DOCSLIB.ORG

Project Uranium of Chad

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Project Uranium of Chad REPUBLIC OF CHAD Ministry of Oil ,Mines and Energy presented by: Mr. DJEDOUBOUM Emmanuel Ambroise and Mr. BRAHIM ABDERAMANE YACINE E-mail: [email protected]/[email protected] 10 -14 November ,2014/Johannesburg I. INTRODUCTION Chad is a landlocked country located in the heart of Africa, between 7 ° and 24 ° N, 13 ° and 24 ° east longitude. It has an area of 1,284,000 km2 and extends from north to south and 1900 km from east to west over 900km. It shares borders with Libya, Sudan, Niger, Nigeria, Cameroon and the Central African Republic. The major part of the country is in the form of a plain altitude between 290-320 m. Depression located SW of Faya Largeau, which represents the lowest point of the country, is about 120 m below the level of Lake Chad located in the approximate odds of 280 m. The Chad has three mountain ranges: the stage of Ouddaï east on the border with Sudan which altitudes vary between 500 and 1000 m, the central massif (Guera), which rises to 1600 m and the Tibesti north including several peaks over 3,000 m, and whose peak reaches 3415 m Emi Koussi. Fifth African country area (1.284.000km2), filled with 11,274,106 inhabitants according to the last population census in 2009 and with a mineral potential not yet developed, Chad remains to date a virgin area. II. GEOLIGICAL BAKGROUND The Chad is between the Congolese craton south, the West African craton in the west and the Nile Craton northeast. The geology consists of two main geological units: Precambrian crystalline basement and sedimentary cover. The oldest rocks (granitoid) and Precambrian metamorphic rocks are found on the outskirts of two bowls: one of Erdis, which is an extension of the Libyan Kufra basin, and Lake Chad. They suffered major orogenic events (Pan late Proterozoic: 600/650 Ma). The Chadian space can be partitioned into ten groups, from north to south. Mayo Kebbi is located south-west of the country, on the border with Cameroon. It is a region consisting of previously developed land and pleated that extend into Cameroon hills. Land recognized are varied, and folded sedimentary, metamorphic and igneous Proterozoic and Archean. This is probably the most explored and best known geologically region. The Guéra or Massif Central is a blunting of eroded base which forms a massive hill between N'Djamena and Abeche. The crystalline rocks, in particular, are poorly understood. Salamat, opposite the Central African Republic, is a very moist and rich in plant area. As for the north, the difficulties of access to the region's geology explain that remains the subject of many questions. Here is some brief geological settings Chad III.RESSOURCES OF URANIUM Uranium mineral resources of Chad are distributed in several ways throughout the territory: In the late 1940, the mapping showed the presence of uranium and thorium index of the most developers are in BET North and in Mayo Kebbi West and South. Most of these indices are associated with alkaline granites, leuco granites or syenites of Protorozoïque. There are other indications of thorium in sedimentary environment in relation to deposits from ancient regolith overhaul. Clues uranium "primary" include in the Tibesti, north Aouzou towards Yedri, ten uranium occurrences identified in the granitic basement fractures in Enneri Miski, south of Tibesti, an index located in southeastern Zouar; Finally, in the Mayo Kebbi West, madazang or surveys have to recognize the presence of pitchblende, coffinite of silicates, U-Pb. The exploration minéralisation attribute this to an overlapping area shaer zones Units Néoprotorozoïque. Clues to Thorium and sedimentary uranium are reported in the Paleocene cover: In the Cambro-Ordovician conglomerate regions Boubao, Wadi Baku (near fada); At the base of the Ordovician sandstones on the periphery of the Tibesti; GEOLOGICAL MAP OF CHAD A.URANIUM OF MADAGZANG The deposit Madagzang (Léré,Mayo Kebbi West) is best known because it has been the subject of previous studies by UNDP and the IAEA (International Atomic Energy Agency) between 1970s and 1980s these studies were supplemented by exploration Chad Mining Services Limited. The Chad Mining Services Company has completed over 170 vertical wells,22 trenches and a dozen drilling inclined concentrations vary from one well to another the greatest value is in the order of 4000ppm in wells and is 50 to 100 ppm in surface during the mapping. The deposit is estimated at 8,000,000 tons. a. Methodology: CMS works are performed from 2007 to 2010 as follows: • Airborne (airbone survey); • The mapping (mapping); • Utilization spectrometer hand and Probe • Drilling and trenching; • The sampling; • Log drilling and log trenches; • Entering data into the SABLE software IV.EXPLORATION PROSPECTS Guera at the Centre of the country, has a potential still unclear, alkaline granitic (attributed to the Pan African) Added to this is the entire province of BET(Borkou-Ennedi-Tibesti) presents a potential whatsoever in base with differentiated granites, or in training coverage, just outside the Tibesti. In particular, continental clastic formations interspersed Paleozoic paleo-fracture subméridiennes presents comparable to that of the region of the Air in Niger characteristics. From the above uranium in Chad is not explored in its entirety, it necessary to deploy the means to highlight the areas of indices which we have just discussed to better understand the subject of this deposit very helpful as energy. Maesure of concentration of Uranium of Léré WELL DRILLING SAMPLE OF CORE DRILLING HEMATISED CORE DRILLING Spectrometer Sample of core drilling MAP OF DIFFERENTS ZONES OF FAVORABILITY OF CONCENTRATION OF URANIUM Zones of high favorability zones of midlle favorability Zones of low favorability V. CONCLUSION In conclusion we can say that the Republic of Chad is a relatively landlocked territory without easy access to the sea; it is important to target the development of areas of the Massif Central; Borkou-Ennedi-Tibesti to evaluate all of the reserves and this area of uranium​​ developer little known in our country. THANK YOU FOR YOUR ATTENTION!!! .
Load more

Recommended publications
  • The Disappearance of Lake Chad: History of a Myth
    The disappearance of Lake Chad: history of a myth Géraud Magrin1 Université Paris 1 Panthéon-Sorbonne, France Abstract The article explores the hydropolitics of Lake Chad. Scientific and popular views on the fate of Lake Chad differ widely. The supposed 'disappearance' of the Lake through water abstraction and climate change is a popular myth that endures because it serves a large set of heterogeneous interests, including those supporting inter-basin water transfers. Meanwhile scientific investigations show substantial and continuing Lake level fluctuations over time, and do not support its projected disappearance. The task is to understand how the myth of the disappearing Lake has been engendered and used, by studying the discourses and the strategies of the main stakeholders involved. The Lake has been protected so far from massive water abstraction, and inter-basin transfer projects, due to the fragmentation of its political management, new security threats, and the piecemeal nature of the interests in play. Key words: Lake Chad; environmental myths; hydropolitics; political ecology; inter-basin transfers Résumé Cet article aborde le lac Tchad d’un point de vue hydropolitique. Les discours scientifique et du grand public sur l'état du lac Tchad diffèrent largement. La « disparition » supposée du lac sous l’effet des prélèvements anthropiques pour l’irrigation et du changement climatique est un mythe qui perdure car il sert un ensemble d'intérêts hétérogènes, dont ceux favorables à un projet de transfert d'eau inter-bassins. Or les recherches scientifiques montrent que le lac a toujours fluctué au cours du temps, et que les dynamiques récentes ne conduisent pas à sa disparition, si souvent annoncée.
    [Show full text]
  • Provinces De L'ennedi Ouest Et De L'ennedi Est Mars 2021
    TCHAD Provinces de l'Ennedi Ouest et de l'Ennedi Est Mars 2021 19°30'0"E 20°0'0"E 20°30'0"E 21°0'0"E 21°30'0"E 22°0'0"E 22°30'0"E 23°0'0"E 23°30'0"E 24°0'0"E Mousso Logoi Localités Tekaro Dfana Louli Ouri-Sao Chef-lieu de province Ehi Kaidou Chef-lieu de département Barkai Tohon Ouana Yangara 21°30'0"N Arasche Horama 21°30'0"N Chef-lieu de sous-préfecture Ouri Sao Angama Camp de réfugiés Enneri Tougoumchi Village vrai Borou Koultimi Ehi Ohade Ohade Infrastructures Bogore Enneri Fofoda Tire-Tacoma Centre de santé Ouaga Kourtima Gara Yasko Antenne reseau téléphonique Ergueme Ounga Gara Toukouli Kayobe Piste d'atterrissage 21°0'0"N Dohobou L I B Y E 21°0'0"N Secondaire Gara Abou Ndougay Tertiaire Tedegra Piste TIBESTI EST Limites administratives Tarou Frontière nationale Ouarou T I B E S T I Limite de province Altipiano di Gef-gef el-Chebir Limite de département 20°30'0"N 20°30'0"N Moura Gara Talehat Ehi Micha Ghere Talha Magan Bezi Yeskimi Djebel Hadid Bobodei Ehi Droussou 20°0'0"N 20°0'0"N Mare de Salem Boudou Tchige Moza Garet el Gorane Yoga Drosso Arkononno Bini Odomanga Korozo Moiounga Gara Louli Dorron Enneri Binem Dor Forria Oued Ouorchille Billinga Kossomia Doudou Siss Arkenoki Oude Bourbou Agotega Bibida Bourdounga Gouro Galkounga Fochi Bezi Kioranga Bibideme Oulemechi Arkenia Tekro 19°30'0"N Aroualli Seguerday 19°30'0"N Seger Mardakilinga Tala Amossri Kei Gara Yeskia Erdi Korko Kouroumai Ouachi Kiroma Kada Bibidozedo Adem Boeina Tordou-Emi Diendale Baisa Anissadeda Kei Douringa Kizimi Arka Erdi Fochimi Marhdogoum Amerouk Tomma
    [Show full text]
  • Journal of Conventional Weapons Destruction Chad
    Journal of Conventional Weapons Destruction Volume 10 Issue 1 The Journal of Mine Action Article 18 August 2006 Chad Country Profile Center for International Stabilization and Recovery at JMU (CISR) Follow this and additional works at: https://commons.lib.jmu.edu/cisr-journal Part of the Defense and Security Studies Commons, Emergency and Disaster Management Commons, Other Public Affairs, Public Policy and Public Administration Commons, and the Peace and Conflict Studies Commons Recommended Citation Profile, Country (2006) "Chad," Journal of Mine Action : Vol. 10 : Iss. 1 , Article 18. Available at: https://commons.lib.jmu.edu/cisr-journal/vol10/iss1/18 This Article is brought to you for free and open access by the Center for International Stabilization and Recovery at JMU Scholarly Commons. It has been accepted for inclusion in Journal of Conventional Weapons Destruction by an authorized editor of JMU Scholarly Commons. For more information, please contact [email protected]. Profile: Chad COUNTRY PROFILES points in the Borkou-Ennedi-Tibesti region. and coastal areas, swamps make demining As Egypt is a quickly developing and grow- Due to lack of funding, the MAG/UNOPS work difficult, and in the Western Desert, ing country, land will become increasing- contract ended in December 2005 and the sand dunes and wind move and conceal ly important. deminers are waiting for a new contract. The landmines/UXO.6 The aging of UXO items by Megan Wertz deployment of three EOD teams was planned makes them increasingly unsteady and prone Facing the Future [ Mine Action Information Center ] for April 1, 2006, but due to logistical prob- to detonation.
    [Show full text]
  • TCHAD : Carte De Référence Du Tibesti (Février 2018)
    TCHAD : Carte de référence du Tibesti (février 2018) 13°0'0"E 14°0'0"E 15°0'0"E 16°0'0"E 17°0'0"E 18°0'0"E 19°0'0"E 20°0'0"E 21°0'0"E 22°0'0"E 23°0'0"E Curni Ebredaa Al Malaqi Gara Kourni Guelta Mouri Idie Mezafeh Eringi Kourini Ehi Ebesoua Askinoa Biligay 23°0'0"N Tourki Dao 23°0'0"N Bissan Ehi- Bardi Kidi Sigurian Fokiri Tehia Hamadat Mouri Idie Tega Askinoa Manghini Ehi Bissoa Eke Rhoan Fokioure Garako-Karamo Fokiri Tenere Gara Mezora Ehi Mozorki Ehi Fokiri Mali Dourdoura Bir el War Tanoa Odorloptina Domasaka Gara Dohonia ⛜ Oloseri Ehi Yohobe Tiri Ennedi Sanaka Yourokali Gege Kourini Kourina Ouadoi Ennri Sanaka Nangara Ehi Kourina Ziri Goubou Ehi Araye Ehi Aray Passe de Sidi Aidao Ehi Ehi Kourizo Korizo Agala Enneri Aray Dafora Ehi Agalla Tara Oske Enneri Ehi Loga Bai Darda-Morkena Talagoum Abou Ehi Tchouhi Enneri Ache Yebige Enneri Aozou Tuzugu Tioumi-Ahinoa Enneri Kakeron Lama-Kora Gara Lakor Ehi Tchoui Ehi Doma Dougouli Tebidi Tiohodoma Tirke Enneri Sogoyi L I B YE Lemakora Ehi Chilii Bordaa Ehi Chili Koundie Ehi Tihodoma Ennedi Gudu Ennedi Gadu Eoj Wahs Yourgor-Gara Afafi Plateau Col de Mechi Taba Enneri Taar Gebel Afafi Touside-Fosma Enneri Meche Dobious Looteni Koysono Ehi Sohayi Ehi Tekoukoue Enneri Ehi Madoa Ehi Nangara Soo Ehi Ehi Dogolaga Oudji-Emi Yedri Mine Morogue Koui Ergida Elliguemi Ehi Enneri Enneri Kasa Kourea Mamadou Enneri Arabi Sao Yedri Enneri Yedri Ehi Tchedona Ehi Domor Eligemi Dogologa Chedenemia Ehi Kourea-Momodoy Asaserde Oualasena Aray Yedri Tega Taar Fodogoroa Orda Afafi Galliema Enneri Enneri Enneri Fodogoroum
    [Show full text]
  • Rising Food Insecurity Across Lake Chad Basin Humanitarian Bulletin
    Humanitarian Bulletin West and Central Africa April 2016 In this issue Lake Chad food insecurity on the rise P.1 Sahel food insecurity remains high P.3 New displacements in Côte d’Ivoire P.5 HIGHLIGHTS Ebola resurfaces in Guinea and Liberia P.6 Three million people in the Regional update on epidemics P.7 Lake Chad region are facing Sahel funding update P.8 severe food shortages. In Nigeria’s Borno and Yobe states, 800,000 people need immediate assistance. Rising food insecurity across Lake Chad Basin Clashes between herders and farmers in Côte d’Ivoire Food insecurity in the Lake Chad region, already at crisis levels, is expected to further deepen as families exhaust their last reserves and the lean season progresses. displace over 6,000 people. Between January and April, Three million people are currently facing severe food shortages. The majority of the food insecure people are in Nigeria’s north-eastern Borno and Yobe states. DRC reports 5,757 cholera cases. Ebola resurfaces for the third time in Liberia, Guinea sees its first flare-up. KEY FIGURES People 2.4M displaced in Lake Chad Basin Severely food 2.9M insecure people in Lake Chad Basin People facing 6.7M crisis level of food insecurity in the Sahel SAHEL FUNDING US $1.9 billion requested in 2016 12% funded Humanitarian Bulletin | 2 In Borno, 1.6 million Immediate emergency assistance required people are in emergency According to a joint UN multi-sectoral assessment, carried out in April, in Borno alone, some 1.6 million people are facing severe food insecurity, with more than 550,000 in phase of food insecurity.
    [Show full text]
  • Ennedi Expedition 1St – 8Th February 2022 Expedition Overview
    Ennedi Expedition 1st – 8th February 2022 Expedition Overview 1st February 2022 Radisson Blu Hotel | N’Djamena | Chad 2nd February 2022 N’Djamena to Ennedi Natural and Cultural Reserve 2nd to 8th February 2022 Explore Ennedi Natural and Cultural Reserve 1st to 8th February 2022 8th February 2022 Ennedi Expedtion Ennedi Natural and Cultural Reserve to N’Djamena 1 night Radisson Blu Hotel 4 nights Warda Camp 2 nights Mobile camp A day-to-day breakdown… 1st February 2022 - N’DJAMENA | CHAD On arrival in N’Djamena you will be met by your expedition guide, and your ground team, and road transferred to the Radisson Blu Hotel for the night. Dependent on arrival time you may want to relax in the hotel, experience the N’Djamena horseracing or enjoy relaxing sundowners overlooking the Chari river and Cameroon. 2nd February 2022 - NDJ-FADA-TERKEI | ENNEDI Today we will have an early start before heading to the airport to board our charter flight to Fada. Fada is a characteristic Saharan village and the gateway to Ennedi. On arrival in Fada we’ll meet our expedition team and complete some district formalities before heading out into the vast landscape of the Ennedi Massif. Our route to Warda camp passes a beautiful region of tassilian rock formations, tongues of sand and, in Terkey, we will visit one of the most important rock art sites in the region. After a day of adventure we arrive at Warda camp, our base for the next 3 nights. Dinner and overnight at Warda Camp. A day-to-day breakdown… 3rd February 2022 - NOHI-LABYRINTH-ARCHEI | ENNEDI Today we head out to explore the beautiful and verdant landscape of Wadi Nohi, amazing cave sites rich in paintings, the water formed Oyo labyrinth and finally the incredible wadi Archei.
    [Show full text]
  • Ennedi Expedition 2Nd – 9Th February 2021 Expedition Overview
    Ennedi Expedition 2nd – 9th February 2021 Expedition Overview 2nd February 2021 Radisson Blu Hotel | N’Djamena | Chad 3rd February 2021 N’Djamena to Ennedi National Park 3rd – 9th February 2021 Explore Ennedi National Park 2nd – 9th February 2021 9th February 2021 Ennedi Expedtion Ennedi National Park to N’Djamena 2 nights Radisson Blu Hotel 4 nights Warda Camp 2 nights Mobile camp A day-to-day breakdown… 2nd February 2021 - N’DJAMENA | CHAD On arrival in N’Djamena you will be met by your expedition guide, and your ground team, and road transferred to the Radisson Blu Hotel for the night. Dependent on arrival time you may want to relax in the hotel, experience the N’Djamena horseracing or enjoy relaxing sundowners overlooking the Chari river and Cameroon. 3rd February 2021- NDJ-FADA-TERKEI | ENNEDI Today we will have an early start before heading to the airport to board our charter flight to Fada. Fada is a characteristic Saharan village and the gateway to Ennedi. On arrival in Fada we’ll meet our expedition team and complete some district formalities before heading out into the vast landscape of the Ennedi Massif. Our route to Warda camp passes a beautiful region of tassilian rock formations, tongues of sand and, in Terkey, we will visit one of the most important rock art sites in the region. After a day of adventure we arrive at Warda camp, our base for the next 3 nights. Dinner and overnight at Warda Camp. A day-to-day breakdown… 4th February 2021– NOHI-LABYRINTH-ARCHEI | ENNEDI Today we head out to explore the beautiful and verdant landscape of Wadi Nohi, amazing cave sites rich in paintings, the water formed Oyo labyrinth and finally the incredible wadi Archei.
    [Show full text]
  • Palynological Evidence for Gradual Vegetation and Climate Changes During the African Humid Period Termination at 13◦ N from a Mega-Lake Chad Sedimentary Sequence
    Clim. Past, 9, 223–241, 2013 www.clim-past.net/9/223/2013/ Climate doi:10.5194/cp-9-223-2013 of the Past © Author(s) 2013. CC Attribution 3.0 License. Palynological evidence for gradual vegetation and climate changes during the African Humid Period termination at 13◦ N from a Mega-Lake Chad sedimentary sequence P. G. C. Amaral1, A. Vincens1, J. Guiot1, G. Buchet1, P. Deschamps1, J.-C. Doumnang2, and F. Sylvestre1 1CEREGE, Aix-Marseille Universite,´ CNRS, IRD, College` de France, Europoleˆ Mediterran´ een´ de l’Arbois, BP 80, 13545 Aix-en-Provence cedex 4, France 2Departement´ des Sciences de la Terre, Universite´ de N’Djamena (UNDT) BP 1027 N’Djamena, Chad Correspondence to: P. G. C. Amaral ([email protected]) Received: 16 May 2012 – Published in Clim. Past Discuss.: 18 June 2012 Revised: 18 December 2012 – Accepted: 19 December 2012 – Published: 29 January 2013 Abstract. Located at the transition between the Saharan and period. However, we cannot rule out that an increase of Sahelian zones, at the center of one of the largest endorheic the Chari–Logone inputs into the Mega-Lake Chad might basins, Lake Chad is ideally located to record regional envi- have also contributed to control the abundance of these taxa. ronmental changes that occurred in the past. However, until Changes in the structure and floristic composition of the veg- now, no Holocene archive was directly cored in this lake. etation towards more open and drier formations occurred In this paper, we present pollen data from the first sed- after ca. 6050 cal yr BP, following a decrease in mean Pann imentary sequence collected in Lake Chad (13◦ N; 14◦ E; estimates to approximately 600 (−230/+600) mm.
    [Show full text]
  • Working Paper Or Information Paper
    APIRG/19 WP/14 Appendix 3.2J INTERNATIONAL CIVIL AVIATION ORGANIZATION VOLCANIC ASH CONTINGENCY PLAN AFI REGION First Edition - October 2012 THIS DOCUMENT IS ISSUED BY THE DAKAR AND NAIROBI ICAO REGIONAL OFFICES UNDER THE AUTHORITY OF THE APIRG 1 Page 2 of 32 Volcanic Ash Contingency Plan – AFI Region FOREWARD Within and adjacent to the Africa and Indian Ocean (AFI) Region there are areas of volcanic activities which are likely to affect flight in the AFI Region. The major volcanoes in the region are located in the following States: Algeria, Cameroon, Cape Verde Islands, Chad, Comoros Island, Democratic Republic of Congo, Djibouti, Eritrea, Ethiopia, France (Reunion Island), Kenya, Madagascar, Mali, Niger, Nigeria, Rwanda, Sao Tome and Principe, Spain (Canary Islands, Madeira), Sudan, Tanzania and Uganda. The names of the concerned volcano are listed in APPENDIX K (source: Smithsonian Institution). This document is the AFI Air Traffic Management (ATM) Volcanic Ash Contingency Plan which sets out standardised guidelines and procedures for the provision of information to airlines and en-route aircraft before and during a volcanic eruption. Volcanic contamination, of which volcanic ash is the most serious, is a hazard for safe flight operations. Mitigating the hazards posed by volcanic ash in the atmosphere and/or at the aerodrome cannot be resolved in isolation but through collaborative decision-making (CDM) involving all stakeholders concerned. During an eruption volcanic contamination can reach and exceed the cruising altitudes of turbine-powered
    [Show full text]
  • The Variability of Lake Chad : Hydrological Modelling and Ecosystem Services
    The variability of Lake Chad : hydrological modelling and ecosystem services 1 1 2 Jacques Lemoalle Jean-Claude Bader Marc Leblanc (1) IRD/MSE, UMR G-Eau, BP 64501, 34394 Montpellier Cx5, France Corresponding address : [email protected] (2) School of Earth and Environmental Sci., James Cook University, Cairns, Australia Abstract As in most of West and Central Africa, the rainfall regime over the Lake Chad basin has changed around 1970 from a humid to a dry period. This rainfall change is the cause of the changes in Lake Chad area. Lake Chad being a closed lake, its surface area has changed according to the lower water inputs from the watershed. The lake, which covered about 22000 km2 in the 1960s, is now divided into different individual seasonal or perennial lake basins. In the northern basin of the lake, the seasonally inundated area has varied from zero in dry years (as in 1985, 1987) to about 6000 km2 (1979, 1989 and 1999-2001). In the southern basin of the lake, the between year variability has markedly decreased. The changes in lake area and in the links between the lake basins have been modelled as a function of the river inputs. Satellite estimates of water area in the northern basin and gauge levels in the southern basin have been used as calibration data. The water volumes incorporated in and lost by the sediments during the annual wet and dry cycle have been taken into account in the model. The hydrologic changes are the driving forces for the natural resources associated with the lake i.e.
    [Show full text]
  • Lake Chad: Recent Dry Season Area Changes, Near Term Dry Season Area Projections, and Dry Season Area Projections Through the Year 2100
    LAKE CHAD: RECENT DRY SEASON AREA CHANGES, NEAR TERM DRY SEASON AREA PROJECTIONS, AND DRY SEASON AREA PROJECTIONS THROUGH THE YEAR 2100 by Frederick S. Policelli A dissertation submitted to Johns Hopkins University in conformity with the requirements for the degree of Doctor of Philosophy Baltimore, Maryland December, 2018 © 2018 Frederick S. Policelli All Rights Reserved Lake Chad, in the Sahel region of Africa is shallow, freshwater, and the terminal lake of an enormous (2.5 million km2) endorheic basin. The lake has exhibited a wide range of area over the centuries. More recently, some of the earliest satellite photographs of Lake Chad were taken in the 1960s when the lake area was estimated to be about 25,000 km2. During the late 1960s, the 1970s and the 1980s, a recurrent set of droughts caused the lake area to decrease sharply. During the period when the lake was drying, large areas of aquatic vegetation formed in the lake, while a small area of open water persisted. It appears likely that some researchers and the popular press have focused only on the small open water area when reporting the size of Lake Chad, because it is very challenging to detect and measure the area of flooded vegetation. Reports of a decrease of ninety to ninety-five percent of lake area, relative to lake area in the 1960s, led the Lake Chad Basin Commission (LCBC) to study an interbasin water transfer from the Ubangi River, a tributary to the Congo River. The motivation for this dissertation was to use satellite data and modeling results to provide information on the recent trends of total Lake Chad area (open water and flooded vegetation), and to provide statistical models and results for near term and long term modeling of the lake area.
    [Show full text]
  • Pleistocene Volcanism in the Anahim Volcanic Belt, West-Central British Columbia
    University of Calgary PRISM: University of Calgary's Digital Repository Graduate Studies The Vault: Electronic Theses and Dissertations 2014-10-24 A Second North American Hot-spot: Pleistocene Volcanism in the Anahim Volcanic Belt, west-central British Columbia Kuehn, Christian Kuehn, C. (2014). A Second North American Hot-spot: Pleistocene Volcanism in the Anahim Volcanic Belt, west-central British Columbia (Unpublished doctoral thesis). University of Calgary, Calgary, AB. doi:10.11575/PRISM/25002 http://hdl.handle.net/11023/1936 doctoral thesis University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. Downloaded from PRISM: https://prism.ucalgary.ca UNIVERSITY OF CALGARY A Second North American Hot-spot: Pleistocene Volcanism in the Anahim Volcanic Belt, west-central British Columbia by Christian Kuehn A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY GRADUATE PROGRAM IN GEOLOGY AND GEOPHYSICS CALGARY, ALBERTA OCTOBER, 2014 © Christian Kuehn 2014 Abstract Alkaline and peralkaline magmatism occurred along the Anahim Volcanic Belt (AVB), a 330 km long linear feature in west-central British Columbia. The belt includes three felsic shield volcanoes, the Rainbow, Ilgachuz and Itcha ranges as its most notable features, as well as regionally extensive cone fields, lava flows, dyke swarms and a pluton. Volcanic activity took place periodically from the Late Miocene to the Holocene.
    [Show full text]