Structure and Geological History of the Congo Basin: an Integrated Interpretation of Gravity, Magnetic and Reflection Seismic Data E
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Regional Sources of Precipitation in the Ethiopian Highlands Regionala Källor Till Nederbörden I Det Etiopiska Höglandet
Independent Project at the Department of Earth Sciences Självständigt arbete vid Institutionen för geovetenskaper 2015: 2 Regional Sources of Precipitation in the Ethiopian Highlands Regionala källor till nederbörden i det Etiopiska höglandet Elnaz Ashkriz DEPARTMENT OF EARTH SCIENCES INSTITUTIONEN FÖR GEOVETENSKAPER Independent Project at the Department of Earth Sciences Självständigt arbete vid Institutionen för geovetenskaper 2015: 2 Regional Sources of Precipitation in the Ethiopian Highlands Regionala källor till nederbörden i det Etiopiska höglandet Elnaz Ashkriz Copyright © Elnaz Ashkriz and the Department of Earth Sciences, Uppsala University Published at Department of Earth Sciences, Uppsala University (www.geo.uu.se), Uppsala, 2015 Sammanfattning Regionala källor till nederbörden i det Etiopiska höglandet Elnaz Ashkriz Denna uppsats undersöker ursprunget till den stora mängd nederbörd som faller i det etiopiska höglandet. Med Moisture transport into the Ethiopian Highlands av Ellen Viste och Asgeir Sorteberg (2011) som grund syftar denna uppsats till att jämföra samma data men genom att titta på ett mycket kortare intervall för att se vad som försummas när undersökningar på större skalor utförs. Medan undersökningen av Viste och Sorteberg (2011) fokuserar på de två regnrikaste månaderna, juli och augusti under elva år, 1998-2008, så fokuserar denna uppsats enbart på juli år 2008. Syftet med denna uppsats var att se vart nederbörden till det Etiopiska höglandet kommer ifrån under juli månad 2008. För att undersöka detta så har man valt att titta på parametrar såsom horisontell- och vertikal vindriktning på olika höjder samt fukt- innehållet i dessa vindar. Som grund för undersökningen så har denna uppsats, likt Vistes och Sortebergs, använt ERA-Interim data. -
Record of the Angola Portion of the Congo Craton: Newly Dated Magmatic Events at 1500 and 1110 Ma and Implications for Nuna (Columbia) Supercontinent Reconstructions
NOTICE: This is the author’s version of a work that was accepted for publication in Precambrian Research. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Precambrian Research, Vol. 230 (2013). doi: 10.1016/j.precamres.2013.01.010 Accepted Manuscript Title: Mesoproterozoic intraplate magmatic ‘barcode’ record of the Angola portion of the Congo craton: newly dated magmatic events at 1500 and 1110 Ma and implications for Nuna (Columbia) supercontinent reconstructions Authors: Richard E. Ernst, Eurico Pereira, Michael A. Hamilton, Sergei A. Pisarevsky, Jose´ Rodriques, Colombo C.G. Tassinari, Wilson Teixeira, Vitoria´ Van-Dunem PII: S0301-9268(13)00011-9 DOI: doi:10.1016/j.precamres.2013.01.010 Reference: PRECAM 3703 To appear in: Precambrian Research Received date: 24-7-2012 Revised date: 26-11-2012 Accepted date: 3-1-2013 Please cite this article as: Ernst, R.E., Pereira, E., Pisarevsky, S.A., Rodriques, J., Tassinari, C.C.G., Teixeira, W., Van-Dunem, V., Mesoproterozoic intraplate magmatic ‘barcode’ record of the Angola portion of the Congo craton: newly dated magmatic events at 1500 and 1110 Ma and implications for Nuna (Columbia) supercontinent reconstructions, Precambrian Research (2010), doi:10.1016/j.precamres.2013.01.010 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. -
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 -
Empty Forests, Empty Stomachs? Bushmeat and Livelihoods in the Congo and Amazon Basins
International Forestry Review Vol.13(3), 2011 355 Empty forests, empty stomachs? Bushmeat and livelihoods in the Congo and Amazon Basins R. NASI1, A. TABER1 and N. VAN VLIET2 1Center for International Forestry Research (CIFOR), Jalan CIFOR, Situ Gede, Sindang Barang, Bogor 16680, Indonesia 2Department of Geography and Geology, University of Copenhagen, Oster Voldgade 10, 1350 Copenhagen K, Denmark Email: [email protected], [email protected] and [email protected] SUMMARY Protein from forest wildlife is crucial to rural food security and livelihoods across the tropics. The harvest of animals such as tapir, duikers, deer, pigs, peccaries, primates and larger rodents, birds and reptiles provides benefits to local people worth millions of US$ annually and represents around 6 million tonnes of animals extracted yearly. Vulnerability to hunting varies, with some species sustaining populations in heavily hunted secondary habitats, while others require intact forests with minimal harvesting to maintain healthy populations. Some species or groups have been characterized as ecosystem engineers and ecological keystone species. They affect plant distribution and structure ecosystems, through seed dispersal and predation, grazing, browsing, rooting and other mechanisms. Global attention has been drawn to their loss through debates regarding bushmeat, the “empty forest” syndrome and their ecological importance. However, information on the harvest remains fragmentary, along with understanding of ecological, socioeconomic and cultural dimensions. Here we assess the consequences, both for ecosystems and local livelihoods, of the loss of these species in the Amazon and Congo basins. Keywords: bushmeat, livelihoods, forest, Amazon, Congo Forêts vides, estomacs vides? Viande de brousse et condition de vie dans les bassins du Congo et de l’Amazone. -
Permische Stegocephalen Und Reptilien Aus Texas
© Biodiversity Heritage Library, http://www.biodiversitylibrary.org/; www.zobodat.at 1UN '4 1904 Permische Stegocephalen und Reptilien aus Texas von Ferdinand Broili. Einleitung. Die erfolgreichen Resultate der STERNBERG'schen Expedition nach Texas im Frühjahr 1895, die eine Menge ausgezeichneten Materials von Eryops, Dimetrodon, Labidosaurus in das Münchner palae- ontologische Museum brachte, veranlaßte den Konservator der palaeontologischen Staatssammlung, Herrn Geheimrat v. Zittel, im Jahre 1901 zum zweitenmale eine solche in die permischen Ablagerungen der dortigen Gebieten auszusenden. Auch diesmal glückte es, Herrn Ch. Steenbeeg, den ausgezeichneten Sammler von Lawrence City in Kansas für das Unternehmen zu gewinnen, und schon im Juni des gleichen Jahres befand sich derselbe inmitten seines Wirkungskreises, auf den Wi chita beds des Perm, in der Nähe der kleinen, an einer Seitenlinie der „Fort Worth and Denver Railroad" gelegenen Steppenstadt Seymour (Baylor Co.). Bei meiner Ankunft in dieser Niederlassung — mir selbst war es durch die Unterstützung der k. b. Akademie der Wissenschaften möglich gemacht, mich von Anfang bis Ende August an den Auf- sammlungen z\i beteiligen — fand ich bereits ein sehr reichhaltiges Material vor, das neben Besten von Dimetrodon, Labidosaurus, Pariotichus und anderen Theromorphen, eine vorzügliche Kollektion verschie- dener Individuen von Diplocaidus enthielt, von denen vereinzelte noch im Besitz eines großen Teiles der Wirbelsäule waren. Während meiner Anwesenheit im dortigen Gebiet erstreckte sich unsere Tätigkeit hauptsächlich auf AufSammlungen von unserem Lager aus, das wir infolge des durch große Hitze ein- getretenen Wassermangels stets unweit von Seymour zu halten gezwungen waren. Fundpunkte. Die wichtigsten Fundpunkte, an denen befriedigende Resultate erzielt wurden, finden sich bei Seymour meist in der Nähe tief eingeschnittener, in jenem Sonnner völlig trockener Bachrisse (z. -
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. -
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). -
A Fundamental Precambrian–Phanerozoic Shift in Earth's Glacial
Tectonophysics 375 (2003) 353–385 www.elsevier.com/locate/tecto A fundamental Precambrian–Phanerozoic shift in earth’s glacial style? D.A.D. Evans* Department of Geology and Geophysics, Yale University, P.O. Box 208109, 210 Whitney Avenue, New Haven, CT 06520-8109, USA Received 24 May 2002; received in revised form 25 March 2003; accepted 5 June 2003 Abstract It has recently been found that Neoproterozoic glaciogenic sediments were deposited mainly at low paleolatitudes, in marked qualitative contrast to their Pleistocene counterparts. Several competing models vie for explanation of this unusual paleoclimatic record, most notably the high-obliquity hypothesis and varying degrees of the snowball Earth scenario. The present study quantitatively compiles the global distributions of Miocene–Pleistocene glaciogenic deposits and paleomagnetically derived paleolatitudes for Late Devonian–Permian, Ordovician–Silurian, Neoproterozoic, and Paleoproterozoic glaciogenic rocks. Whereas high depositional latitudes dominate all Phanerozoic ice ages, exclusively low paleolatitudes characterize both of the major Precambrian glacial epochs. Transition between these modes occurred within a 100-My interval, precisely coeval with the Neoproterozoic–Cambrian ‘‘explosion’’ of metazoan diversity. Glaciation is much more common since 750 Ma than in the preceding sedimentary record, an observation that cannot be ascribed merely to preservation. These patterns suggest an overall cooling of Earth’s longterm climate, superimposed by developing regulatory feedbacks -
Evidence of a Permian Remagnetization in the Neoproterozoic- Cambrian Adoudounian Formation (Anti-Atlas, Morocco)
Bulletin de l’Institut Scientifique, Rabat, section Sciences de la Terre, 2012, n° 34, p. 15-28. Evidence of a Permian remagnetization in the Neoproterozoic- Cambrian Adoudounian Formation (Anti-Atlas, Morocco) Florent BOUDZOUMOU1,2, Didier VANDAMME2, Pascal AFFATON2 Jérôme GATTACCECA2, Hassane OUAZZANI3, Lakhlifi BADRA3 3 & Elmahjoub MAHJOUBI 1. Université Marien Ngouabi, Faculté des Sciences, Département de Géologie, B.P. 69, Brazzaville, Congo. e-mail : [email protected] 2. CEREGE, Université d’Aix-Marseille, CNRS, B.P. 80, Europôle Méditerranéen de l’Arbois, 13545 Aix-en-Provence Cedex 04, France. 3. Université Moulay Ismail, Faculté des Sciences, Département de Géologie, B.P. 11201 Zaitoune, Meknès, Maroc. Abstract. A paleomagnetic study was undertaken on samples collected from seven sites of the exhumed and eroded Ait-Abdallah and Kerdous antiforms in the Moroccan Anti-Atlas of the West African craton. These sites are located in the Adoudounian Formation considered as of Neoproterozoic–Cambrian age. The magnetic mineralogy is represented essentially by magnetite and titanohematite. Magnetization is carried by three components respectively of high-temperature (500-670°C), medium-temperature (350-470°C) and low- temperature (NRM-300°C). Plotted in Gondwana Apparent Polar Wander Path, the high and medium temperature components close to the Permian pole and determine Permian overprint directions. The low temperature component closes to the present day field and corresponds to the present overprint day. This study shows that Permian overprint largely affect the Anti-Atlas area. Key words: Paleomagnetism, Anti-Atlas, West-African craton, Adoudounian Formation, Neoproterozoic, Cambrian. Mise en évidence d’une ré-aimantation permienne dans la Formation Adoudounienne, d’âge Néoprotérozoïque-Cambrien (Anti- Atlas, Maroc) Résumé. -
The Making of Concessions: Traditional Authorities, Transnational
The Making of Concessions: Traditional Authorities, Transnational Capital, and Territorialized Identities in Africa By Rebecca Hardin Paper presented to the Environmental Politics Seminar UC Berkeley, April 27 2007 Draft: please do not cite, nor reproduce Note: This paper presents a framework I am developing for a book project tentatively entitled “Concessionary Cultures.” I am currently revising the project for the University of California Press series “Colonialisms.” The opportunity to benefit from the EP seminar discussion is very welcome. In developing this to date I have incurred intellectual debts to the following readers: Arun Agrawal, Susan E. Cook, Jane Guyer, Alain Karsenty, Damani Partridge, John Galaty, Nahomi Ichino, Eduardo Kohn, Nadine Naber, Devra Meuller, Abena Osseo-Assare, Lorraine Paterson, Beth Povinelli, Hugh Raffles, Jesse Ribot, Mary Steedly, Miriam Ticktin, Diana Wylie,and an anonymous reviewer for the University of California Press. The research support of McGill University, the University of Michigan, and the Harvard Academy of International and Area Studies has been crucial, 1 Nestled within the Dzanga Sangha Dense Forest Reserve and Dzanga Ndoki National Park, the small town of Bayanga is the largest settlement in that southernmost triangle of the Central African Republic (CAR) that borders Cameroon and the Republic of Congo (Brazzaville). The establishment (1988) and subsequent legislation (1991) of the Park and Reserve (which I’ll refer to at the RDS) created one of the last protected areas established in the CAR, and one of only two sizeable forest reserves in that country. Conducting research on the role of tourism and trophy hunting in the management of this protected area found me sitting one evening with a pair of professional trophy hunters over the cocktails they call “sundowners.” During their hunts with clients that week, they complained, they had found abundant evidence of poaching, and they feared that too many of the animal trophies they sought might be marred by scars from wire snares. -
Géochimie Des Black Shales Du Jurassique Supérieur De La Plate-Forme Russe
Géochimie des black shales du Jurassique supérieur de la plate-forme russe. Processus de sédimentation et de préservation de la matière organique Armelle Riboulleau To cite this version: Armelle Riboulleau. Géochimie des black shales du Jurassique supérieur de la plate-forme russe. Processus de sédimentation et de préservation de la matière organique. Géochimie. Université Pierre et Marie Curie - Paris VI, 2000. Français. tel-00006731 HAL Id: tel-00006731 https://tel.archives-ouvertes.fr/tel-00006731 Submitted on 24 Aug 2004 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. THESE de DOCTORAT de l'UNIVERSITE PARIS 6 pour obtenir le grade de DOCTEUR de l'UNIVERSITE PARIS 6 présentée par Mlle Armelle RIBOULLEAU Sujet de la thèse Géochimie des black shales du Jurassique supérieur de la plate-forme russe. Processus de sédimentation et de préservation de la matière organique soutenue le 21 Décembre 2000 devant le jury composé de : M. P. Albrecht (CNRS, Strasbourg)..........................................................Rapporteur M. P. Farrimond (Université de Newcastle) ..............................................Rapporteur M. F. Baudin (Université Paris 6) .............................................................Directeur de thèse M. J. Boulègue (Université Paris 6) ..........................................................Examinateur M. G. Gorin (Université de Genève) .........................................................Examinateur M. -
Living Under a Fluctuating Climate and a Drying Congo Basin
sustainability Article Living under a Fluctuating Climate and a Drying Congo Basin Denis Jean Sonwa 1,* , Mfochivé Oumarou Farikou 2, Gapia Martial 3 and Fiyo Losembe Félix 4 1 Center for International Forestry Research (CIFOR), Yaoundé P. O. Box 2008 Messa, Cameroon 2 Department of Earth Science, University of Yaoundé 1, Yaoundé P. O. Box 812, Cameroon; [email protected] 3 Higher Institute of Rural Development (ISDR of Mbaïki), University of Bangui, Bangui P. O. Box 1450, Central African Republic (CAR); [email protected] 4 Faculty of Renewable Natural Resources Management, University of Kisangani, Kisangani P. O. Box 2012, Democratic Republic of Congo (DRC); [email protected] * Correspondence: [email protected] Received: 22 December 2019; Accepted: 20 March 2020; Published: 7 April 2020 Abstract: Humid conditions and equatorial forest in the Congo Basin have allowed for the maintenance of significant biodiversity and carbon stock. The ecological services and products of this forest are of high importance, particularly for smallholders living in forest landscapes and watersheds. Unfortunately, in addition to deforestation and forest degradation, climate change/variability are impacting this region, including both forests and populations. We developed three case studies based on field observations in Cameroon, the Central African Republic, and the Democratic Republic of Congo, as well as information from the literature. Our key findings are: (1) the forest-related water cycle of the Congo Basin is not stable, and is gradually changing; (2) climate change is impacting the water cycle of the basin; and, (3) the slow modification of the water cycle is affecting livelihoods in the Congo Basin.