DOCSLIB.ORG

Syn-To Post-Rift Topographic Tectonique and Sedimentary Evolution of the West African Transform Margin Jing Ye

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Syn-To Post-Rift Topographic Tectonique and Sedimentary Evolution of the West African Transform Margin Jing Ye Syn-to post-rift topographic tectonique and sedimentary evolution of the west African transform margin Jing Ye To cite this version: Jing Ye. Syn-to post-rift topographic tectonique and sedimentary evolution of the west African transform margin. Earth Sciences. Université Paul Sabatier - Toulouse III, 2016. English. NNT : 2016TOU30218. tel-01561691 HAL Id: tel-01561691 https://tel.archives-ouvertes.fr/tel-01561691 Submitted on 13 Jul 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. 5)µ4& &OWVFEFMPCUFOUJPOEV %0$503"5%&-6/*7&34*5²%&506-064& %ÏMJWSÏQBS Université Toulouse 3 Paul Sabatier (UT3 Paul Sabatier) 1SÏTFOUÏFFUTPVUFOVFQBS Jing YE le lundi 7 novembre 2016 5JUSF Évolution Topographique, Tectonique et Sédimentaire Syn- à Post-rift de la Marge Transformante Ouest Africaine ²DPMF EPDUPSBMF et discipline ou spécialité ED SDU2E : Sciences de la Terre et des Planètes Solides 6OJUÏEFSFDIFSDIF UMR 5563 %JSFDUFVSUSJDF T EFʾÒTF Delphine ROUBY Dominique CHARDON Jury: Sébastien CARRETIER (président du jury) Gianreto MANATSCHAL (rapporteur) Dominique FRIZON DE LAMOTTE (rapporteur) Sébastien CASTELLTORT (rapporteur) Mary FORD (examinatrice) Résumé Cette thèse présente la première étude Source-to-Sink de la marge Atlantique Equatoriale africaine au Méso- Cénozoïque. Nous avons dans un premier temps produit, à partir d’une nouvelle méthode intégrant les limites d’érosion des dépôts préservés dans les bassins et leur extension initiale minimum, une nouvelle reconstruction paléogéographique et structurale couplant pour la première fois le continent ouest africain et l’Atlantique Equatoriale au cours du Méso-Cénozoïque. Ceci nous permet de suivre l’évolution depuis 200 Ma des domaines en érosion (sources) et en sédimentation (puits) à l’échelle continentale. Nous montrons en particulier qu’au Crétacé supérieur la zone correspondait à un grand bassin intracratonique Saharien qui exportaient ses sédiments à la fois vers la Téthys et vers l’Atlantique Equatoriale. La fragmentation de ce bassin a eu lieu à l’Oligocène par le soulèvement du bouclier du Hoggar qui a isolé les petits dépôt-centres résiduels actuels. Le développement de cette topographie particulière est issu de la superposition de différentes longueurs d’onde de déformation à l’échelle continentale combinant les bourrelets marginaux longeant la marge équatoriale et un bombement de type « point chaud ». Nous avons ensuite caractérisé, à partir de l’interprétation des données sismiques et des puits, la segmentation de la marge continentale équatoriale en segments transformants et divergents et l’architecture stratigraphique post-rift du prisme stratigraphique associée au Crétacé Supérieur. Nous montrons que les parties proximales (dépôts de plateforme et pente continentale) des prismes stratigraphiques du Crétacé Supérieur ne sont préservés que le long des segments divergents de la marge, et pas le long des segments transformants. Nous interprétons cette différence de préservation comme résultant de mouvements verticaux post-rift plus importants dans les domaines proximaux des segments transformants empêchant la préservation des termes proximaux des systèmes sédimentaires. La caractérisation des architectures stratigraphiques post-rifts a ensuite permis la quantification des volumes sédimentaires préservés dans ces bassins de marges passives. En parallèle, de nouvelles données de thermochronologie basse-température (AFTA et (U-Th-Sm/He sur apatite) acquises à l’Université de Glasgow sur les échantillons de trois profils perpendiculaires à la marge équatoriale ont permis de quantifier l’histoire de l’érosion et les volumes dénudés sur le domaine continental au cours du Méso-Cénozoïque. Ces données montrent que le seul événement thermique majeur enregistré correspond au refroidissement lié à la dénudation d’une topographie syn-rift le long de la marge. Le bilan d’érosion et d’accumulation montre que les ordres de grandeur des volumes dénudés et accumulés sont comparables à l’échelle de la marge équatoriale au cours du Méso-Cénozoïque. Certaines périodes (Crétacé Supérieur et depuis le Miocène Supérieur), montrent cependant un excès d’accumulation qui pourrait être associé à la remobilisation de sédiments précédemment stockés dans des bassins intracontinentaux ou sur la plateforme de la marge. Mots clés : marge passive, bassin intracratonique, rifting, source-to-sink, paléogéographie, l’Océan Atlantique Equatoriale, Afrique, bilan d’érosion, bilan d’accumulation 1 Abstract Abstract This PhD thesis presents the first source-to-sink study of the African Atlantic Equatorial margin. We established new Meso-Cenozoic paleogeographic and structural reconstructions, integrating the West African sub- continent and the Equatorial Atlantic Ocean, based on a new mapping method defining both erosion limits of preserved deposits and their minimum original extension. We show the evolution over 200 Myrs of the eroding (sources) and accumulating domains (sinks) at continental scale. We demonstrate in particular that during the Cretaceous, a large Saharan intracratonic basin was exporting sediments toward both the Tethys and the future Atlantic Equatorial Ocean. The fragmentation of this basin occurred in the Oligocene, by the growth of the Hoggar swell that isolated the present- day small residual depot-centers. The development of this specific “basin and swell” topography results from the superimposition of various deformation wavelength at continental scale combining a marginal upwarp along the equatorial margin and a hot spot swell. We then characterized, from the interpretation of seismic data and well logs, the segmentation of the Equatorial Atlantic passive margin and the stratigraphic architecture of the post-rift Upper Cretaceous sedimentary wedge. We show that the proximal parts of the Late Cretaceous sedimentary wedge are only preserved along divergent segments of the margin and not along transform segments. We interpret this differential preservation as the result of a greater uplift, during the early post-rift, in the proximal parts of the transform segments preventing the preservation of the proximal terms of the sedimentary systems. The transform segments are associated with narrow necking zone, resulting in greater flexural uplift than divergent segments showing wider necking zones, in particular during the early post-rift. The characterization of the stratigraphic architecture of the post-rift sedimentary wedge then allowed for the quantification of accumulation history in the passive margin basins. New low-temperature thermochronological data (AFTA and Apatite (U-Th-Sm)/He) acquired at the University of Glasgow on the samples of three regional transects perpendicular to the margin allowed for the quantification of the denudation history and eroded volume on the continental domain. These data shows that the major thermal event recorded by those samples is the cooling phase related to the erosion of a rift-related topography along the margin. Erosion and accumulation budgets fall within the same order of magnitude. During some given periods (Late Cretaceous and since the Late Miocene), excess in accumulation may be associated with the reworking of sediments previously stored within intracontinental basins or on the shelf of the margin. Key words: passive margin, intracratonic basin, rifting, source-to-sink, paleogeography, Atlantic Equatorial Ocean, Africa, erosion budget, accumulation budget 2 Table of Contents Table of Contents RESUME....................................................................................................................................1 ABSTRACT.................................................................................................................................2 TABLEOFCONTENTS.................................................................................................................3 REMERCIEMENTS......................................................................................................................7 LISTOFFIGURES........................................................................................................................8 LISTOFTABLES........................................................................................................................13 INTRODUCTION.......................................................................................................................14 CHAPTER1: TRANSFORMMARGINS:ASHORTREVIEW.........................................................18 1.1. PASSIVEMARGINCLASSIFICATION:RIFTEDVSTRANSFORMMARGINS......................19 1.2. GEODYNAMICMODELOFTRANSFORMMARGINS.......................................................22 1.3. EQUATORIALATLANTICTRANSFORMMARGINSOFWESTAFRICA..............................24 1.3.1. MarginSegmentation...............................................................................................24 1.3.2. IvoryCoastGhanaTransformMargin......................................................................26 CHAPTER2: CONTEXTEGEOLOGIQUEDEL’AFRIQUEDEL’OUEST...........................................30
Load more

Recommended publications
  • AJST) Science and Engineering Series Vol
    African Journal of Science and Technology (AJST) Science and Engineering Series Vol. 4, No. 2, pp. 80-89 ISOTOPE AND GEOCHEMICAL CHARACTERIZATION OF SURFACE AND SUBSURFACE WATERS IN THE SEMI-ARID SOKOTO BASIN, NIGERIA S.M.A. Adelana1, P.I. Olasehinde1 and P.Vrbka2 1Department of Geology & Mineral Sciences, University of Ilorin, P.M.B. 1515, Ilorin, Kwara State, Nigeria. 2Kaupstrasse 37, Germany (formerly Geology Institute, Technical University Darmstadt, Germany). ABSTRACT:- Stable isotopes and geochemical studies have been applied in the investigation of groundwater resources in Sokoto Basin, northwestern Nigeria. Generally, the characteristic hydrochemical classification in the study area is calcium-alkali-bicarbonate. Surface waters are characterized by alkali-calcium-bicarbonate while groundwater is of Ca-Mg-HCO3. The plot of δ18O versus δ2H shows that five isotopic groups can be distinguished. Group I-III is of groundwater origin while group IV and V represent surface water. A combination of the hydrochemical and isotope data (14C, 13C and 3H) reveals the Sokoto basin aquifers generally contains good quality groundwater of Holocene age (100 to 10,000 years BP). Keywords: stable isotopes, geochemical characterization, groundwater, Sokoto Basin. INTRODUCTION condition by one kilometre yearly into northern Nigeria threatens agriculture. It is in the light of this that the Northwestern Nigeria is a region with great potential for Federal government of Nigeria under a joint project with future large-scale economic development due to warm the International Atomic and Energy Agency, Vienna has temperatures and bountiful resources; including thermal planned a number of irrigation schemes in order to energy, farmlands and minerals. Water resources data in increase agricultural activities in the area to two planting this area, as far back as the 60s, are available in literature seasons, thereby boosting food production.
    [Show full text]
  • Bedrock Geology Glossary from the Roadside Geology of Minnesota, Richard W
    Minnesota Bedrock Geology Glossary From the Roadside Geology of Minnesota, Richard W. Ojakangas Sedimentary Rock Types in Minnesota Rocks that formed from the consolidation of loose sediment Conglomerate: A coarse-grained sedimentary rock composed of pebbles, cobbles, or boul- ders set in a fine-grained matrix of silt and sand. Dolostone: A sedimentary rock composed of the mineral dolomite, a calcium magnesium car- bonate. Graywacke: A sedimentary rock made primarily of mud and sand, often deposited by turbidi- ty currents. Iron-formation: A thinly bedded sedimentary rock containing more than 15 percent iron. Limestone: A sedimentary rock composed of calcium carbonate. Mudstone: A sedimentary rock composed of mud. Sandstone: A sedimentary rock made primarily of sand. Shale: A deposit of clay, silt, or mud solidified into more or less a solid rock. Siltstone: A sedimentary rock made primarily of sand. Igneous and Volcanic Rock Types in Minnesota Rocks that solidified from cooling of molten magma Basalt: A black or dark grey volcanic rock that consists mainly of microscopic crystals of pla- gioclase feldspar, pyroxene, and perhaps olivine. Diorite: A plutonic igneous rock intermediate in composition between granite and gabbro. Gabbro: A dark igneous rock consisting mainly of plagioclase and pyroxene in crystals large enough to see with a simple magnifier. Gabbro has the same composition as basalt but contains much larger mineral grains because it cooled at depth over a longer period of time. Granite: An igneous rock composed mostly of orthoclase feldspar and quartz in grains large enough to see without using a magnifier. Most granites also contain mica and amphibole Rhyolite: A felsic (light-colored) volcanic rock, the extrusive equivalent of granite.
    [Show full text]
  • Callovian and Tithonian Paleogeography Legend (.Pdf)
    CALLOVIAN AND TITHONIAN AaTa Aaiun-Tarfay a Basin EVB East Venezuela Basin Mar Mardin SBet Subbetic Adha Adhami Ev ia Ev ia MarB Marmarica Basin SuBu Subbucov inian PALEOGEOGRAPHY Adri Adriatic Ex Li Ex ternal Ligurian Mars Marseille SuDa Susuz Dag LEGEND Akse Akseki Ex Ri Ex ternal Rif MAt Middle Atlas SuGe Supra-Getic Alda Aldama Ex Su Ex ternal Subetic MaU May a Uplift SuMo Supramonte Almo Almopias Ex u Ex uma MazP Mazagan Plateau Tab Tabriz Author: Caroline Wilhem Ana Anamas Fat Fatric Mec Mecsek Taba Tabas University of Lausanne - Institute of Earth Sciences Ani Anina FCB Flemish Cap Basin MC Massif Central Tac Tacchi Sheet 3 (3 sheets: 2 maps + legend; explanatory text) Ann Annecy Flor Florida Med Medv elica TadB Taoudeni Basin Anta Antaly a FoAm Foz do Amazonas Basin Mel Meliata Tahu Tahue Apu Apulia Fran Francardo Men Menderes Tal Talesh Aqui Aquitaine Basin Fri Friuli Meri Merida TaMi Tampica-Misant Basina Argo Argolis Gab Gabrov o Mese Meseta TanA Tanaulipas Arch PALEOENVIRONMENTS Armo Armorica GalB Galicia Bank MeSu Median Subbetic TaOr Talea Ori Ask Askipion Gav Gav roro Mig Migdhalista Tat Tatric Exposed land Atla Atlas GBB Grand Banks Basin Mir Mirdita Teh Tehran GeBB Georges Bank Basin Fluviodeltaic environment BaCa Baja California Mist Mistah Terek Terek BaDa Barla Dag GCau Great Caucasus Mix Mix teca TeT Tellian Trough Evaporitic platform Bade Badenli Geme Gemeric Mo Mostar Theo Theokafta Baju Bajuv aric Gen Genev a MoeP Moesian Platform TimB Timimoun Basin Terrigenous shelf and shallow basin Bako Bakony Gere Gerecse Monc
    [Show full text]
  • Oblique Rifting of the Equatorial Atlantic: Why There Is No Saharan Atlantic Ocean
    Originally published as: Heine, C., Brune, S. (2014 online): Oblique rifting of the Equatorial Atlantic: Why there is no Saharan Atlantic Ocean. – Geology 10.1130/G35082.1. Oblique rifting of the Equatorial Atlantic: Why there is no Saharan Atlantic Ocean 1 2,1 Christian Heine , Sascha Brune 1 EarthByte Group, School of Geosciences, The University of Sydney, NSW 2006, Australia 2 Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Section 2.5, Geodynamic Modelling, Potsdam, Germany ABSTRACT Rifting between large continental plates results in either continental breakup and the formation of conjugate passive margins or rift abandonment and a set of aborted rift basins. The driving mechanisms behind “successful” or “failed” rifting have so far never been scrutinized by joint kinematic and forward numerical modelling. We analyse the Early Cretaceous extension between Africa and South America which was preceded by about 20-30 Myrs of extensive rifting prior to the final separation between the two plates. While the South and Atlantic conjugate margins continued into seafloor spreading mode, forming the Atlantic ocean basin, Cretaceous-aged African intraplate rifts eventually “failed” soon after South America broke up from Africa. We address the spatio-temporal dynamics of rifting in domains by comparing a new plate kinematic model for the South Atlantic and 3D forward rift models. This joint approach elucidates (1) the dynamic competition of Atlantic and extensional systems, (2) two stage kinematics of the South Atlantic rift system, and (3) the acceleration of the South American plate prior to final break-up. We suggest that obliquity the success of the Equatorial Atlantic rift, ultimately prohibiting the formation of a “Saharan Atlantic Ocean” in the Early Cretaceous, and exerting a primary control on the increase in observed extensional velocities between the South American and African plates.
    [Show full text]
  • Durham Research Online
    Durham Research Online Deposited in DRO: 13 April 2015 Version of attached le: Published Version Peer-review status of attached le: Peer-reviewed Citation for published item: Kaislaniemi, L. and van Hunen, J. (2014) 'Dynamics of lithospheric thinning and mantle melting by edge-driven convection : application to Moroccan Atlas mountains.', Geochemistry, geophysics, geosystems., 15 (8). pp. 3175-3189. Further information on publisher's website: http://dx.doi.org/10.1002/2014GC005414 Publisher's copyright statement: c 2014. The Authors. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modications or adaptations are made. Additional information: Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full DRO policy for further details. Durham University Library, Stockton Road, Durham DH1 3LY, United Kingdom Tel : +44 (0)191 334 3042 | Fax : +44 (0)191 334 2971 https://dro.dur.ac.uk PUBLICATIONS Geochemistry,
    [Show full text]
  • Continental Complexities: a Multidisciplinary Introduction to Africa
    Continental Complexities A Multidisciplinary Introduction to Africa By Dr. Ibigbolade Simon Aderibigbe and Dr. Akinloye Ojo Included in this preview: • Table of Contents • Chapter 1 & 2 For additional information on adopting this book for your class, please contact us at 800.200.3908 x501 or via e-mail at [email protected] Dpoujofoubm!Dpnqmfyjujft A MULTIDISCIPLINARY INTRODUCTION TO AFRICA Revised Edition Edited by Ibigbolade Aderibigbe and Akinloye Ojo University of Georgia Bassim Hamadeh, CEO and Publisher Christopher Foster, General Vice President Michael Simpson, Vice President of Acquisitions Jessica Knott, Managing Editor Kevin Fahey, Cognella Marketing Manager Jess Busch, Senior Graphic Designer Zina Craft , Acquisitions Editor Jamie Giganti, Project Editor Brian Fahey, Licensing Associate Copyright © 2013 by Cognella, Inc. All rights reserved. No part of this publication may be reprinted, reproduced, transmitted, or utilized in any form or by any electronic, mechanical, or other means, now known or hereaft er invented, including photocopying, microfi lming, and recording, or in any information retrieval system without the written permission of Cognella, Inc. First published in the United States of America in 2013 by Cognella, Inc. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identifi cation and explanation without intent to infringe. Printed in the United States of America ISBN: 978-1-62131-133-1 (pbk) Contents The Study of Africa: An Introduction 1 Ibigbolade Aderibigbe
    [Show full text]
  • Geologic Map and Digital Database of the Cougar Buttes 7.5′ Quadrangle, San Bernardino County, California
    science for a changing world U. S. DEPARTMENT OF THE INTERIOR OPEN-FILE REPORT U. S. GEOLOGICAL SURVEY 00-175 GEOLOGIC MAP AND DIGITAL DATABASE OF THE COUGAR BUTTES 7.5′ QUADRANGLE, SAN BERNARDINO COUNTY, CALIFORNIA Version 1.0 SUMMARY PAMPHLET: LATE CENOZOIC DEPOSITS OF THE COUGAR BUTTES 7.5′ QUADRANGLE, SAN BERNARDINO COUNTY, CALIFORNIA By Robert E. Powell1 and Jonathan C. Matti2 2000 Prepared in cooperation with Mojave Water Agency California Division of Mines and Geology This database is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. U.S. Geological Survey 1 904 W. Riverside Avenue, Spokane, WA 99201-1087 2 520 N. Park Avenue, Tucson, AZ 85719 Open-File Report 00-175, The Geologic Map and Digital Database of the Cougar Buttes 7.5' Quadrangle, San Bernardino County, California, and this summary pamphlet have been approved for release and publication by the Director of the U.S. Geological Survey. The geologic map, digital database, and summary pamphlet have been subjected to rigorous review and are a substantially complete representation of the current state of knowledge concerning the geology of the quadrangle, although the USGS reserves the right to revise the data pursuant to further analysis and review. This Open-File Report is released on the condition that neither the USGS nor the United States Government may be held responsible for any damages resulting from its authorized or unauthorized use.
    [Show full text]
  • Sediment and Sedimentary Rocks
    Sediment and sedimentary rocks • Sediment • From sediments to sedimentary rocks (transportation, deposition, preservation and lithification) • Types of sedimentary rocks (clastic, chemical and organic) • Sedimentary structures (bedding, cross-bedding, graded bedding, mud cracks, ripple marks) • Interpretation of sedimentary rocks Sediment • Sediment - loose, solid particles originating from: – Weathering and erosion of pre- existing rocks – Chemical precipitation from solution, including secretion by organisms in water Relationship to Earth’s Systems • Atmosphere – Most sediments produced by weathering in air – Sand and dust transported by wind • Hydrosphere – Water is a primary agent in sediment production, transportation, deposition, cementation, and formation of sedimentary rocks • Biosphere – Oil , the product of partial decay of organic materials , is found in sedimentary rocks Sediment • Classified by particle size – Boulder - >256 mm – Cobble - 64 to 256 mm – Pebble - 2 to 64 mm – Sand - 1/16 to 2 mm – Silt - 1/256 to 1/16 mm – Clay - <1/256 mm From Sediment to Sedimentary Rock • Transportation – Movement of sediment away from its source, typically by water, wind, or ice – Rounding of particles occurs due to abrasion during transport – Sorting occurs as sediment is separated according to grain size by transport agents, especially running water – Sediment size decreases with increased transport distance From Sediment to Sedimentary Rock • Deposition – Settling and coming to rest of transported material – Accumulation of chemical
    [Show full text]
  • Taoudeni Basin Report
    Integrated and Sustainable Management of Shared Aquifer Systems and Basins of the Sahel Region RAF/7/011 TAOUDENI BASIN 2017 INTEGRATED AND SUSTAINABLE MANAGEMENT OF SHARED AQUIFER SYSTEMS AND BASINS OF THE SAHEL REGION EDITORIAL NOTE This is not an official publication of the International Atomic Energy Agency (IAEA). The content has not undergone an official review by the IAEA. The views expressed do not necessarily reflect those of the IAEA or its Member States. The use of particular designations of countries or territories does not imply any judgement by the IAEA as to the legal status of such countries or territories, or their authorities and institutions, or of the delimitation of their boundaries. The mention of names of specific companies or products (whether or not indicated as registered) does not imply any intention to infringe proprietary rights, nor should it be construed as an endorsement or recommendation on the part of the IAEA. INTEGRATED AND SUSTAINABLE MANAGEMENT OF SHARED AQUIFER SYSTEMS AND BASINS OF THE SAHEL REGION REPORT OF THE IAEA-SUPPORTED REGIONAL TECHNICAL COOPERATION PROJECT RAF/7/011 TAOUDENI BASIN COUNTERPARTS: Mr Adnane Souffi MOULLA (Algeria) Mr Abdelwaheb SMATI (Algeria) Ms Ratoussian Aline KABORE KOMI (Burkina Faso) Mr Alphonse GALBANE (Burkina Faso) Mr Sidi KONE (Mali) Mr Aly THIAM (Mali) Mr Brahim Labatt HMEYADE (Mauritania) Mr Sidi Haiba BACAR (Mauritania) EXPERT: Mr Jean Denis TAUPIN (France) Reproduced by the IAEA Vienna, Austria, 2017 INTEGRATED AND SUSTAINABLE MANAGEMENT OF SHARED AQUIFER SYSTEMS AND BASINS OF THE SAHEL REGION INTEGRATED AND SUSTAINABLE MANAGEMENT OF SHARED AQUIFER SYSTEMS AND BASINS OF THE SAHEL REGION Table of Contents 1.
    [Show full text]
  • Part 629 – Glossary of Landform and Geologic Terms
    Title 430 – National Soil Survey Handbook Part 629 – Glossary of Landform and Geologic Terms Subpart A – General Information 629.0 Definition and Purpose This glossary provides the NCSS soil survey program, soil scientists, and natural resource specialists with landform, geologic, and related terms and their definitions to— (1) Improve soil landscape description with a standard, single source landform and geologic glossary. (2) Enhance geomorphic content and clarity of soil map unit descriptions by use of accurate, defined terms. (3) Establish consistent geomorphic term usage in soil science and the National Cooperative Soil Survey (NCSS). (4) Provide standard geomorphic definitions for databases and soil survey technical publications. (5) Train soil scientists and related professionals in soils as landscape and geomorphic entities. 629.1 Responsibilities This glossary serves as the official NCSS reference for landform, geologic, and related terms. The staff of the National Soil Survey Center, located in Lincoln, NE, is responsible for maintaining and updating this glossary. Soil Science Division staff and NCSS participants are encouraged to propose additions and changes to the glossary for use in pedon descriptions, soil map unit descriptions, and soil survey publications. The Glossary of Geology (GG, 2005) serves as a major source for many glossary terms. The American Geologic Institute (AGI) granted the USDA Natural Resources Conservation Service (formerly the Soil Conservation Service) permission (in letters dated September 11, 1985, and September 22, 1993) to use existing definitions. Sources of, and modifications to, original definitions are explained immediately below. 629.2 Definitions A. Reference Codes Sources from which definitions were taken, whole or in part, are identified by a code (e.g., GG) following each definition.
    [Show full text]
  • Pan-African Orogeny 1
    Encyclopedia 0f Geology (2004), vol. 1, Elsevier, Amsterdam AFRICA/Pan-African Orogeny 1 Contents Pan-African Orogeny North African Phanerozoic Rift Valley Within the Pan-African domains, two broad types of Pan-African Orogeny orogenic or mobile belts can be distinguished. One type consists predominantly of Neoproterozoic supracrustal and magmatic assemblages, many of juvenile (mantle- A Kröner, Universität Mainz, Mainz, Germany R J Stern, University of Texas-Dallas, Richardson derived) origin, with structural and metamorphic his- TX, USA tories that are similar to those in Phanerozoic collision and accretion belts. These belts expose upper to middle O 2005, Elsevier Ltd. All Rights Reserved. crustal levels and contain diagnostic features such as ophiolites, subduction- or collision-related granitoids, lntroduction island-arc or passive continental margin assemblages as well as exotic terranes that permit reconstruction of The term 'Pan-African' was coined by WQ Kennedy in their evolution in Phanerozoic-style plate tectonic scen- 1964 on the basis of an assessment of available Rb-Sr arios. Such belts include the Arabian-Nubian shield of and K-Ar ages in Africa. The Pan-African was inter- Arabia and north-east Africa (Figure 2), the Damara- preted as a tectono-thermal event, some 500 Ma ago, Kaoko-Gariep Belt and Lufilian Arc of south-central during which a number of mobile belts formed, sur- and south-western Africa, the West Congo Belt of rounding older cratons. The concept was then extended Angola and Congo Republic, the Trans-Sahara Belt of to the Gondwana continents (Figure 1) although West Africa, and the Rokelide and Mauretanian belts regional names were proposed such as Brasiliano along the western Part of the West African Craton for South America, Adelaidean for Australia, and (Figure 1).
    [Show full text]
  • Towards Interactive Global Paleogeographic Maps, New Reconstructions at 60, 40 and 20 Ma
    Earth-Science Reviews 214 (2021) 103508 Contents lists available at ScienceDirect Earth-Science Reviews journal homepage: www.elsevier.com/locate/earscirev Towards interactive global paleogeographic maps, new reconstructions at 60, 40 and 20 Ma F. Poblete a,b,*, G. Dupont-Nivet a,c, A. Licht d, D.J.J. van Hinsbergen e, P. Roperch a, M. G. Mihalynuk f, S.T. Johnston g, F. Guillocheau a, G. Baby a, F. Fluteau h, C. Robin a, T.J. M. van der Linden e,i, D. Ruiz c, M.L.J. Baatsen j a G´eosciences Rennes, UMR CNRS 6118, Rennes, 35042 Rennes Cedex, France b Departamento de Geología, Facultad de Ciencias Físicas y Matematicas,´ Universidad de Chile, Chile c Universitat¨ Potsdam, Institute of Geoscience, 14476 Potsdam, Germany d Centre Europ´een de Recherche et d’Enseignement des G´eosciences de l’Environnement (Cerege), UMR CNRS 7330, 13545 Aix-en-Provence, France e Department of Earth Sciences, Utrecht University, Princetonlaan 8a, 3584 CB, Utrecht, the Netherlands f British Columbia Geological Survey, Vancouver, Canada g Department of Earth and Atmospheric Sciences, University of Alberta, Canada h Universit´e de Paris, Institut de physique du globe de Paris, CNRS, F-75005 Paris, France i Thomas van der Linden – LinGeo, Berlin, Germany j IMAU, Utrecht University, Princetonplein 5, 3584CC Utrecht, the Netherlands ARTICLE INFO ABSTRACT Keywords: Paleogeographic maps are essential tools for understanding Earth system dynamics. They provide boundary Paleogeographic maps conditions for climate and geodynamic modelling, for analysing surface processes and biotic interactions. Paleoelevation However, the temporal and spatial distribution of key features such as seaways and mountain belts that govern Cenozoic climate changes and biotic interchange differ between various paleogeographies that require regular updates Eocene-Oligocene transition with new data and models.
    [Show full text]