The Upper Ordovician Glaciation in Sw Libya – a Subsurface Perspective
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Biostratigraphic Precision of the Cruziana Rugosa Group: a Study from the Ordovician Succession of Southern and Central Bolivia
Geol. Mag. 144 (2), 2007, pp. 289–303. c 2007 Cambridge University Press 289 doi:10.1017/S0016756807003093 First published online 9 February 2007 Printed in the United Kingdom Biostratigraphic precision of the Cruziana rugosa group: a study from the Ordovician succession of southern and central Bolivia SVEN O. EGENHOFF∗, BERND WEBER†, OLIVER LEHNERT‡ &JORG¨ MALETZ§ ∗Colorado State University, Department of Geosciences, 322 Natural Resources Building, Fort Collins, CO 80523-1482, USA †Freie Universitat¨ Berlin, Institut fur¨ Geologische Wissenschaften, Fachrichtung Geologie, Malteserstrasse 74-100, D-12249 Berlin, Germany ‡University of Erlangen, Institute of Geology and Mineralogie, Schlossgarten 5, D-91054 Erlangen, Germany §Department of Geology, State University of New York at Buffalo, 772 Natural Sciences and Mathematics Complex, Buffalo, New York 14260-3050, USA (Received 10 October 2005; revised version received 1 May 2006; accepted 22 May 2006) Abstract – Cruziana ichnospecies have been repeatedly reported to have biostratigraphic significance. This study presents a re-evaluation of the arthropod ichnotaxa of the Cruziana rugosa Group from bio- and/or lithostratigraphically well-defined Lower to Upper Ordovician siliciclastic sections of southern and central Bolivia. With the exception of Cruziana rouaulti, the ichnofaunas contain all the members of the Cruziana rugosa Group throughout the Ordovician (Arenig to Caradoc) successions in Bolivia. The Bolivian material therefore indicates that these arthropod ichnofossil assemblages are suitable for recognizing Ordovician strata in Bolivia. These findings cast doubt on their use as reliable indicators for a global intra-Ordovician (Arenig to Caradoc) biozonation of Peri-Gondwanan sedimentary successions. Keywords: Cruziana, biostratigraphy, Bolivia, Ordovician. 1. Introduction to the present study. -
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https://doi.org/10.24199/j.mmv.1939.11.02 November 1939 MEM. NAT. Mus. VrcT., XI, 193Q. GRAPTOLITES OF AUSTRALIA: BIBLIOGRAPHY AND HISTORY OF RESEARCH By R. A. Keble, F.G.S. ( Palaeontologist, National 1J1usem·n, JJ:[elboiirne) and Professor TV. N. Benson, B.A., D.Sc. (University of Otago, Dunedin, New Zealcind.) The Australian graptolite fauna is probably the most complete in the world, certainly in regard to its Ordovician components, a fact clearly appreciated by McCoy. He had ready for the press descriptions and figures of most of the species afterwards described in J amcs Hall's J\fonograph published iu 1865, which may be regarded as the basis of systematic graptolite research, when he received from Hall a proof of his fignres. McCoy immediately conceded him priority and adopted his specific names. Had Hall delayed sending his proof, McCoy wonld certainly have pnblisl1ed his figures and descriptions and his name would have been just as pl'ominent in the literature of graptoliies as Hall's. Com menting on "Graptolitcs (Didymograpsus) frutieosus (Hall sp.)," l\IcCoy snys, "this is the first Victorian gmptolitc I ever smv, and, as it was then a new species, I had named it in my .MSS. after J\fr. J. A. Panton, who found it iu the soft shalcs of Bcn(Ugo, of ·which goldficld he was then "\Varden, nncl in ·whose hospitable camp I was then able to recognize the true g-cological age of the gold-bearing Rlates of the colony for the first time. �rhe same species was subsequently dis covered by Professor Hall in Canada; aud ns he kindly sent me an early proof of his illustration before publication, I of course adopted his name as above" (Prod. -
Crossing the Several Scales of Strain-Accomplishing Mechanisms in the Hinterland of the Central Andean Fold±Thrust Belt, Bolivia
Journal of Structural Geology 24 02002) 1587±1602 www.elsevier.com/locate/jstrugeo Crossing the several scales of strain-accomplishing mechanisms in the hinterland of the central Andean fold±thrust belt, Bolivia Nadine McQuarriea,b,*, George H.Davis a aDepartment of Geosciences, University of Arizona, Tucson, AZ 85721, USA bDivision of Geological andPlanetary Science, California Institute of Technology, Pasadena, CA 91125, USA Received 14 November 2000; revised 28 October 2001; accepted 29 October 2001 Abstract Depictions of structures at outcrop, regional and tectonic scales enforce horizontal shortening and vertical thickening as the predominant style of deformation at all scales within the hinterland of the central Andean fold±thrust belt.Outcrop-scale structures document a progression of strain that created: 01) ¯exural-slip folds, 02) fold ¯attening via axial-planar cleavage, 03) vertical stretching via boudinage and late-stage faulting and, ®nally, 04) kink folding.These examples of intraformational deformation are generally concentrated just beyond the tip lines of thrust faults, where fault-propagation folds and related structures are well developed.Fault-propagation folding accommo- dated the accrual of strain indicated by outcrop-scale structures while the structures themselves indicate how deformation developed within each individual fold.Fault-propagation fold geometries at a regional scale emerge from the construction of regional balanced cross-sections. The sections were drawn with careful attention to: 01) known map relationships, -
Copertina Guida Ai TRILOBITI V3 Esterno
Enrico Bonino nato in provincia di Bergamo nel 1966, Enrico si è laureato in Geologia presso il Dipartimento di Scienze della Terra dell'Università di Genova. Attualmente risiede in Belgio dove svolge attività come specialista nel settore dei Sistemi di Informazione Geografica e analisi di immagini digitali. Curatore scientifico del Museo Back to the Past, ha pubblicato numerosi volumi di paleontologia in lingua italiana e inglese, collaborando inoltre all’elaborazione di testi e pubblicazioni scientifiche a livello nazonale e internazionale. Oltre alla passione per questa classe di artropodi, i suoi interessi sono orientati alle forme di vita vissute nel Precambriano, stromatoliti, e fossilizzazioni tipo konservat-lagerstätte. Carlo Kier nato a Milano nel 1961, Carlo si è laureato in Legge, ed è attualmente presidente della catena di alberghi Azul Hotel. Risiede a Cancun, Messico, dove si dedica ad attività legate all'ambiente marino. All'età di 16 anni, ha iniziato una lunga collaborazione con il Museo di Storia Naturale di Milano, ed è a partire dal 1970 che prese inizio la vera passione per i trilobiti, dando avvio a quella che oggi è diventata una delle collezioni paleontologiche più importanti al mondo. La sua instancabile attività di ricerca sul terreno in varie parti del globo e la collaborazione con professionisti del settore, ha permesso la descrizione di nuove specie di trilobiti ed artropodi. Una forte determinazione e la costruzione di un nuovo complesso alberghiero (AZUL Sensatori) hanno infine concretizzzato la realizzazione -
Enrollment and Coaptations in Some Species of the Ordovician Trilobite Genus Placoparia
Enrollment and coaptations in some sp eeies of the Ordovician trilobite genus Placoparia JEAN-LOUIS HENRY AND EUAN N.K. CLARKSON Henry, J.-L. & Clarkson, E.N.K. 1974 12 15: Enrollment and coaptations in some species of the Ordovician trilobite genus Placoparia. Fossils and Strata, No. 4, pp. 87-95. PIs. 1-3. Oslo ISSN 0300-949l. ISBN 82-00-04963-9. The species Pl. (Placoparia) cambriensis, Pl. (Coplacoparia ) tournemini and Pl. (Coplacoparia ) borni, described by Hammann (1971) from the Spanish Ordovician, are found in Brittany in formations attributed to the Llanvirn and the LIandeilo. The lateral borders of the librigenae of Pl. (Coplacoparia) tournemini and Pl. (Coplacoparia ) borni bear depressions into which the distal ends of the thoracic pleurae and the tips of the first pair of pygidial ribs come and fit during enrollment. These depressions, or coaptative structures sensu Cuenot (1919), are also to be observed in Pl. (Placoparia) zippei and Pl. (Hawleia) grandis, from the Ordovician of Bohemia. However, in the species tournemini and borni, additional depressions appear on the anterior cephalic border, and the coaptations evolve towards an increasing complexity. From Pl. (Placoparia) cambriensis, an ancestrai form with a wide geographic distribution, two distinct populations se em to have individu· alised by a process of allopatric speciation; one of these, probably neotenous, is represented by Pl. (Coplacoparia ) tournemini (Massif Armoricain and Iberian Peninsula), the other by Pl. (Placoparia ) zippei (Bohemia). Geo graphic isolation may be indirectly responsible for the appearance of new coaptative devices. jean-Louis Henry, Laboratoire de Paleontologie et de Stratigraphie, Institut de Geologie de l'Universite, B.P. -
001-012 Primeras Páginas
PUBLICACIONES DEL INSTITUTO GEOLÓGICO Y MINERO DE ESPAÑA Serie: CUADERNOS DEL MUSEO GEOMINERO. Nº 9 ADVANCES IN TRILOBITE RESEARCH ADVANCES IN TRILOBITE RESEARCH IN ADVANCES ADVANCES IN TRILOBITE RESEARCH IN ADVANCES planeta tierra Editors: I. Rábano, R. Gozalo and Ciencias de la Tierra para la Sociedad D. García-Bellido 9 788478 407590 MINISTERIO MINISTERIO DE CIENCIA DE CIENCIA E INNOVACIÓN E INNOVACIÓN ADVANCES IN TRILOBITE RESEARCH Editors: I. Rábano, R. Gozalo and D. García-Bellido Instituto Geológico y Minero de España Madrid, 2008 Serie: CUADERNOS DEL MUSEO GEOMINERO, Nº 9 INTERNATIONAL TRILOBITE CONFERENCE (4. 2008. Toledo) Advances in trilobite research: Fourth International Trilobite Conference, Toledo, June,16-24, 2008 / I. Rábano, R. Gozalo and D. García-Bellido, eds.- Madrid: Instituto Geológico y Minero de España, 2008. 448 pgs; ils; 24 cm .- (Cuadernos del Museo Geominero; 9) ISBN 978-84-7840-759-0 1. Fauna trilobites. 2. Congreso. I. Instituto Geológico y Minero de España, ed. II. Rábano,I., ed. III Gozalo, R., ed. IV. García-Bellido, D., ed. 562 All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system now known or to be invented, without permission in writing from the publisher. References to this volume: It is suggested that either of the following alternatives should be used for future bibliographic references to the whole or part of this volume: Rábano, I., Gozalo, R. and García-Bellido, D. (eds.) 2008. Advances in trilobite research. Cuadernos del Museo Geominero, 9. -
Palynology of the Middle Ordovician Hawaz Formation in the Murzuq Basin, South-West Libya
This is a repository copy of Palynology of the Middle Ordovician Hawaz Formation in the Murzuq Basin, south-west Libya. White Rose Research Online URL for this paper: http://eprints.whiterose.ac.uk/125997/ Version: Accepted Version Article: Abuhmida, F.H. and Wellman, C.H. (2017) Palynology of the Middle Ordovician Hawaz Formation in the Murzuq Basin, south-west Libya. Palynology, 41. pp. 31-56. ISSN 0191-6122 https://doi.org/10.1080/01916122.2017.1356393 Reuse Items deposited in White Rose Research Online are protected by copyright, with all rights reserved unless indicated otherwise. They may be downloaded and/or printed for private study, or other acts as permitted by national copyright laws. The publisher or other rights holders may allow further reproduction and re-use of the full text version. This is indicated by the licence information on the White Rose Research Online record for the item. Takedown If you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing [email protected] including the URL of the record and the reason for the withdrawal request. [email protected] https://eprints.whiterose.ac.uk/ Palynology of the Middle Ordovician Hawaz Formation in the Murzuq Basin, southwest Libya Faisal H. Abuhmidaa*, Charles H. Wellmanb aLibyan Petroleum Institute, Tripoli, Libya P.O. Box 6431, bUniversity of Sheffield, Department of Animal and Plant Sciences, Alfred Denny Building, Western Bank, Sheffield, S10 2TN, UK Twenty nine core and seven cuttings samples were collected from two boreholes penetrating the Middle Ordovician Hawaz Formation in the Murzuq Basin, southwest Libya. -
Catalog of Type Specimens of Invertebrate Fossils: Cono- Donta
% {I V 0> % rF h y Catalog of Type Specimens Compiled Frederick J. Collier of Invertebrate Fossils: Conodonta SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY NUMBER 9 SERIAL PUBLICATIONS OF THE SMITHSONIAN INSTITUTION The emphasis upon publications as a means of diffusing knowledge was expressed by the first Secretary of the Smithsonian Institution. In his formal plan for the Insti tution, Joseph Henry articulated a program that included the following statement: "It is proposed to publish a series of reports, giving an account of the new discoveries in science, and of the changes made from year to year in all branches of knowledge." This keynote of basic research has been adhered to over the years in the issuance of thousands of titles in serial publications under the Smithsonian imprint, com mencing with Smithsonian Contributions to Knowledge in 1848 and continuing with the following active series: Smithsonian Annals of Flight Smithsonian Contributions to Anthropology Smithsonian Contributions to Astrophysics Smithsonian Contributions to Botany Smithsonian Contributions to the Earth Sciences Smithsonian Contributions to Paleobiology Smithsonian Contributions to Zoology Smithsonian Studies in History and Technology In these series, the Institution publishes original articles and monographs dealing with the research and collections of its several museums and offices and of profes sional colleagues at other institutions of learning. These papers report newly acquired facts, synoptic interpretations of data, or original theory in specialized fields. These publications are distributed by mailing lists to libraries, laboratories, and other in terested institutions and specialists throughout the world. Individual copies may be obtained from the Smithsonian Institution Press as long as stocks are available. -
Lee-Riding-2018.Pdf
Earth-Science Reviews 181 (2018) 98–121 Contents lists available at ScienceDirect Earth-Science Reviews journal homepage: www.elsevier.com/locate/earscirev Marine oxygenation, lithistid sponges, and the early history of Paleozoic T skeletal reefs ⁎ Jeong-Hyun Leea, , Robert Ridingb a Department of Geology and Earth Environmental Sciences, Chungnam National University, Daejeon 34134, Republic of Korea b Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996, USA ARTICLE INFO ABSTRACT Keywords: Microbial carbonates were major components of early Paleozoic reefs until coral-stromatoporoid-bryozoan reefs Cambrian appeared in the mid-Ordovician. Microbial reefs were augmented by archaeocyath sponges for ~15 Myr in the Reef gap early Cambrian, by lithistid sponges for the remaining ~25 Myr of the Cambrian, and then by lithistid, calathiid Dysoxia and pulchrilaminid sponges for the first ~25 Myr of the Ordovician. The factors responsible for mid–late Hypoxia Cambrian microbial-lithistid sponge reef dominance remain unclear. Although oxygen increase appears to have Lithistid sponge-microbial reef significantly contributed to the early Cambrian ‘Explosion’ of marine animal life, it was followed by a prolonged period dominated by ‘greenhouse’ conditions, as sea-level rose and CO2 increased. The mid–late Cambrian was unusually warm, and these elevated temperatures can be expected to have lowered oxygen solubility, and to have promoted widespread thermal stratification resulting in marine dysoxia and hypoxia. Greenhouse condi- tions would also have stimulated carbonate platform development, locally further limiting shallow-water cir- culation. Low marine oxygenation has been linked to episodic extinctions of phytoplankton, trilobites and other metazoans during the mid–late Cambrian. -
Version 4.Cdr
THE GEOMAGNETIC POLARITY TIME SCALE FOR EARY PALEOZOIC: DATA AND SYNTHESE 1 2 1 Vladimir Pavlov and Yves Gallet 2 Institute of Physics of the Earth, Institut de Physique Russian Academy of Sciences INTRODUCTION EARLY CAMBRIAN: Kirschvink and LONG STANDING CONROVERSY: Constructing the Geomagnetic Polarity Time Scale (GPTS) through the geological history is of crucial importance to address Rozanov, 1984 TWO PRIMARY POLES FOR ONE SIBERIAN PLATFORM? several major issues in Earth sciences, as for instance the long-term evolution of the geodynamo. The GPTS is also an Khramov et al., 1982 important chronological tool allowing one to decipher the age and duration of various geological processes. Moreover, GPTS 509 Ma is widely used in prospecting for commercial minerals and in petroleum geology Kirschvink’s direction OR Khramov’s direction? Series Regiostage . N N The chronology of the geomagnetic polarity reversals since the Upper Jurassic is rather well known thanks to the magnetic Kirschvink and Pisarevsky anomalies recorded in the sea floor. For more ancient epochs our knowledge of the GPTS is still very fragmentary and much Rozanov, 1984 et al., 1997 more uncertain. However significant information has been obtained for several time intervals, in particular for the Triassic and the beginning of the Phanerozoic. Hirnantian Khondelen We will focus our presentation on recent developments made in the determination of the GPTS during the Early Paleozoic P-T Botoma - Toyon Botoma - Botoma - Toyon Botoma - 516 Ma (Siberia) (Cambrian and Ordovician). Siberian APWP Ashgill Epoch 2 Epoch 2 D3-C1 экватор E30° Е90° Е150° Botmoynak Dolborian (Tianshan) Late Ediacarian - Hyperactivity of the Earth magnetic field? Early Cambrian Kirschvink’s pole Early Cambrian O2-O3 Cm3-O1 Khramov’s pole S30° Moyero N Cm2 N N Low (very low?) reversal frequency (Siberia) Pavlov et al., Pavlov et al., 2018 S60° unpubl. -
ORDOVICIAN FISH from the ARABIAN PENINSULA by IVAN J
[Palaeontology, Vol. 52, Part 2, 2009, pp. 337–342] ORDOVICIAN FISH FROM THE ARABIAN PENINSULA by IVAN J. SANSOM*, C. GILES MILLER , ALAN HEWARDà,–, NEIL S. DAVIES*,**, GRAHAM A. BOOTHà, RICHARD A. FORTEY and FLORENTIN PARIS§ *Earth Sciences, University of Birmingham, Birmingham B15 2TT, UK; e-mail: [email protected] Department of Palaeontology, The Natural History Museum, London SW7 5BD, UK; e-mails: [email protected] and [email protected] àPetroleum Development Oman, Muscat, Oman; e-mail: [email protected] §Ge´osciences, Universite´ de Rennes, 35042 Rennes, France; e-mail: fl[email protected] –Present address: Petrogas E&P, Muscat, Oman; e-mail: [email protected] **Present address: Earth Sciences, Dalhousie University, Halifax, Nova Scotia B3H 3J5, Canada; e-mail: [email protected] Typescript received 25 February 2008; accepted in revised form 19 May 2008 Abstract: Over the past three decades Ordovician pteras- morphs from the Arabian margin of Gondwana. These are pidomorphs (armoured jawless fish) have been recorded among the oldest arandaspids known, and greatly extend from the fringes of the Gondwana palaeocontinent, in par- the palaeogeographical distribution of the clade around the ticular Australia and South America. These occurrences are periGondwanan margin. Their occurrence within a very dominated by arandaspid agnathans, the oldest known narrow, nearshore ecological niche suggests that similar group of vertebrates with extensive biomineralisation of Middle Ordovician palaeoenvironmental settings should be the dermoskeleton. Here we describe specimens of arandas- targeted for further sampling. pid agnathans, referable to the genus Sacabambaspis Gagnier, Blieck and Rodrigo, from the Ordovician of Key words: Ordovician, pteraspidomorphs, Gondwana pal- Oman, which represent the earliest record of pteraspido- aeocontinent, Sacabambaspis, Oman. -
A Revision and Phylogeny of Eulonchus Gerstaecker (Diptera, Acroceridae)
A peer-reviewed open-access journal ZooKeysJewelled 619: 103–146 spider (2016) flies of North America: a revision and phylogeny ofEulonchus Gerstaecker... 103 doi: 10.3897/zookeys.619.8249 RESEARCH ARTICLE http://zookeys.pensoft.net Launched to accelerate biodiversity research Jewelled spider flies of North America: a revision and phylogeny of Eulonchus Gerstaecker (Diptera, Acroceridae) Christopher J. Borkent1, Jessica P. Gillung1, Shaun L. Winterton1 1 California State Collection of Arthropods, California Department of Food and Agriculture, 3294 Mea- dowview Road, Sacramento, CA 95832, USA Corresponding author: Christopher J. Borkent ([email protected]) Academic editor: T. Dikow | Received 24 February 2016 | Accepted 2 September 2016 | Published 27 September 2016 http://zoobank.org/DEE67859-64AC-4C3F-8DF7-67A7BE1868FB Citation: Borkent CJ, Gillung JP, Winterton SL (2016) Jewelled spider flies of North America: a revision and phylogeny of Eulonchus Gerstaecker (Diptera, Acroceridae). ZooKeys 619: 103–146. doi: 10.3897/zookeys.619.8249 Abstract The spider fly genus Eulonchus Gerstaecker is found throughout the Nearctic Region. Six species are recognized and intraspecific morphological variation is documented in several species. A phylogeny of Eulonchus based on DNA sequence data of three molecular markers (COI, CAD, and 16S) is presented and relationships of species are discussed in the light of biogeography and host usage. All six species of Eulonchus are redescribed using natural language descriptions exported from a character matrix, and a key to species is presented. Lectotypes are designated for E. sapphirinus Osten Sacken, E. smaragdinus Gerstaecker, and E. tristis Loew. Keywords Antrodiaetidae, Euctenizidae, spider parasitoid, phylogeny, small-headed fly, tarantula, biodiversity, cy- bertaxonomy, Lucid Introduction Acroceridae are a small group of flies commonly known as spider flies or small-headed flies.