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Geological Timeline
Geological Timeline In this pack you will find information and activities to help your class grasp the concept of geological time, just how old our planet is, and just how young we, as a species, are. Planet Earth is 4,600 million years old. We all know this is very old indeed, but big numbers like this are always difficult to get your head around. The activities in this pack will help your class to make visual representations of the age of the Earth to help them get to grips with the timescales involved. Important EvEnts In thE Earth’s hIstory 4600 mya (million years ago) – Planet Earth formed. Dust left over from the birth of the sun clumped together to form planet Earth. The other planets in our solar system were also formed in this way at about the same time. 4500 mya – Earth’s core and crust formed. Dense metals sank to the centre of the Earth and formed the core, while the outside layer cooled and solidified to form the Earth’s crust. 4400 mya – The Earth’s first oceans formed. Water vapour was released into the Earth’s atmosphere by volcanism. It then cooled, fell back down as rain, and formed the Earth’s first oceans. Some water may also have been brought to Earth by comets and asteroids. 3850 mya – The first life appeared on Earth. It was very simple single-celled organisms. Exactly how life first arose is a mystery. 1500 mya – Oxygen began to accumulate in the Earth’s atmosphere. Oxygen is made by cyanobacteria (blue-green algae) as a product of photosynthesis. -
Radiocarbon Dating and Its Applications in Quaternary Studies
Eiszeitalter und Gegenwart 57/1–2 2–24 Hannover 2008 Quaternary Science Journal Radiocarbon dating and its applications in Quaternary studies *) IRKA HAJDAS Abstract: This paper gives an overview of the origin of 14C, the global carbon cycle, anthropogenic impacts on the atmospheric 14C content and the background of the radiocarbon dating method. For radiocarbon dating, important aspects are sample preparation and measurement of the 14C content. Recent advances in sample preparation allow better understanding of long-standing problems (e.g., contamination of bones), which helps to improve chronologies. In this review, various preparation techniques applied to typical sample types are described. Calibration of radiocarbon ages is the fi nal step in establishing chronologies. The present tree ring chronology-based calibration curve is being constantly pushed back in time beyond the Holocene and the Late Glacial. A reliable calibration curve covering the last 50,000-55,000 yr is of great importance for both archaeology as well as geosciences. In recent years, numerous studies have focused on the extension of the radiocarbon calibration curve (INTCAL working group) and on the reconstruction of palaeo-reservoir ages for marine records. [Die Radiokohlenstoffmethode und ihre Anwendung in der Quartärforschung] Kurzfassung: Dieser Beitrag gibt einen Überblick über die Herkunft von Radiokohlenstoff, den globalen Kohlenstoffkreislauf, anthropogene Einfl üsse auf das atmosphärische 14C und die Grundlagen der Radio- kohlenstoffmethode. Probenaufbereitung und das Messen der 14C Konzentration sind wichtige Aspekte im Zusammenhang mit der Radiokohlenstoffdatierung. Gegenwärtige Fortschritte in der Probenaufbereitung erlauben ein besseres Verstehen lang bekannter Probleme (z.B. die Kontamination von Knochen) und haben zu verbesserten Chronologien geführt. -
Forensic Radiocarbon Dating of Human Remains: the Past, the Present, and the Future
AEFS 1.1 (2017) 3–16 Archaeological and Environmental Forensic Science ISSN (print) 2052-3378 https://doi.org.10.1558/aefs.30715 Archaeological and Environmental Forensic Science ISSN (online) 2052-3386 Forensic Radiocarbon Dating of Human Remains: The Past, the Present, and the Future Fiona Brock1 and Gordon T. Cook2 1. Cranfield Forensic Institute, Cranfield University 2. Scottish Universities Environmental Research Centre [email protected] Radiocarbon dating is a valuable tool for the forensic examination of human remains in answering questions as to whether the remains are of forensic or medico-legal interest or archaeological in date. The technique is also potentially capable of providing the year of birth and/or death of an individual. Atmospheric radiocarbon levels are cur- rently enhanced relative to the natural level due to the release of large quantities of radiocarbon (14C) during the atmospheric nuclear weapons testing of the 1950s and 1960s. This spike, or “bomb-pulse,” can, in some instances, provide precision dates to within 1–2 calendar years. However, atmospheric 14C activity has been declining since the end of atmospheric weapons testing in 1963 and is likely to drop below the natural level by the mid-twenty-first century, with implications for the application of radio- carbon dating to forensic specimens. Introduction Radiocarbon dating is most routinely applied to archaeological and environmental studies, but in some instances can be a very powerful tool for forensic specimens. Radiocarbon (14C) is produced naturally in the upper atmosphere by the interaction of cosmic rays on nitrogen-14 (14N). The 14C produced is rapidly oxidised to carbon dioxide, which then either enters the terrestrial biosphere via photosynthesis and proceeds along the food chain via herbivores and omnivores, and subsequently car- nivores, or exchanges into marine reservoirs where it again enters the food chain by photosynthesis. -
Timing Accuracy of Web Applications on Touchscreen and Keyboard Devices
Behavior Research Methods https://doi.org/10.3758/s13428-019-01321-2 Mental chronometry in the pocket? Timing accuracy of web applications on touchscreen and keyboard devices Thomas Pronk1,2 & Reinout W. Wiers1 & Bert Molenkamp1,2 & Jaap Murre1 # The Author(s) 2020 Abstract Web applications can implement procedures for studying the speed of mental processes (mental chronometry) and can be administered via web browsers on most commodity desktops, laptops, smartphones, and tablets. This approach to conducting mental chronometry offers various opportunities, such as increased scale, ease of data collection, and access to specific samples. However, validity and reliability may be threatened by less accurate timing than specialized software and hardware can offer. We examined how accurately web applications time stimuli and register response times (RTs) on commodity touchscreen and keyboard devices running a range of popular web browsers. Additionally, we explored the accuracy of a range of technical innovations for timing stimuli, presenting stimuli, and estimating stimulus duration. The results offer some guidelines as to what methods may be most accurate and what mental chronometry paradigms may suitably be administered via web applications. In controlled circumstances, as can be realized in a lab setting, very accurate stimulus timing and moderately accurate RT mea- surements could be achieved on both touchscreen and keyboard devices, though RTs were consistently overestimated. In uncontrolled circumstances, such as researchers may encounter online, stimulus presentation may be less accurate, especially when brief durations are requested (of up to 100 ms). Differences in RT overestimation between devices might not substantially affect the reliability with which group differences can be found, but they may affect reliability for individual differences. -
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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. -
Mental Chronometry and the Unification of Differential Psychology
P1: JPJ/KKR P2: GKW/KKR QC: GKW/KKR T1: GKW 0521827442c02 CB738-Sternberg-v1 January 25, 2005 14:54 2 Mental Chronometry and the Unification of Differential Psychology Arthur R. Jensen Mental chronometry is the measurement of cognitive speed. It is the actual time taken to process information of different types and degrees of com- plexity. The basic measurements are an individual’s response time (RT) to a visual or auditory stimulus that calls for a particular response, choice, or decision. Since at least the time of Sir Francis Galton (1822–1911), the father of differential psychology, it has been hypothesized by him and many others that mental speed is a major aspect of general intelligence. What we now know for sure is that RT can be a highly precise, reliable, and sensitive measure of individual differences. Its relationship to other psychological and ecological variables, however, is a complex affair just recently being explored. Research on RT has a venerable history. Not only was it the earliest mea- surement technique used in empirical psychology, but also its scientific use as a measure of individual differences preceded the beginning of experi- mental psychology by at least half a century. The first published research on RT appeared in astronomy journals. Time, as measured by the Earth’s rotation with reference to a star’s moment of transit across a hairline in the lens of a telescope, had to be measured as accurately as possible. In 1796 it was accidentally discovered by the Astronomer Royal at the Greenwich Observatory that astronomers showed individual differences in RT to the star’s transit across the hairline. -
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. -
Confronting History on Campus
CHRONICLEFocusFocus THE CHRONICLE OF HIGHER EDUCATION Confronting History on Campus As a Chronicle of Higher Education individual subscriber, you receive premium, unrestricted access to the entire Chronicle Focus collection. Curated by our newsroom, these booklets compile the most popular and relevant higher-education news to provide you with in-depth looks at topics affecting campuses today. The Chronicle Focus collection explores student alcohol abuse, racial tension on campuses, and other emerging trends that have a significant impact on higher education. ©2016 by The Chronicle of Higher Education Inc. All rights reserved. No part of this publication may be reproduced, forwarded (even for internal use), hosted online, distributed, or transmitted in any form or by any means, including photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the publisher, except in the case of brief quotations embodied in critical reviews and certain other noncommercial uses permitted by copyright law. For bulk orders or special requests, contact The Chronicle at [email protected] ©2016 THE CHRONICLE OF HIGHER EDUCATION INC. TABLE OF CONTENTS OODROW WILSON at Princeton, John Calhoun at Yale, Jefferson Davis at the University of Texas at Austin: Students, campus officials, and historians are all asking the question, What’sW in a name? And what is a university’s responsibil- ity when the name on a statue, building, or program on campus is a painful reminder of harm to a specific racial group? Universities have been grappling anew with those questions, and trying different approaches to resolve them. Colleges Struggle Over Context for Confederate Symbols 4 The University of Mississippi adds a plaque to a soldier’s statue to explain its place there. -
The Geologic Time Scale Is the Eon
Exploring Geologic Time Poster Illustrated Teacher's Guide #35-1145 Paper #35-1146 Laminated Background Geologic Time Scale Basics The history of the Earth covers a vast expanse of time, so scientists divide it into smaller sections that are associ- ated with particular events that have occurred in the past.The approximate time range of each time span is shown on the poster.The largest time span of the geologic time scale is the eon. It is an indefinitely long period of time that contains at least two eras. Geologic time is divided into two eons.The more ancient eon is called the Precambrian, and the more recent is the Phanerozoic. Each eon is subdivided into smaller spans called eras.The Precambrian eon is divided from most ancient into the Hadean era, Archean era, and Proterozoic era. See Figure 1. Precambrian Eon Proterozoic Era 2500 - 550 million years ago Archaean Era 3800 - 2500 million years ago Hadean Era 4600 - 3800 million years ago Figure 1. Eras of the Precambrian Eon Single-celled and simple multicelled organisms first developed during the Precambrian eon. There are many fos- sils from this time because the sea-dwelling creatures were trapped in sediments and preserved. The Phanerozoic eon is subdivided into three eras – the Paleozoic era, Mesozoic era, and Cenozoic era. An era is often divided into several smaller time spans called periods. For example, the Paleozoic era is divided into the Cambrian, Ordovician, Silurian, Devonian, Carboniferous,and Permian periods. Paleozoic Era Permian Period 300 - 250 million years ago Carboniferous Period 350 - 300 million years ago Devonian Period 400 - 350 million years ago Silurian Period 450 - 400 million years ago Ordovician Period 500 - 450 million years ago Cambrian Period 550 - 500 million years ago Figure 2. -
DECODING the PAST: the Work of Archaeologists
to TEACHINGRT WITH THE POWER OOOF OBJECTS Smithsonian Institution November/December 1995 DECODING THE PAST: The Work of Archaeologists Inside Subjects Grades Publication of Art to Zoo is made possible Lesson Plan Social Studies 4–9 through the generous support of the Pacific Take-Home Page Science Mutual Foundation. in English/Spanish Language Arts CONTENTS Introduction page 3 Lesson Plan Step 1 page 6 Worksheet 1 page 7 Lesson Plan Step 2 page 8 Worksheet 2 page 9 Lesson Plan Step 3 page 10 Take-Home Page page 11 Take-Home Page in Spanish page 13 Resources page 15 Art to Zoo’s purpose is to help teachers bring into their classrooms the educational power of museums and other community resources. Art to Zoo draws on the Smithsonian’s hundreds of exhibitions and programs—from art, history, and science to aviation and folklife—to create classroom- ready materials for grades four through nine. Each of the four annual issues explores a single topic through an interdisciplinary, multicultural Above photo: The layering of the soil can tell archaeologists much about the past. (Big Bend Reservoir, South Dakota) approach. The Smithsonian invites teachers to duplicate Cover photo: Smithsonian Institution archaeologists take a Art to Zoo materials for educational use. break during the River Basin Survey project, circa 1950. DECODING THE PAST: The Work of Archaeologists Whether you’re ten or one hundred years old, you have a sense of the past—the human perception of the passage of time, as recent as an hour ago or as far back as a decade ago.