DOCSLIB.ORG

The Student's Elements of Geology

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Student's Elements of Geology The Student's Elements of Geology Sir Charles Lyell The Student's Elements of Geology Table of Contents The Student's Elements of Geology.........................................................................................................................1 Sir Charles Lyell............................................................................................................................................1 PREFACE......................................................................................................................................................2 CHAPTER I. ON THE DIFFERENT CLASSES OF ROCKS.....................................................................2 CHAPTER II. AQUEOUS ROCKS. THEIR COMPOSITION AND FORMS OF STRATIFICATION......................................................................................................................................8 CHAPTER III. ARRANGEMENT OF FOSSILS IN STRATA. FRESH−WATER AND MARINE FOSSILS.....................................................................................................................................................14 CHAPTER IV. CONSOLIDATION OF STRATA AND PETRIFACTION OF FOSSILS.......................21 CHAPTER V. ELEVATION OF STRATA ABOVE THE SEA. HORIZONTAL AND INCLINED STRATIFICATION....................................................................................................................................27 CHAPTER VI. DENUDATION..................................................................................................................40 CHAPTER VII. JOINT ACTION OF DENUDATION, UPHEAVAL, AND SUBSIDENCE IN REMODELLING THE EARTH'S CRUST................................................................................................46 CHAPTER VIII. CHRONOLOGICAL CLASSIFICATION OF ROCKS.................................................53 CHAPTER IX. CLASSIFICATION OF TERTIARY FORMATIONS......................................................66 CHAPTER X. RECENT AND POST−PLIOCENE PERIODS..................................................................71 CHAPTER XI. POST−PLIOCENE PERIOD, CONTINUED. GLACIAL CONDITIONS.....................82 CHAPTER XII. POST−PLIOCENE PERIOD, CONTINUED. GLACIAL CONDITIONS, CONCLUDED............................................................................................................................................86 CHAPTER XIII. PLIOCENE PERIOD.......................................................................................................94 CHAPTER XIV. MIOCENE PERIOD. UPPER MIOCENE..................................................................106 CHAPTER XV. LOWER MIOCENE (OLIGOCENE OF BEYRICH)....................................................116 CHAPTER XVI. EOCENE FORMATIONS.............................................................................................127 CHAPTER XVII. UPPER CRETACEOUS GROUP................................................................................144 CHAPTER XVIII. LOWER CRETACEOUS OR NEOCOMIAN FORMATION..................................158 CHAPTER XIX. JURASSIC GROUP. PURBECK BEDS AND OOLITE...........................................166 CHAPTER XX. JURASSIC GROUP CONTINUED. LIAS................................................................183 CHAPTER XXI. TRIAS, OR NEW RED SANDSTONE GROUP..........................................................189 CHAPTER XXII. PERMIAN OR MAGNESIAN LIMESTONE GROUP..............................................200 CHAPTER XXIII. THE COAL OR CARBONIFEROUS GROUP..........................................................205 CHAPTER XXIV. FLORA AND FAUNA OF THE CARBONIFEROUS PERIOD..............................219 CHAPTER XXV. DEVONIAN OR OLD RED SANDSTONE GROUP.................................................228 CHAPTER XXVI. SILURIAN GROUP...................................................................................................238 CHAPTER XXVII. CAMBRIAN AND LAURENTIAN GROUPS........................................................253 CHAPTER XXVIII. VOLCANIC ROCKS...............................................................................................260 CHAPTER XXIX. ON THE AGES OF VOLCANIC ROCKS................................................................278 CHAPTER XXX. AGE OF VOLCANIC ROCKS CONTINUED...........................................................286 CHAPTER XXXI. PLUTONIC ROCKS..................................................................................................295 CHAPTER XXXII. ON THE DIFFERENT AGES OF THE PLUTONIC ROCKS.................................302 CHAPTER XXXIII. METAMORPHIC ROCKS......................................................................................308 CHAPTER XXXIV. METAMORPHIC ROCKS CONTINUED.............................................................315 CHAPTER XXXV. ON THE DIFFERENT AGES OF THE METAMORPHIC ROCKS.......................319 CHAPTER XXXVI. MINERAL VEINS...................................................................................................324 INDEX.......................................................................................................................................................331 i The Student's Elements of Geology Sir Charles Lyell This page copyright © 2001 Blackmask Online. http://www.blackmask.com • PREFACE. • CHAPTER I. ON THE DIFFERENT CLASSES OF ROCKS. • CHAPTER II. AQUEOUS ROCKS. THEIR COMPOSITION AND FORMS OF STRATIFICATION. • CHAPTER III. ARRANGEMENT OF FOSSILS IN STRATA. FRESH−WATER AND MARINE FOSSILS. • CHAPTER IV. CONSOLIDATION OF STRATA AND PETRIFACTION OF FOSSILS. • CHAPTER V. ELEVATION OF STRATA ABOVE THE SEA. HORIZONTAL AND INCLINED STRATIFICATION. • CHAPTER VI. DENUDATION. • CHAPTER VII. JOINT ACTION OF DENUDATION, UPHEAVAL, AND SUBSIDENCE IN REMODELLING THE EARTH'S CRUST. • CHAPTER VIII. CHRONOLOGICAL CLASSIFICATION OF ROCKS. • CHAPTER IX. CLASSIFICATION OF TERTIARY FORMATIONS. • CHAPTER X. RECENT AND POST−PLIOCENE PERIODS. • CHAPTER XI. POST−PLIOCENE PERIOD, CONTINUED. GLACIAL CONDITIONS. • CHAPTER XII. POST−PLIOCENE PERIOD, CONTINUED. GLACIAL CONDITIONS, CONCLUDED. • CHAPTER XIII. PLIOCENE PERIOD. • CHAPTER XIV. MIOCENE PERIOD. UPPER MIOCENE. • CHAPTER XV. LOWER MIOCENE (OLIGOCENE OF BEYRICH). • CHAPTER XVI. EOCENE FORMATIONS. • CHAPTER XVII. UPPER CRETACEOUS GROUP. • CHAPTER XVIII. LOWER CRETACEOUS OR NEOCOMIAN FORMATION. • CHAPTER XIX. JURASSIC GROUP. PURBECK BEDS AND OOLITE. • CHAPTER XX. JURASSIC GROUP CONTINUED. LIAS. • CHAPTER XXI. TRIAS, OR NEW RED SANDSTONE GROUP. • CHAPTER XXII. PERMIAN OR MAGNESIAN LIMESTONE GROUP. • CHAPTER XXIII. THE COAL OR CARBONIFEROUS GROUP. • CHAPTER XXIV. FLORA AND FAUNA OF THE CARBONIFEROUS PERIOD. • CHAPTER XXV. DEVONIAN OR OLD RED SANDSTONE GROUP. • CHAPTER XXVI. SILURIAN GROUP. • CHAPTER XXVII. CAMBRIAN AND LAURENTIAN GROUPS. • CHAPTER XXVIII. VOLCANIC ROCKS. • CHAPTER XXIX. ON THE AGES OF VOLCANIC ROCKS. • CHAPTER XXX. AGE OF VOLCANIC ROCKS CONTINUED. • CHAPTER XXXI. PLUTONIC ROCKS. • CHAPTER XXXII. ON THE DIFFERENT AGES OF THE PLUTONIC ROCKS. • CHAPTER XXXIII. METAMORPHIC ROCKS. • CHAPTER XXXIV. METAMORPHIC ROCKS CONTINUED. • CHAPTER XXXV. ON THE DIFFERENT AGES OF THE METAMORPHIC ROCKS. • CHAPTER XXXVI. MINERAL VEINS. • INDEX. The Student's Elements of Geology 1 The Student's Elements of Geology Produced by Sue Asscher [email protected] PREFACE. The LAST or sixth EDITION of my "Elements of Geology" was already out of print before the end of 1868, in which year I brought out the tenth edition of my "Principles of Geology." In writing the last−mentioned work I had been called upon to pass in review almost all the leading points of speculation and controversy to which the rapid advance of the science had given rise, and when I proposed to bring out a new edition of the "Elements" I was strongly urged by my friends not to repeat these theoretical discussions, but to confine myself in the new treatise to those parts of the "Elements" which were most indispensable to a beginner. This was to revert, to a certain extent, to the original plan of the first edition; but I found, after omitting a great number of subjects, that the necessity of bringing up to the day those which remained, and adverting, however briefly, to new discoveries, made it most difficult to confine the proposed abridgment within moderate limits. Some chapters had to be entirely recast, some additional illustrations to be introduced, and figures of some organic remains to be replaced by new ones from specimens more perfect than those which had been at my command on former occasions. By these changes the work assumed a form so different from the sixth edition of the "Elements," that I resolved to give it a new title and call it the "Student's Elements of Geology." In executing this task I have found it very difficult to meet the requirements of those who are entirely ignorant of the science. It is only the adept who has already overcome the first steps as an observer, and is familiar with many of the technical terms, who can profit by a brief and concise manual. Beginners wish for a short and cheap book in which they may find a full explanation of the leading facts and principles of Geology. Their wants, I fear, somewhat resemble those of the old woman in New England, who asked a bookseller to supply her with "the cheapest Bible in the largest possible print." But notwithstanding the difficulty of reconciling brevity with the copiousness of illustration demanded by those who have not yet mastered the rudiments of the science, I have endeavoured
Load more

Recommended publications
  • The Stones of Osterley Park House Ruth Siddall
    Urban Geology in London No. 37 The Stones of Osterley Park House Ruth Siddall Osterley Park House was designed and built by Robert Adam (1728-1792) in the late 18th Century, between 1761 and the 1780s. It was commissioned by the Child Family and superseded a Tudor Mansion on the same site. Adam had ‘total design’ control of the construction and interior decoration of the house. This assumes that Adam also had a hand in overseeing if not selecting the building materials used. This brief report summarises the building and decorative stones used in the building, as observed following a visit to Osterley Park House in June 2017. Portico and Courtyard Portland Whitbed is used for the pediment, balustrade, quoins and other stone dressings on the exterior of Osterley Park House. It is also used for paving and for the columns supporting the pediment. This stone is identified by the pale grey colour with darker fossilised shells of oysters, which now weather slightly proud of the surface. Sedimentary bedding alignment can be detected in both columns and in some flagstones due to the concentration of shell beds. Portland Whitbed is the most commonly used of three main building stones extracted from the Portland Limestone Formation which occurs in outcrop and subcrop on the Isle of Portland, a peninsula on the Dorset Coast. Whitbed contains variable fossil content, predominantly in the form of oyster shells with well-preserved, laminated shells and also fragments of the reef-forming algae Solenpora portlandica. Two other units are also extracted as building stone; the Basebed and the Roach.
    [Show full text]
  • A Report on a Community Partnership in Eco-Acoustic Monitoring in Brisbane Ranges National Park, Victoria
    Australian Owlet-nightjar. Photo: Damian Kelly A REPORT ON A COMMUNITY PARTNERSHIP IN ECO-ACOUSTIC MONITORING IN BRISBANE RANGES NATIONAL PARK, VICTORIA Prepared by: Dr Sera Blair, Christine Connelly, Caitlin Griffith, Victorian National Parks Association. Dr Karen Rowe & Dr Amy Adams, Museums Victoria Victorian National Parks Association The Victorian National Parks Association (VNPA) helps to shape the agenda for creating and managing national parks, conservation reserves and other important natural areas across land and sea. We work with all levels of government, the scientific community and the general community to achieve long term, best practice environmental outcomes. The VNPA is also Victoria’s largest bush walking club and provides a range of information, education and activity programs to encourage Victorians to get active for nature. NatureWatch NatureWatch is a citizen science program which engages the community in collecting scientific data on Victorian native plants and animals. The program builds links between community members, scientists and land managers to develop scientific, practical projects that contribute to a better understanding of species and ecosystems, and contributes to improved management of natural areas. Project Partners Museums Victoria Museums Victoria has been trusted with the collection and curation of Victoria’s natural history for over 160 years and serves as a key international research institute and experts in data archiving and long- term data protection. Responding to changing intellectual issues, studying subjects of relevance to the community, providing training and professional development, and working closely with schools, communities, and online visitors, Museums Victoria works to disseminate our collective knowledge through online resources and image, audio and video databases.
    [Show full text]
  • Unclassified Fourteenth- Century Purbeck Marble Incised Slabs
    Reports of the Research Committee of the Society of Antiquaries of London, No. 60 EARLY INCISED SLABS AND BRASSES FROM THE LONDON MARBLERS This book is published with the generous assistance of The Francis Coales Charitable Trust. EARLY INCISED SLABS AND BRASSES FROM THE LONDON MARBLERS Sally Badham and Malcolm Norris The Society of Antiquaries of London First published 1999 Dedication by In memory of Frank Allen Greenhill MA, FSA, The Society of Antiquaries of London FSA (Scot) (1896 to 1983) Burlington House Piccadilly In carrying out our study of the incised slabs and London WlV OHS related brasses from the thirteenth- and fourteenth- century London marblers' workshops, we have © The Society of Antiquaries of London 1999 drawn very heavily on Greenhill's records. His rubbings of incised slabs, mostly made in the 1920s All Rights Reserved. Except as permitted under current legislation, and 1930s, often show them better preserved than no part of this work may be photocopied, stored in a retrieval they are now and his unpublished notes provide system, published, performed in public, adapted, broadcast, much invaluable background information. Without transmitted, recorded or reproduced in any form or by any means, access to his material, our study would have been less without the prior permission of the copyright owner. complete. For this reason, we wish to dedicate this volume to Greenhill's memory. ISBN 0 854312722 ISSN 0953-7163 British Library Cataloguing in Publication Data A CIP catalogue record for this book is available from the
    [Show full text]
  • Stratigraphy of the Upper Cretaceous Fox Hills Sandstone and Adjacent
    Stratigraphy of the Upper Cretaceous Fox Hills Sandstone and AdJa(-erit Parts of the Lewis Sliale and Lance Formation, East Flank of the Rock Springs Uplift, Southwest lo U.S. OEOLOGI AL SURVEY PROFESSIONAL PAPER 1532 Stratigraphy of the Upper Cretaceous Fox Hills Sandstone and Adjacent Parts of the Lewis Shale and Lance Formation, East Flank of the Rock Springs Uplift, Southwest Wyoming By HENRYW. ROEHLER U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 1532 Description of three of/lapping barrier shorelines along the western margins of the interior seaway of North America UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1993 U.S. DEPARTMENT OF THE INTERIOR BRUCE BABBITT, Secretary U.S. GEOLOGICAL SURVEY Dallas L. Peck, Director Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government. Library of Congress Cataloging-in-Publication Data Roehler, Henry W. Stratigraphy of the Upper Cretaceous Fox Hills sandstone and adjacent parts of the Lewis shale and Lance formation, east flank of the Rock Springs Uplift, southwest Wyoming / by Henry W. Roehler. p. cm. (U.S. Geological Survey professional paper ; 1532) Includes bibliographical references. Supt.ofDocs.no.: I19.16:P1532 1. Geology, Stratigraphic Cretaceous. 2. Geology Wyoming. 3. Fox Hills Formation. I. Geological Survey (U.S.). II. Title. III. Series. QE688.R64 1993 551.7T09787 dc20 92-36645 CIP For sale by USGS Map Distribution Box 25286, Building 810 Denver Federal Center Denver, CO 80225 CONTENTS Page Page Abstract......................................................................................... 1 Stratigraphy Continued Introduction................................................................................... 1 Formations exposed on the east flank of the Rock Springs Description and accessibility of the study area ................
    [Show full text]
  • Australia's Ildlife Onders
    GREAT SOUTHERN TOURING ROUTE AUSTRALIA’S AUSTRALIA ILDLIFE ONDERS VICTORIA www.greatsoutherntouring.com.au BOTANICA WORLD DISCOVERIES For those seeking a specialist garden tour along the Great Southern Touring Route or other Australian destinations we recommend Botanica World Discoveries. The Victorian Homesteads, Gardens and Mansions tour follows the Great Southern Touring Route and provides special access to gardens that will inspire and delight those with ‘green thumbs and the love of gardens.’ www.botanica.travel MEET THE ARTIST Australia’s Great Southern Touring Route is widely regarded as the ‘journey of a lifetime’. This road trip captures the essence of Australia particularly the wildlife encounters to be experienced along the way. In a unique partnership between Great Southern Touring Route and Willie Wildlife Sculptures the amazing wildlife and dramatic landscapes are paired together and presented as joint heroes. Will Wilson’s sculptures of our wondrous native animals and birds inspire the traveller to explore and there is no better place to do this than the Great Southern Touring Route. From coastal cliffs, pristine beaches to ancient rainforests and mountain ranges the diverse protected landscapes of the Great Southern Touring Route are not only spectacular but also the home of a dazzling variety of birds, sea creatures and native animals. The skilful hands of Will Wilson captures the shape and form of these Australian native animals but also give an insight into their personality and character. Willie Wildlife Sculpture gallery is located in The Hive Ocean Grove on the Bellarine Peninsula. This guide is a celebration of art and wildlife as nature unfolds at every turn along this iconic Aussie road trip.
    [Show full text]
  • UNEP/CBD/RW/EBSA/SIO/1/4 26 June 2013
    CBD Distr. GENERAL UNEP/CBD/RW/EBSA/SIO/1/4 26 June 2013 ORIGINAL: ENGLISH SOUTHERN INDIAN OCEAN REGIONAL WORKSHOP TO FACILITATE THE DESCRIPTION OF ECOLOGICALLY OR BIOLOGICALLY SIGNIFICANT MARINE AREAS Flic en Flac, Mauritius, 31 July to 3 August 2012 REPORT OF THE SOUTHERN INDIAN OCEAN REGIONAL WORKSHOP TO FACILITATE THE DESCRIPTION OF ECOLOGICALLY OR BIOLOGICALLY SIGNIFICANT MARINE AREAS1 INTRODUCTION 1. In paragraph 36 of decision X/29, the Conference of the Parties to the Convention on Biological Diversity (COP 10) requested the Executive Secretary to work with Parties and other Governments as well as competent organizations and regional initiatives, such as the Food and Agriculture Organization of the United Nations (FAO), regional seas conventions and action plans, and, where appropriate, regional fisheries management organizations (RFMOs), with regard to fisheries management, to organize, including the setting of terms of reference, a series of regional workshops, with a primary objective to facilitate the description of ecologically or biologically significant marine areas (EBSAs) through the application of scientific criteria in annex I of decision IX/20, and other relevant compatible and complementary nationally and intergovernmentally agreed scientific criteria, as well as the scientific guidance on the identification of marine areas beyond national jurisdiction, which meet the scientific criteria in annex I to decision IX/20. 2. In the same decision (paragraph 41), the Conference of the Parties requested that the Executive Secretary make available the scientific and technical data and information and results collated through the workshops referred to above to participating Parties, other Governments, intergovernmental agencies and the Subsidiary Body on Scientific, Technical and Technological Advice (SBSTTA) for their use according to their competencies.
    [Show full text]
  • The English Claim to Gothic: Contemporary Approaches to an Age-Old Debate (Under the Direction of DR STEFAAN VAN LIEFFERINGE)
    ABSTRACT MARY ELIZABETH BLUME The English Claim to Gothic: Contemporary Approaches to an Age-Old Debate (Under the Direction of DR STEFAAN VAN LIEFFERINGE) The Gothic Revival of the nineteenth century in Europe aroused a debate concerning the origin of a style already six centuries old. Besides the underlying quandary of how to define or identify “Gothic” structures, the Victorian revivalists fought vehemently over the national birthright of the style. Although Gothic has been traditionally acknowledged as having French origins, English revivalists insisted on the autonomy of English Gothic as a distinct and independent style of architecture in origin and development. Surprisingly, nearly two centuries later, the debate over Gothic’s nationality persists, though the nationalistic tug-of-war has given way to the more scholarly contest to uncover the style’s authentic origins. Traditionally, scholarship took structural or formal approaches, which struggled to classify structures into rigidly defined periods of formal development. As the Gothic style did not develop in such a cleanly linear fashion, this practice of retrospective labeling took a second place to cultural approaches that consider the Gothic style as a material manifestation of an overarching conscious Gothic cultural movement. Nevertheless, scholars still frequently look to the Isle-de-France when discussing Gothic’s formal and cultural beginnings. Gothic historians have entered a period of reflection upon the field’s historiography, questioning methodological paradigms. This
    [Show full text]
  • Coral Reef Resilience Assessment of the Pemba Channel Conservation Area, Tanzania
    Coral Reef Resilience Assessment of the Pemba Channel Conservation Area, Tanzania G. Grimsditch, J. Tamelander, J. Mwaura, M. Zavagli, Y. Takata, T. Gomez Published August 2009 from Survey in Febuary 2009 IUCN CLIMATE CHANGE AND CORAL REEFS WORKING GROUP I The designation of geographical entities in this book, and the presentation of the material, do not imply the expression of any opinion whatsoever on the part of IUCN, CCCR, CORDIO, Pemba Alive, RAMSAR, or the Manta Resort concerning the legal status of any country, territory, or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. The views expressed in this publication do not necessarily reflect those of IUCN, CCCR, CORDIO, Pemba Alive, RAMSAR, or the Manta Resort. We would like to thank the MacArthur Foundation and the Manta Resort for their generous support which made this study possible. We would also like to thank Ali Said, Pemba Channel Conservation Area (PeCCA), and Zahor Mohamed, Marine Conservation Unit, for enabling and assisting with this research. Published by: IUCN, Gland, Switzerland Copyright: © 2009 IUCN/CORDIO Reproduction of this publication for educational or other non-commercial purposes is authorized without prior written permission from the copyright holder provided the source is fully acknowledged. Reproduction of this publication for resale or other commercial purposes is prohibited without prior written permission of the copyright holder. Citation: Grimsditch G., Tamelander J., Mwaura J., Zavagli M., Takata Y., Gomez T.
    [Show full text]
  • Download Vol. 11, No. 3
    BULLETIN OF THE FLORIDA STATE MUSEUM BIOLOGICAL SCIENCES Volume 11 Number 3 CATALOGUE OF FOSSIL BIRDS: Part 3 (Ralliformes, Ichthyornithiformes, Charadriiformes) Pierce Brodkorb M,4 * . /853 0 UNIVERSITY OF FLORIDA Gainesville 1967 Numbers of the BULLETIN OF THE FLORIDA STATE MUSEUM are pub- lished at irregular intervals. Volumes contain about 800 pages and are not nec- essarily completed in any one calendar year. WALTER AuFFENBERC, Managing Editor OLIVER L. AUSTIN, JA, Editor Consultants for this issue. ~ HILDEGARDE HOWARD ALExANDER WErMORE Communications concerning purchase or exchange of the publication and all manuscripts should be addressed to the Managing Editor of the Bulletin, Florida State Museum, Seagle Building, Gainesville, Florida. 82601 Published June 12, 1967 Price for this issue $2.20 CATALOGUE OF FOSSIL BIRDS: Part 3 ( Ralliformes, Ichthyornithiformes, Charadriiformes) PIERCE BRODKORBl SYNOPSIS: The third installment of the Catalogue of Fossil Birds treats 84 families comprising the orders Ralliformes, Ichthyornithiformes, and Charadriiformes. The species included in this section number 866, of which 215 are paleospecies and 151 are neospecies. With the addenda of 14 paleospecies, the three parts now published treat 1,236 spDcies, of which 771 are paleospecies and 465 are living or recently extinct. The nominal order- Diatrymiformes is reduced in rank to a suborder of the Ralliformes, and several generally recognized families are reduced to subfamily status. These include Geranoididae and Eogruidae (to Gruidae); Bfontornithidae
    [Show full text]
  • (Silurian) Anoxic Palaeo-Depressions at the Western Margin of the Murzuq Basin (Southwest Libya), Based on Gamma-Ray Spectrometry in Surface Exposures
    GeoArabia, Vol. 11, No. 3, 2006 Gulf PetroLink, Bahrain Identification of early Llandovery (Silurian) anoxic palaeo-depressions at the western margin of the Murzuq Basin (southwest Libya), based on gamma-ray spectrometry in surface exposures Nuri Fello, Sebastian Lüning, Petr Štorch and Jonathan Redfern ABSTRACT Following the melting of the Gondwanan icecap and the resulting postglacial sea- level rise, organic-rich shales were deposited in shelfal palaeo-depressions across North Africa and Arabia during the latest Ordovician to earliest Silurian. The unit is absent on palaeohighs that were flooded only later when the anoxic event had already ended. The regional distribution of the Silurian black shale is now well-known for the subsurface of the central parts of the Murzuq Basin, in Libya, where many exploration wells have been drilled and where the shale represents the main hydrocarbon source rock. On well logs, the Silurian black shale is easily recognisable due to increased uranium concentrations and, therefore, elevated gamma-ray values. The uranium in the shales “precipitated” under oxygen- reduced conditions and generally a linear relationship between uranium and organic content is developed. The distribution of the Silurian organic-rich shales in the outcrop belts surrounding the Murzuq Basin has been long unknown because Saharan surface weathering has commonly destroyed the organic matter and black colour of the shales, making it complicated to identify the previously organic-rich unit in the field. In an attempt to distinguish (previously) organic-rich from organically lean shales at outcrop, seven sections that straddle the Ordovician-Silurian boundary were measured by portable gamma-ray spectrometer along the outcrops of the western margin of the Murzuq Basin.
    [Show full text]
  • Geological Survey of Ohio
    GEOLOGICAL SURVEY OF OHIO. VOL. I.—PART II. PALÆONTOLOGY. SECTION II. DESCRIPTIONS OF FOSSIL FISHES. BY J. S. NEWBERRY. Digital version copyrighted ©2012 by Don Chesnut. THE CLASSIFICATION AND GEOLOGICAL DISTRIBUTION OF OUR FOSSIL FISHES. So little is generally known in regard to American fossil fishes, that I have thought the notes which I now give upon some of them would be more interesting and intelligible if those into whose hands they will fall could have a more comprehensive view of this branch of palæontology than they afford. I shall therefore preface the descriptions which follow with a few words on the geological distribution of our Palæozoic fishes, and on the relations which they sustain to fossil forms found in other countries, and to living fishes. This seems the more necessary, as no summary of what is known of our fossil fishes has ever been given, and the literature of the subject is so scattered through scientific journals and the proceedings of learned societies, as to be practically inaccessible to most of those who will be readers of this report. I. THE ZOOLOGICAL RELATIONS OF OUR FOSSIL FISHES. To the common observer, the class of Fishes seems to be well defined and quite distin ct from all the other groups o f vertebrate animals; but the comparative anatomist finds in certain unusual and aberrant forms peculiarities of structure which link the Fishes to the Invertebrates below and Amphibians above, in such a way as to render it difficult, if not impossible, to draw the lines sharply between these great groups.
    [Show full text]
  • (Anthozoa) from the Lower Oligocene (Rupelian) of the Eastern Alps, Austria
    TO L O N O G E I L C A A P I ' T A A T L E I I A Bollettino della Società Paleontologica Italiana, 59 (3), 2020, 319-336. Modena C N O A S S. P. I. Scleractinian corals (Anthozoa) from the lower Oligocene (Rupelian) of the Eastern Alps, Austria Rosemarie Christine Baron-Szabo* & Diethard Sanders R.C. Baron-Szabo, Department of Invertebrate Zoology, Smithsonian Institution, NMNH, W-205, MRC 163, P.O. Box 37012, Washington DC, 20013- 7012 USA; Forschungsinstitut Senckenberg, Senckenberganlage 25, D-60325 Frankfurt/Main, Germany; [email protected]; Rosemarie.Baron- [email protected] *corresponding author D. Sanders, Institut für Geologie, Universität of Innsbruck, Innrain 52, A-6020 Innsbruck, Austria; [email protected] KEY WORDS - Scleractinia, taxonomy, paleoecology, paleobiogeography. ABSTRACT - In the Werlberg Member (Rupelian pro parte) of the Paisslberg Formation (Eastern Alps), an assemblage of colonial corals of eleven species pertaining to eleven genera and eleven families was identified:Stylocoenia carryensis, Acropora lavandulina, ?Colpophyllia sp., Dendrogyra intermedia, Caulastraea pseudoflabellum, Hydnophyllia costata, Pindosmilia cf. brunni, Actinacis rollei, Pavona profunda, Agathiphyllia gregaria, and Faksephyllia faxoensis. This is the first Oligocene coral assemblage reported from the Paisslberg Formation (Werlberg Member) of the Eastern Alps, consisting exclusively of colonial forms. The assemblage represents the northernmost fauna of reefal corals reported to date for Rupelian time. The Werlberg Member accumulated during marine transgression onto a truncated succession of older carbonate rocks. The corals grew as isolated colonies and in carpets in a protected shoreface setting punctuated by high-energy events. Coral growth forms comprise massive to sublamellar forms, and branched (dendroid, ramose) forms.
    [Show full text]