Chronostratigraphy and Geochronology: a Proposed Realignment
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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. -
Building a Generic Date-Time Framework - an Experience Report Using C++ Templates
Building a Generic Date-Time Framework - An Experience Report using C++ Templates Jeff Garland President & CTO CrystalClear Software, Inc [email protected] Copyright © CrystalClear Software, Inc 2001 Revised September 7, 2001 Abstract This paper describes the experiences of the author using C++ templates to build the Generic Date Time Library (GDTL). While there are many date-time representations available for C++, the libraries are often unsuitable for domains that need high precision, long epochs, infinity, specialized calendars, or custom clock sources. The GDTL is an attempt to use generic and template programming techniques to provide a single library that meets all these demands, as well as more typical date-time programming. To build a single library, templates are used in several roles: allow user replacement of underlying date and time representations, to factor out calendar interfaces, building range and composite types, and providing interface constraint enforcement. GDTL Background I became interested in this several years ago while helping to implement date-time classes to support a satellite control system. The software performed extensive time calculations and had to manage details such as leap second tables. Some calculations, needed precision down to microseconds. Other parts of the system needed to store millions of date-times in a database (each day) with only second-level precision. So forcing microsecond resolution for all times unnecessarily bloated the size of the database. In the end, the project had more than one time library. Some good components, but a host of project realities kept us from getting everything into a single library. In addition, traditional object-oriented design techniques did not directly support the required variations. -
Do Gssps Render Dual Time-Rock/Time Classification and Nomenclature Redundant?
Do GSSPs render dual time-rock/time classification and nomenclature redundant? Ismael Ferrusquía-Villafranca1 Robert M. Easton2 and Donald E. Owen3 1Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán, México, DF, MEX, 45100, e-mail: [email protected] 2Ontario Geological Survey, Precambrian Geoscience Section, 933 Ramsey Lake Road, B7064 Sudbury, Ontario P3E 6B5, e-mail: [email protected] 3Department of Geology, Lamar University, Beaumont, Texas 77710, e-mail: [email protected] ABSTRACT: The Geological Society of London Proposal for “…ending the distinction between the dual stratigraphic terminology of time-rock units (of chronostratigraphy) and geologic time units (of geochronology). The long held, but widely misunderstood distinc- tion between these two essentially parallel time scales has been rendered unnecessary by the adoption of the global stratotype sections and points (GSSP-golden spike) principle in defining intervals of geologic time within rock strata.” Our review of stratigraphic princi- ples, concepts, models and paradigms through history clearly shows that the GSL Proposal is flawed and if adopted will be of disservice to the stratigraphic community. We recommend the continued use of the dual stratigraphic terminology of chronostratigraphy and geochronology for the following reasons: (1) time-rock (chronostratigraphic) and geologic time (geochronologic) units are conceptually different; (2) the subtended time-rock’s unit space between its “golden spiked-marked” -
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Chronology and Faunal Evolution of the Middle Eocene Bridgerian North American Land Mammal “Age”: Achieving High Precision Geochronology Kaori Tsukui Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate School of Arts and Sciences COLUMBIA UNIVERSITY 2016 © 2015 Kaori Tsukui All rights reserved ABSTRACT Chronology and Faunal Evolution of the Middle Eocene Bridgerian North American Land Mammal “Age”: Achieving High Precision Geochronology Kaori Tsukui The age of the Bridgerian/Uintan boundary has been regarded as one of the most important outstanding problems in North American Land Mammal “Age” (NALMA) biochronology. The Bridger Basin in southwestern Wyoming preserves one of the best stratigraphic records of the faunal boundary as well as the preceding Bridgerian NALMA. In this dissertation, I first developed a chronological framework for the Eocene Bridger Formation including the age of the boundary, based on a combination of magnetostratigraphy and U-Pb ID-TIMS geochronology. Within the temporal framework, I attempted at making a regional correlation of the boundary-bearing strata within the western U.S., and also assessed the body size evolution of three representative taxa from the Bridger Basin within the context of Early Eocene Climatic Optimum. Integrating radioisotopic, magnetostratigraphic and astronomical data from the early to middle Eocene, I reviewed various calibration models for the Geological Time Scale and intercalibration of 40Ar/39Ar data among laboratories and against U-Pb data, toward the community goal of achieving a high precision and well integrated Geological Time Scale. In Chapter 2, I present a magnetostratigraphy and U-Pb zircon geochronology of the Bridger Formation from the Bridger Basin in southwestern Wyoming. -
Printable Celestial Navigation Work Forms
S T A R P A T H ® S c h o o l o f N a v i g a t i o n PRINTABLE CELESTIAL NAVIGATION WORK FORMS For detailed instructions and numerical examples, see the companion booklet listed below. FORM 104 — All bodies, using Pub 249 or Pub 229 FORM 106 — All Bodies, Using NAO Tables FORM 108 — All Bodies, Almanac, and NAO Tables FORM 109 — Solar Index Correction FORM 107 — Latitude at LAN FORM 110 — Latitude by Polaris FORM 117 — Lat, Lon at LAN plus Polaris FORM 111 — Pub 249, Vol. 1 Selected Stars Other Starpath publications on Celestial Navigation Celestial Navigation Starpath Celestial Navigation Work Forms Hawaii by Sextant How to Use Plastic Sextants The Star Finder Book GPS Backup with a Mark 3 Sextant Emergency Navigation Stark Tables for Clearing the Lunar Distance Long Term Almanac 2000 to 2050 Celestial Navigation Work Form Form 104, All Sights, Pub. 249 or Pub. 229 WT h m s date body Hs ° ´ WE DR log index corr. 1 +S -F Lat + off - on ZD DR HE DIP +W -E Lon ft - UTC h m s UTC date / LOP label Ha ° ´ GHA v Dec d HP ° ´ moon ° ´ + 2 hr. planets hr - moon GHA + d additional ° ´ + ´ altitude corr. m.s. corr. - moon, mars, venus 3 SHA + stars Dec Dec altitude corr. or ° ´ or ° ´ all sights v corr. moon, planets min GHA upper limb moon ° ´ tens d subtract 30’ d upper Ho units d ° ´ a-Lon ° ´ d lower -W+E dsd dsd T LHA corr. + Hc 00´ W / 60´ E ° d. -
The Mathematics of the Chinese, Indian, Islamic and Gregorian Calendars
Heavenly Mathematics: The Mathematics of the Chinese, Indian, Islamic and Gregorian Calendars Helmer Aslaksen Department of Mathematics National University of Singapore [email protected] www.math.nus.edu.sg/aslaksen/ www.chinesecalendar.net 1 Public Holidays There are 11 public holidays in Singapore. Three of them are secular. 1. New Year’s Day 2. Labour Day 3. National Day The remaining eight cultural, racial or reli- gious holidays consist of two Chinese, two Muslim, two Indian and two Christian. 2 Cultural, Racial or Religious Holidays 1. Chinese New Year and day after 2. Good Friday 3. Vesak Day 4. Deepavali 5. Christmas Day 6. Hari Raya Puasa 7. Hari Raya Haji Listed in order, except for the Muslim hol- idays, which can occur anytime during the year. Christmas Day falls on a fixed date, but all the others move. 3 A Quick Course in Astronomy The Earth revolves counterclockwise around the Sun in an elliptical orbit. The Earth ro- tates counterclockwise around an axis that is tilted 23.5 degrees. March equinox June December solstice solstice September equinox E E N S N S W W June equi Dec June equi Dec sol sol sol sol Beijing Singapore In the northern hemisphere, the day will be longest at the June solstice and shortest at the December solstice. At the two equinoxes day and night will be equally long. The equi- noxes and solstices are called the seasonal markers. 4 The Year The tropical year (or solar year) is the time from one March equinox to the next. The mean value is 365.2422 days. -
Isotopegeochemistry Chapter4
Isotope Geochemistry W. M. White Chapter 4 GEOCHRONOLOGY III: OTHER DATING METHODS 4.1 COSMOGENIC NUCLIDES 4.1.1 Cosmic Rays in the Atmosphere As the name implies, cosmogenic nuclides are produced by cosmic rays colliding with atoms in the atmosphere and the surface of the solid Earth. Nuclides so created may be stable or radioactive. Radio- active cosmogenic nuclides, like the U decay series nuclides, have half-lives sufficiently short that they would not exist in the Earth if they were not continually produced. Assuming that the production rate is constant through time, then the abundance of a cosmogenic nuclide in a reservoir isolated from cos- mic ray production is simply given by: −λt N = N0e 4.1 Hence if we know N0 and measure N, we can calculate t. Table 4.1 lists the radioactive cosmogenic nu- clides of principal interest. As we shall, cosmic ray interactions can also produce rare stable nuclides, and their abundance can also be used to measure geologic time. A number of different nuclear reactions create cosmogenic nuclides. “Cosmic rays” are high-energy (several GeV up to 1019 eV!) atomic nuclei, mainly of H and He (because these constitute most of the matter in the universe), but nuclei of all the elements have been recognized. To put these kinds of ener- gies in perspective, the previous gen- eration of accelerators for physics ex- Table 4.1. Data on Cosmogenic Nuclides periments, such as the Cornell Elec- -1 tron Storage Ring produce energies in Nuclide Half-life, years Decay constant, yr the 10’s of GeV (1010 eV); while 14C 5730 1.209x 10-4 CERN’s Large Hadron Collider, 3H 12.33 5.62 x 10-2 mankind’s most powerful accelerator, 10Be 1.500 × 106 4.62 x 10-7 located on the Franco-Swiss border 26Al 7.16 × 105 9.68x 10-5 near Geneva produces energies of 36Cl 3.08 × 105 2.25x 10-6 ~10 TeV range (1013 eV). -
Treasury's Emergency Rental Assistance
FREQUENTLY ASKED QUESTIONS: TREASURY’SHEADING EMERGENCY1 HERE RENTAL ASSISTANCEHEADING (ERA)1 HERE PROGRAM AUGUST 2021 ongress established an Emergency Rental Assistance (ERA) program administered by the U.S. Department of the Treasury to distribute critically needed emergency rent and utility assistance to Cmillions of households at risk of losing their homes. Congress provided more than $46 billion for emergency rental assistance through the Consolidated Appropriations Act enacted in December 2020 and the American Rescue Plan Act enacted in March 2021. Based on NLIHC’s ongoing tracking and analysis of state and local ERA programs, including nearly 500 programs funded through Treasury’s ERA program, NLIHC has continued to identify needed policy changes to ensure ERA is distributed efficiently, effectively, and equitably. The ability of states and localities to distribute ERA was hindered early on by harmful guidance released by the Trump administration on its last day in office. Immediately after President Biden was sworn into office, the administration rescinded the harmful FAQ and released improved guidance to ensure ERA reaches households with the greatest needs, as recommended by NLIHC. The Biden administration issued revised ERA guidance in February, March, May, June, and August that directly addressed many of NLIHC’s concerns about troubling roadblocks in ERA programs. Treasury’s latest guidance provides further clarity and recommendations to encourage state and local governments to expedite assistance. Most notably, the FAQ provides even more explicit permission for ERA grantees to rely on self-attestations without further documentation. WHO IS ELIGIBLE TO RECEIVE EMERGENCY RENTAL ASSISTANCE? Households are eligible for ERA funds if one or more individuals: 1. -
Geologic History of the Earth 1 the Precambrian
Geologic History of the Earth 1 algae = very simple plants that Geologists are scientists who study the structure grow in or near the water of rocks and the history of the Earth. By looking at first = in the beginning at and examining layers of rocks and the fossils basic = main, important they contain they are able to tell us what the beginning = start Earth looked like at a certain time in history and billion = a thousand million what kind of plants and animals lived at that breathe = to take air into your lungs and push it out again time. carbon dioxide = gas that is produced when you breathe Scientists think that the Earth was probably formed at the same time as the rest out of our solar system, about 4.6 billion years ago. The solar system may have be- certain = special gun as a cloud of dust, from which the sun and the planets evolved. Small par- complex = something that has ticles crashed into each other to create bigger objects, which then turned into many different parts smaller or larger planets. Our Earth is made up of three basic layers. The cen- consist of = to be made up of tre has a core made of iron and nickel. Around it is a thick layer of rock called contain = have in them the mantle and around that is a thin layer of rock called the crust. core = the hard centre of an object Over 4 billion years ago the Earth was totally different from the planet we live create = make on today. -
Critical Analysis of Article "21 Reasons to Believe the Earth Is Young" by Jeff Miller
1 Critical analysis of article "21 Reasons to Believe the Earth is Young" by Jeff Miller Lorence G. Collins [email protected] Ken Woglemuth [email protected] January 7, 2019 Introduction The article by Dr. Jeff Miller can be accessed at the following link: http://apologeticspress.org/APContent.aspx?category=9&article=5641 and is an article published by Apologetic Press, v. 39, n.1, 2018. The problems start with the Article In Brief in the boxed paragraph, and with the very first sentence. The Bible does not give an age of the Earth of 6,000 to 10,000 years, or even imply − this is added to Scripture by Dr. Miller and other young-Earth creationists. R. C. Sproul was one of evangelicalism's outstanding theologians, and he stated point blank at the Legionier Conference panel discussion that he does not know how old the Earth is, and the Bible does not inform us. When there has been some apparent conflict, either the theologians or the scientists are wrong, because God is the Author of the Bible and His handiwork is in general revelation. In the days of Copernicus and Galileo, the theologians were wrong. Today we do not know of anyone who believes that the Earth is the center of the universe. 2 The last sentence of this "Article In Brief" is boldly false. There is almost no credible evidence from paleontology, geology, astrophysics, or geophysics that refutes deep time. Dr. Miller states: "The age of the Earth, according to naturalists and old- Earth advocates, is 4.5 billion years. -
Geochronology Database for Central Colorado
Geochronology Database for Central Colorado Data Series 489 U.S. Department of the Interior U.S. Geological Survey Geochronology Database for Central Colorado By T.L. Klein, K.V. Evans, and E.H. DeWitt Data Series 489 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior KEN SALAZAR, Secretary U.S. Geological Survey Marcia K. McNutt, Director U.S. Geological Survey, Reston, Virginia: 2010 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1-888-ASK-USGS For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. Suggested citation: T.L. Klein, K.V. Evans, and E.H. DeWitt, 2009, Geochronology database for central Colorado: U.S. Geological Survey Data Series 489, 13 p. iii Contents Abstract ...........................................................................................................................................................1 Introduction.....................................................................................................................................................1 -
Soils in the Geologic Record
in the Geologic Record 2021 Soils Planner Natural Resources Conservation Service Words From the Deputy Chief Soils are essential for life on Earth. They are the source of nutrients for plants, the medium that stores and releases water to plants, and the material in which plants anchor to the Earth’s surface. Soils filter pollutants and thereby purify water, store atmospheric carbon and thereby reduce greenhouse gasses, and support structures and thereby provide the foundation on which civilization erects buildings and constructs roads. Given the vast On February 2, 2020, the USDA, Natural importance of soil, it’s no wonder that the U.S. Government has Resources Conservation Service (NRCS) an agency, NRCS, devoted to preserving this essential resource. welcomed Dr. Luis “Louie” Tupas as the NRCS Deputy Chief for Soil Science and Resource Less widely recognized than the value of soil in maintaining Assessment. Dr. Tupas brings knowledge and experience of global change and climate impacts life is the importance of the knowledge gained from soils in the on agriculture, forestry, and other landscapes to the geologic record. Fossil soils, or “paleosols,” help us understand NRCS. He has been with USDA since 2004. the history of the Earth. This planner focuses on these soils in the geologic record. It provides examples of how paleosols can retain Dr. Tupas, a career member of the Senior Executive Service since 2014, served as the Deputy Director information about climates and ecosystems of the prehistoric for Bioenergy, Climate, and Environment, the Acting past. By understanding this deep history, we can obtain a better Deputy Director for Food Science and Nutrition, and understanding of modern climate, current biodiversity, and the Director for International Programs at USDA, ongoing soil formation and destruction.