, permitted the volcano's eruptive events to be arranged chronologically (table 1). These radiocarbon dates have contributed immeasurably to an understanding of the volcano's history and potential hazards (Crandell and Mullineaux, 1978), and through long-range tephrochronology have also aided in the solution of other geologic problems in the Pacific Northwest such as dating the last scabland flood in eastern Washington (Mullineaux and others, 1978). Some of the 65 radiocarbon dates listed here have been published previously, but nowhere have they all been assembled in a single place. Because of widespread interest in the past history of the volcano as a result of the eruptions that began in 1980, and to make these dates readily available to future workers, we prepared this compilation of U.S. -
Meyer Rubin-A Radiocarbon Pioneer
Radiocarbon, Vol 00, Nr 00, 2021, p 1–6 DOI:10.1017/RDC.2021.65 © The Author(s), 2021. Published by Cambridge University Press for the Arizona Board of Regents on behalf of the University of Arizona MEYER RUBIN—A RADIOCARBON PIONEER G S Burr1* • Jack McGeehin2 1Department of Geosciences, National Taiwan University, Taipei, Taiwan 2Radiocarbon Laboratory (retired), U. S. Geological Survey, Reston, VA, USA Meyer Rubin (1924–2020). Photo courtesy of Harvey Belkin. MEYER RUBIN’S RADIOCARBON LEGACY Meyer Rubin (February 17, 1924–May 2, 2020) was a pioneer in the field of radiocarbon. In 1950, after serving in World War II, he began his career as a geologist at the United States Geological Survey (USGS). He joined the survey’s radiocarbon laboratory on December 1, 1953, under Hans Suess (Suess 1954a). Suess constructed an acetylene gas 14C beta- counting laboratory that extended the age limit of the Libby 14C solid graphite method by several half-lives (Suess 1954b; Flint and Rubin 1955). After Suess left, Meyer became the director of the USGS lab. In 1956 he completed his PhD degree from the University of Chicago (Rubin 1956) and pursued his radiocarbon research at the USGS with great industry. By the end of the 1950s Meyer had reported 14C results from 38 U.S. states, 26 countries around the world, the Atlantic Ocean, Antarctica, and the stratosphere (see references in Table 1). Meyer was also a seasoned field geologist, and during the 1950s alone, he collected samples from over a dozen states. Meyer published date lists to provide a record of his efforts. -
University of Texas Radiocarbon Dates I J
[RADIocARI oN, VOL. 4, 1962, P. 43-501 UNIVERSITY OF TEXAS RADIOCARBON DATES I J. J. STIPP,* E. MOTT DAVIS, JOHN E. NOAKES,* and TOM E. HOOVER Radiocarbon Dating Laboratory, Balcones Research Center, University of Texas, Austin, Texas The C14 Dating Laboratory of the University of Texas has been working on the development of two systems of counting : gas counting with methane, and liquid scintillation counting with benzene. Lack of adequate instrumentation has retarded the work on gas counting, but the liquid scintillation work, sup- ported in part by the Department of Chemistry, finally led to the successful development of a system in which the benzene counting solvent was synthesized from acetylene by pyrolysis (Tamers, Stipp, and Collier, 1961). By coincidence, while the work on liquid scintillation was going on at the University of Texas, Noakes was doing work at the A. & M. College of Texas on a low temperature catalytic method of benzene conversion for radiocarbon dating (Noakes, Isbell, and Hood, 1961; Anonymous, 1961) . We eventually learned of each other's work, and it became evident that collaboration would be of mutual benefit. The better points of the two systems were combined, the catalytic method being chosen for the benzene conversion. A preparation sys- tem was built at the University of Texas laboratory, and a Packard Tri-Garb Liquid Scintillation Spectrometer was made available at the A. & M. College of Texas and calibrated for low level C14 counting. The cooperative effort led to successful routine dating, and produced the dates reported here. The two laboratories are still working together, but each expects soon to have a complete system, and thereafter they will operate independently. -
Radiocarbon After Four Decades RADIOCARBON R.E
Radiocarbon After Four Decades RADIOCARBON R.E. Taylor A. Long R.S. Kra Editors Radiocarbon After Four Decades An Interdisciplinary Perspective With 148 Illustrations Springer Science+Business Media, LLC R.E. Thylor Austin Long Department of Anthropology Department of Geosciences Institute of Geophysics and Planetary Physics The University of Arizona University of California, Riverside Thscon, AZ 85721 USA Riverside, CA 92521-0418 USA Renee S. Kra Department of Geosciences The University of Arizona Thscon, AZ 85721 USA Library of Congress Cataloging-in-Publication Data Radiocarbon after four decades: an interdisciplinary perspective / [editors], R.E. Taylor, Austin Long, Renee S. Kra. p. cm. Includes bibliographical references and index. ISBN 978-1-4757-4251-0 ISBN 978-1-4757-4249-7 (eBook) DOI 1O.l007/978-1-4757-4249-7 1. Radiocarbon dating. I. Taylor, R. E. (Royal Ervin), 1938- II. Long, Austin. III. Kra, Renee S. QC798.D3R3 1992 546'.6815884-dc20 91-44448 Printed on acid-free paper. © 1992 Springer Science+BusinessMedia New York Originally published by Springer-Verlag New York, Inc. in 1992 Softcover reprint of the hardcover 1st edition 1992 All rights reserved. This work may not be translated or copied in whole or in part without the written per mission of the publisher,Springer Science+Bnsiness Media, LLC, except for brief excerpts in connection with reviews or scholarly analysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereaf ter developed is forbidden. The use of general descriptive names, trade names, trademarks, etc., in this publication, even if the former are not especially identified, is not to be taken as a sign that such names, as understood by the Trade Marks and Merchandise Marks Act, may accordingly be used freely by anyone. -
SOLAR SIGNALS from 14C in TREE RINGS and DETERMINING RECURRENCE INTERVALS of GREAT SUBDUCTION ZONE EARTHQUAKES in SOUTHERN ALASK
Abstracts 231 SOLAR SIGNALS FROM 14C IN TREE RINGS ELISABETTA PIERAZZO Lunar and Planetary Laboratory, The University of Arizona, Tucson, Arizona 85721 USA and SILVIA SARTORI Department of Physics, University of Padova, Padova, Italy 14C The record in wines has shown many interesting features. The strongest signal which is imprinted in it comes from the 11-year solar cycle. Another possible feature could be a frequency modulation of solar origin, also detectable, despite the limited length of the record (carrier period 11 years, modulating period 22 years). The solar signature is also present in annual tree rings, though weaker; the length of the record is short, in any case. Long tree-ring records are now available in decadal and bi-decadal sequences. However, as it is well known, conventional spectral analysis of such temporal sequences, is affected by aliasing, which is always present in equispaced sequences where a signal lies beyond the Nyquist frequency. Thus, it is difficult to clearly define the real presence of solar cycles on the scale of centuries. Alaasing can be avoided in the analysis of unequispaced time sequences. On the other hand, unequispaced sequences ask for other more sophisticated treatments, such as Bayesian analysis. A comparison is carried out between the detectability of signals of solar origin in unequispaced and equispaced sequences, when the latter contain aliased frequencies. A frequency modulation model for wines is compared with an annual sequence in tree rings, for the last 400 years. DETERMINING RECURRENCE INTERVALS OF GREAT SUBDUCTION ZONE EARTHQUAKES IN SOUTHERN ALASKA BY RADIOCARBON DATING GEORGE PLAFKER, K R LAJOIE U S Geological Survey, Menlo Park, California 94025 USA and MEYER RUBIN U S Geological Survey, Reston, Virginia 22092 USA Rupture on the eastern segment of the Aleutian arc subduction zone produced the great 1964 Alaska earthquake and caused vertical and horizontal tectonic displacements over more than 14C 140,000 km2. -
An Integrated Chemical and Stable-Isotope Model of the Origin of Midocean Ridge Hot Spring Systems
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 90, NO. B14, PAGES 12,583-12,606, DECEMBER 10, 1985 An Integrated Chemical and Stable-Isotope Model of the Origin of Midocean Ridge Hot Spring Systems TERESASUTER BOWERS 1 AND HUGH P. TAYLOR,JR. Division of Geologicaland Planetary Sciences,California Institute of Technology,Pasadena Chemical and isotopic changes accompanying seawater-basalt interaction in axial midocean ridge hydrothermal systemsare modeled with the aid of chemical equilibria and mass transfer computer programs,incorporating provision for addition and subtractionof a wide-range of reactant and product minerals, as well as cation and oxygen and hydrogen isotopic exchangeequilibria. The models involve stepwiseintroduction of fresh basalt into progressivelymodified seawater at discrete temperature inter- vals from 100ø to 350øC, with an overall water-rock ratio of about 0.5 being constrainedby an assumed •80,2 o at 350øCof +2.0 per mil (H. Craig,personal communication, 1984). This is a realisticmodel because:(1) the grade of hydrothermal metamorphism increasessharply downward in the oceanic crust; (2) the water-rock ratio is high (> 50) at low temperaturesand low (<0.5) at high temperatures;and (3) it allows for back-reaction of earlier-formed minerals during the course of reaction progress.The results closelymatch the major-elementchemistry (Von Damm et al., 1985) and isotopic compositions(Craig et al., 1980) of the hydrothermalsolutions presently emanating from ventsat 21øN on the East Pacific Rise. The calculatedsolution chemistry,for example, correctly predicts completeloss of Mg and SO,• and substantial increases in Si and Fe; however, discrepanciesexist in the predicted pH (5.5 versus 3.5 measured)and state of saturation of the solution with respectto greenschist-faciesminerals. -
Sources of Variation in the Stable Isotopic Composition of Plants*
CHAPTER 2 Sources of variation in the stable isotopic composition of plants* JOHN D. MARSHALL, J. RENÉE BROOKS, AND KATE LAJTHA Introduction The use of stable isotopes of carbon, nitrogen, oxygen, and hydrogen to study physiological processes has increased exponentially in the past three decades. When Harmon Craig (1953, 1954), a geochemist and early pioneer of natural abundance stable isotopes, fi rst measured isotopic values of plant materials, he found that plants tended to have a fairly narrow δ13C range of −25 to −35‰. In these initial surveys, he was unable to fi nd large taxonomic or environmental effects on these values. Since that time ecologists have identi- fi ed clear isotopic signatures based not only on different photosynthetic pathways, but also on ecophysiological differences, such as photosynthetic water-use effi ciency (WUE) and sources of water and nitrogen used. As large empirical databases have accumulated and our theoretical understanding of isotopic composition has improved, scientists have continued to discover mismatches between theoretical and observed values, as well as confounding effects from sources and factors not previously considered. In the best tradi- tion of science, these discoveries have led to important new insights into physiological or ecological processes, as well as new uses of stable isotopes in plant ecophysiology. This chapter reviews the most common applications of stable isotope analysis in plant ecophysiology. Carbon isotopes Photosynthetic pathways 13 Plants contain less C than the atmospheric CO2 on which they rely for photosynthesis. They are therefore “depleted” of 13C relative to the atmo- sphere. This depletion is caused by enzymatic and physical processes that discriminate against 13C in favor of 12C. -
Biosphere: How Life Alters Climate
THIS IS THE TEXT OF AN ESSAY IN THE WEB SITE “THE DISCOVERY OF GLOBAL WARMING” BY SPENCER WEART, HTTP://WWW.AIP.ORG/HISTORY/CLIMATE. AUGUST 2021. HYPERLINKS WITHIN THAT SITE ARE NOT INCLUDED IN THIS FILE. FOR AN OVERVIEW SEE THE BOOK OF THE SAME TITLE (HARVARD UNIV. PRESS, REV. ED. 2008). COPYRIGHT © 2003-2021 SPENCER WEART & AMERICAN INSTITUTE OF PHYSICS. Biosphere: How Life Alters Climate People had long speculated that the climate might be altered where forests were cut down, marshes drained or land irrigated. Scientists were skeptical. During the first half of the 20th century, they studied climate as a system of mechanical physics and mineral chemistry, churning along heedless of the planet’s thin film of living organisms. Then around 1960, evidence of a rise in carbon dioxide showed that at least one species, humanity, could indeed alter global climate. As scientists looked more deeply into how carbon moved in and out of the atmosphere, they discovered many ways that other organisms could also exert powerful influences. Forests in particular were deeply involved in the carbon cycle, and from the 1970s onward, scientists argued over just what deforestation might mean for climate. By the 1980s, it was certain that all the planet’s ecosystems were major players in the climate changes that would determine their own future. CARBON DIOXIDE AND THE BIOSPHERE (1938-1950S) - CAN PEOPLE CHANGE CLIMATE? - WHERE DOES THE CARBON GO? (1971-1980S) - METHANE (1979-1980S) - GAIA (1972-1980S) - GLOBAL WARMING FEEDBACKS “In our century the biosphere has acquired an entirely new meaning; it is being revealed as a planetary phenomenon of cosmic character.” — W.I. -
Geochemistry of Sulfate Minerals in High- and Low-Temperature Environments: a Tribute to Robert O
University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln USGS Staff -- Published Research US Geological Survey 2005 Geochemistry of Sulfate Minerals in High- and Low-Temperature Environments: A Tribute to Robert O. Rye Robert R. Seal II U.S. Geological Survey, 954 National Center, Reston, Virginia 20192, USA, [email protected] John L. Jambor Leslie Research and Consulting, 316 Rosehill Wynd, Tsawwassen, British Columbia, V4M 3L9, Canada, [email protected] Charles N. Alpers U.S. Geological Survey, 6000 J Street, Placer Hall, Sacramento, California 95819, USA, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/usgsstaffpub Part of the Earth Sciences Commons Seal, Robert R. II; Jambor, John L.; and Alpers, Charles N., "Geochemistry of Sulfate Minerals in High- and Low-Temperature Environments: A Tribute to Robert O. Rye" (2005). USGS Staff -- Published Research. 337. https://digitalcommons.unl.edu/usgsstaffpub/337 This Article is brought to you for free and open access by the US Geological Survey at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in USGS Staff -- Published Research by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Chemical Geology 215 (2005) 1–4 www.elsevier.com/locate/chemgeo Preface Geochemistry of sulfate minerals in high- and low-temperature environments: a tribute to Robert O. Rye sored by the Mineralogical Society of America and the Geochemical Society, which immediately pre- ceded the meeting (Alpers et al., 2000). The 23 papers in this special issue typify the breadth of Bob Rye’s research in this important area of geochemistry. Bob’s undergraduate degree, with a combined major in geology and mathematics, was received in 1960 from Occidental College (Los Angeles, CA). -
Isotopic Composition of Diagenetic Carbonates in Marine Miocene Formations of California and Oregon
Isotopic Composition of Diagenetic Carbonates in Marine Miocene Formations of California and Oregon GEOLOGICAL SURVEY PROFESSIONAL PAPER 614-B Isotopic Composition of Diagenetic Carbonates in Marine Miocene Formations of California and Oregon By K. J. MURATA, IRVING FRIEDMAN, and BETH M. MADSEN SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY GEOLOGICAL SURVEY PROFESSIONAL PAPER 614-B A discussion of the isotopic composition of diagenetic carbonates i?i terms of chemical processes that operate in deeply buried marine sediments UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1969 UNITED STATES DEPARTMENT OF THE INTERIOR WALTER J. HICKEL, Secretary GEOLOGICAL SURVEY William T. Pecora, Director For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 - Price 45 cents (paper cover) CONTENTS Abstract .________________________________________ Bl Oxygen isotopic composition of dolomite_____________ B13 Introduction. _______________________________________ 1 Nature of formation water and its influence on oxygen Acknowledgments. _____________________________ 2 isotopic composition of dolomite._______________ 15 Mode of occurrence of diagenetic carbonate____________ 2 Dolomite with variable light carbon and independently Factors that control carbon and oxygen isotopic composi variable oxygen.______-___-__--___-_-_-_--______. 16 tion. ____________________________________________ 4 Dolomite with variable heavy carbon and relatively con Time and circumstance of diagenesis__________________ 5 stant heavy oxygen_______________________________ -
W. M. White Geochemistry Chapter 9: Stable Isotopes
W. M. White Geochemistry Chapter 9: Stable Isotopes CHAPTER 9: STABLE ISOTOPE GEOCHEMISTRY 9.1 INTRODUCTION table isotope geochemistry is concerned with variations of the isotopic compositions of elements arising from physicochemical processes rather than nuclear processes. Fractionation* of the iso- S topes of an element might at first seem to be an oxymoron. After all, in the last chapter we saw that the value of radiogenic isotopes was that the various isotopes of an element had identical chemical properties and therefore that isotope ratios such as 87Sr/86Sr are not changed measurably by chemical processes. In this chapter we will find that this is not quite true, and that the very small differences in the chemical behavior of different isotopes of an element can provide a very large amount of useful in- formation about chemical (both geochemical and biochemical) processes. The origins of stable isotope geochemistry are closely tied to the development of modern physics in the first half of the 20th century. The discovery of the neutron in 1932 by H. Urey and the demonstra- tion of variable isotopic compositions of light elements by A. Nier in the 1930’s and 1940’s were the precursors to this development. The real history of stable isotope geochemistry begins in 1947 with the publication of Harold Urey’s paper, “The Thermodynamic Properties of Isotopic Substances”, and Bigeleisen and Mayer’s paper “Calculation of equilibrium constants for isotopic exchange reactions”. Urey not only showed why, on theoretical grounds, isotope fractionations could be expected, but also suggested that these fractionations could provide useful geological information. -
Eolss Sample Chapters
GEOPHYSICS AND GEOCHEMISTRY - Vol.I - Geochemistry: Branches, Processes, Phenomena - Scott M. McLennan GEOCHEMISTRY: BRANCHES, PROCESSES, PHENOMENA Scott M. McLennan Department of Geosciences, State University of New York at Stony Brook, USA Keywords: Chemical elements, cosmochemistry, geochemical cycles, geochronology, isotopes, meteorites, Periodic table. Contents 1. Introduction 2. Historical Foundations of Geochemistry 3. Branches of Geochemistry 4. The Data of Geochemistry 5. Cosmochemistry: Where Geochemistry Begins 6. The Periodic Table: a Geochemical Perspective 7. Isotopes, Reservoirs, and Ages 8. Geochemical Cycles 9. The future of Geochemistry Glossary Bibliography Biographical Sketch Summary Geochemistry is concerned with understanding the distribution and cycling of the chemical elements, and their isotopes, throughout nature. It is of fundamental importance to understanding the earth and planetary sciences on a variety of both theoretical and applied levels. Accordingly, geochemistry is a highly inter-disciplinary subject and addresses problems across a broad range of the sciences, such as geology, astronomy, planetary sciences, physics, chemistry, biology, material sciences, and others. The discipline has its origins in alchemy and early metallurgy but rapidly evolved into a modern science with the discovery of the chemical elements and their properties. Geochemistry, and the closely affiliated sub-discipline of cosmochemistry, is studied through a wide variety of theoretical, experimental, and analytical methods. The subject has evolved from a substantially descriptive to a highly quantitative and predictiveUNESCO discipline. For the future, geochemistry– EOLSS will continue to contribute to our understanding of fundamental questions regarding the origin and evolution of the earth and planets andSAMPLE increasingly will play an im portantCHAPTERS role in many of the environmental issues facing humankind.