DOCSLIB.ORG

Mineral Potential of Malawi

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Mineral Potential of Malawi Ministry of Energy and Mines REPUBLIC OF MALAWI Mineral potential of Malawi 1 Mineral deposits associated with alkaline Produced for the Ministry of Energy and Mines of magmatism (rare earth metals, coltan metals, Malawi by the British Geological Survey under the auspices of the UK Department for International nuclear metals, phosphate, etc.) Development. Ilomba )'Nb, Ne, U, Sod " Chitipa " Karonga Kimberlite X Ne, Sod LAKE )' )'Ne )'Amz " MZUZU Ne " )' Likoma island MZIMBA MA LAWI Nb, Ta, U, Zr Kanyika )' " NKHOTA KOTA Kanyika Courtesy of Globe Metals & Mining Ltd. Alkaline magmatism "Senga Salima " " Mchinji Alkaline magmatism in Malawi has occurred during " " Chipoka the early phases of intracontinental rifting events LILONGWE " Linthipe with melt generation by mantle upwellings beneath " thinned crust. Alkaline rocks are those in which the Dedza Mangoche " alkali content (Na2O +K2O) is more than can be taken Carbonatite/vents up by the feldspars with the available silica resulting Lake Malombe Balaka in the appearance of feldspathoids and/or Nepheline syenite plutons " Ne, Sod Early Ba, Flu, Mon, Sr )' Ne Cretaceous alkali pyroxenes/amphiboles. Alkaline rock types Syeno-granitic plutons )' )' Nepheline syenite Ca, Flu, Nb range from felsic to ultramafic and are found in Flu " ' Lake )' )Chilwa Perthitic complexes ZOMBA Ba, Ca, Nb, P several associations characterised by distinctive rock Mwanza " ' Nepheline and/or Flu )') aegirine gneisses Nb, Zr Flu, Ne types including carbonatites. Alkaline magmatic late Cambrian ' ) " LIMBE )' Neoproterozoic to " Charnockitic Suite BLANTYRE systems are important repositories of barite, fluorite, nepheline syenite, rare-earth metals, phosphate, Mineral deposits/occurrences Mulanje niobium, tantalum, thorium, uranium and zirconium. Amz Amazonite Zr Zircon Mts Ba Barytes Sod Sodalite They may also be sources of copper, titanium, Ca Limestone Sr Strontianite strontium, vermiculite and lateritic nickel. Flu Fluorite Ta Tantalum Mon Monazite U Uranium " Nsanje Nb Niobium Ne Nepheline Syenite January 2009 1096_Malawi_brochure_1c_final.indd 4 16/01/2009 14:18:41 Alkaline magmatic provinces and oceans have opened and closed. This The overlapping intrusions of Chikala, suites Neoproterozoic Rift belt has remained a zone Chaone, Mongolowe and Chinduzi were Malawi comprises alkaline rocks of the Pan of crustal weakness and a locus for alkaline emplaced along an east-west line. The African cycle (pre- and post- Mozambiquan magmatic activity during the Mesozoic. probable sequence of emplacement is syenite orogeny) and also of Early Cretaceous age - nepheline-bearing alkali feldspar syenite that relate to the rifting of the Gondwana The Early Cretaceous Chilwa Alkaline – nepheline syenite. The plutons become supercontinent. The East African Rift is a present Province of southern Malawi has an more silica-undersaturated towards the west day expression of a major crustal suture. exceptional range of lithologies from with an increase in the relative abundance of carbonatite to granite. It lies at the southern nepheline-rich rocks and the appearance of The Neoproterozoic North Nyasa end of the East African rift and is unique for sodalite. Alkaline Province (NNAP) of central and its essentially intrusive character. The largest northern Malawi consist of seven intrusions plutons consist of syenite and peralkaline Zomba-Malosa consists of a central plug of (Kasungu, Chipala, Chikangawa, Mphompha, granite with smaller intrusions comprising syenite, an inner ring of quartz microsyenite Telelele Hill, Ilomba and Ulindi) that lie along syenite, nepheline syenite, sodalite syenite and outer ring of peralkaline granite. Malosa a north-south trend roughly parallel to the and carbonatite. Metamorphosed basanite/ consists of a heterogeneous mixture of quartz current rift valley. The dominant lithology nephelinite volcanics are mainly preserved in syenite and granite. The western side of is nepheline syenite, but alkali syenite and down-faulted blocks. Extrusion of nephelinitic the pluton is cut by a rift valley fault with granite occur at Mphompha and pyroxenites lavas and emplacement of nepheline and downthrow to the west of >1000m. outcrop adjacent to, and within the Ilomba sodalite syenites at c.135Ma was followed by intrusion. Available data indicate that the nepheline syenites and syenites at c.126Ma Cretaceous intrusive activity in the northern NNAP plutons were emplaced at 750–710Ma and large syenite-peralkaline granite plutons part of the country includes kimberlitic and subsequently metamorphosed at at c.113Ma. breccias, dolerite dykes, diorite and c.450Ma during the Pan African event. pyroxenite intrusions. Chilwa Island is a multiple carbonatite The Ilomba and Ulindi intrusions on the complex composed of sideritic carbonatite, Rare Earth Metals northern border with Tanzania occur within ankeritic sövite and sövite. An arcuate body Rare Earth Metals include the lathanides, the northwest-trending Songwe Syenite of feldspathic breccia surrounds much of the scandium and yttrium. They are mainly which intruded gneisses of Ubendian age. complex and separates the main carbonatite used as catalysts in oil refining, catalytic Ilomba comprises a central mass of aegirine- phases from the outer zone of fenitized converters, the glass industry, colouring nepheline microsyenite surrounded by an gneisses. The carbonatites have been intruded agents, fibre optics, camera lenses, TV tubes, incomplete ring of locally sodalite-rich biotite- by ring dykes of nepheline syenite and ijolite Sm-Co permanent magnets, high strength nepheline syenites and minor pyroxenites and dykes and plugs of alnöite, camptonite, alloys and synthetic minerals for laser within coarse aegirine-bearing perthosites. trachyte, nephelinite and phonolite. applications. The main economic minerals are bastnaesite and monazite. The late Pan African alkaline ring Junguni is essentially composed of coarse- complexes of southern Malawi include grained sodalite-nepheline±cancrinite Monazite occurrences are widespread Thambani, Bilila and the east-west line of syenite. It is the most strongly silica- throughout the Chilwa Alkaline Province and Chingale, Mlindi, Little Michuru and Ntonya. undersaturated peralkaline pluton in the locally form residual concentrations in heavy They typically contain metapyroxenite cores province. mineral sands (see brochure 4). with peripheries of syenite and hybrid rocks. In addition there is a swarm of biotitite bodies (the Majete group) that are considered to be metasomatised derivatives of intrusive ultramafic rocks. The Mlindi ring complex, dated at 495Ma, contains from the centre outward: pyroxenite, gabbronorite to syenogabbro, gabbro-diorite and syenite. The entire ring complex is cut by dykes and veins of pegmatite, microsyenite and lamprophyre. Nepheline is unknown and there is no association with carbonatite. Deformed alkaline rocks and carbonatites may mark Proterozoic suture zones where View of Kangankunde Hill. 2 1096_Malawi_brochure_1c_final.indd 5 16/01/2009 14:18:42 EAST AFRICAN CARBONATITES — intrusive carbonate-mineral-rich igneous rocks Calcite-carbonatite or sövite (calciocarbonatite) e.g Chilwa Island Rock types Dolomite-carbonatite or beforsite (magnesiocarbonatite) Ferroan-or ankeritic-carbonatite (ferrocarbonatite) e.g Kangankunde Natrocarbonatite — Na, K and Ca carbonates - not known in Malawi Tectonic environment Spatially related to faults within rifted or incipiently rifted continental plates; associated with alkaline volcanic activity Morphology Ring complexes, plugs, cone sheets, dykes and vent agglomerates Associated rock types Nepheline syenite, pyroxenite, ijolite, melteigite, phonolite and more rarely mica peridotite; halo of fenitization (alkali metasomatism) Deposit types Banded metasomatic replacements, disseminations, breccia zones, dykes, sills and irregular masses — commonly multi-stage Apatite-magnetite type: apatite±pyrochlore±columbite±perovskite Ore types RE-type: monazite±bastnaesite±baryte±strontianite±rhodochrosite General: calcite/dolomite±fluorite±sulphides±Ti minerals±zircon Trace element geochemistry Enriched in F,Th, U, Ti, Zn, Nb, Y, Mo, Cu, V, P, Mn, S, La, Ce, Sm, Eu, Pb, Zr & Ba MONAZITE (REE) MANGOCHI grade of 4.24% REO using a 3.5% REO cut-off 1 Tundulu OCCURRENCES 25 (adapted from MMNRE 19 2 Nkalonje grade and remains open at depth. Testwork 20 3 Matoponi publ. 2006) 21 LAKE LAKE 22 23 shows that the deposit is amenable to low- MALOMBE CHIUTA 4 Songwe 24 5 Mikomwa cost gravity separation producing a 60% REO 6 Chipalanje Junguni concentrate. 7 Salambidwa BALAKA 11 15˚ 8 Namangale 15 Railway 9 Namingo The Tundulu Complex contains large LISUN 12 G 14 10 Chilwa Island W quantities of REE minerals, mainly E 11 Kadongosi 13 R 12 Mongolwe I Mt bastnaesite, in addition to substantial E V 16 E Malosa 13 Chikala 10 LAKE U R reserves of apatite. The rocks of Nathache CHILWA Q 14 Kangankunde 17 Zomba I Mt ZOMBA B 15 Chaumbwi Hill are estimated to contain >3,225,000 MOZAMBIQUE 18 1 M 16 Kapiri A 17 Nsengwa tonnes at 2.4% REO per 30 metre depth. 2 3 Z O 18 Mlindi MWANZA 4 9 M 19 Nsala S H 5 20 Kongwe Strontianite (a source of strontium) Carbonatite I R 7 8 E 6 PHALOMBE 21 Liperembe Agglomerate BLANTYRE would be recovered as a by-product R 22 Kawanula I Granite, Gneiss V E 23 Aligomba of any monazite exploitation at R Mulanje Syenite/Pyroxenite 16˚ Mts 24 Achirundu Kangankunde. Indicated reserves are Nepheline-syenite 25 Chiloli 11Mt at 8% Sr. Strontium is used in Syenite/ 0 50
Load more

Recommended publications
  • Feldspar and Nepheline Syenite 2016
    2016 Minerals Yearbook FELDSPAR AND NEPHELINE SYENITE [ADVANCE RELEASE] U.S. Department of the Interior January 2020 U.S. Geological Survey Feldspar and Nepheline Syenite By Arnold O. Tanner Domestic survey data and tables were prepared by Raymond I. Eldridge III, statistical assistant. In 2016, feldspar production in the United States was representing 46% of the 2016 production tonnages listed in estimated to be 470,000 metric tons (t) valued at $33.1 million, tables 1 and 2. an almost 10% decrease in quantity and a 11% decrease in Feldspar was mined in six States (table 3). North Carolina value compared with 2015 (table 1). Exports of feldspar in 2016 was by far the leading producer State; the remaining five were, decreased by 61% to 5,890 t, valued at $1.5 million, and imports in descending order of estimated output, Virginia, California, of feldspar decreased by 69% to 36,900 t, valued at $3.4 million. Idaho, Oklahoma, and South Dakota. Production was from Imports of nepheline syenite (predominantly from Canada) 10 mines and beneficiating facilities—4 in North Carolina, 2 in increased by 27% to about 572,000 t valued at $73 million. California, and 1 in each of the 4 remaining States (table 3). World production of feldspar in 2016 was 23.4 million metric I-Minerals Inc. continued the mine permitting process for tons (Mt) (tables 1, 7). its Helmer-Bovill project in north-central Idaho; the mine Feldspars, which constitute about 60% of the earth’s crust, would produce potassium feldspar, halloysite, kaolin, and are anhydrous aluminosilicate minerals of two main groupings: quartz.
    [Show full text]
  • There Is More Than 3TG the Need for the Inclusion of All Minerals in EU Regulation for Conflict Due Diligence
    There is more than 3TG The need for the inclusion of all minerals in EU regulation for conflict due diligence SOMO Paper | January 2015 Companies that use minerals in their products risk International standards and regulation contributing to conflict financing or human rights abuses via their mineral supply chains, especially if upstream Normative standards suppliers are located in conflict zones. This problem is Under the European Convention on Human Rights and being addressed by the European Commission (EC), international human rights law, European member states which has proposed a new regulation with a voluntary have an obligation to ensure that business enterprises due diligence framework to address the risk of financing operating within their jurisdiction do not cause or armed groups and security forces, and mitigate other contribute to human rights violations. The United Nations adverse impacts associated with the extraction, transport Guiding Principles on Business and Human Rights (UNGP) and trade of four particular minerals: tin, tantalum, and the Organisation for Economic Development and tungsten and gold (3TG). Cooperation’s Guidelines for Multinational Enterprises (OECD Guidelines) set clear standards for business enter- This briefing paper discusses one specific issue in the prises to respect human rights, conduct human rights due proposed EC regulation – the limited number of conflict diligence and implement measures to prevent, address and minerals it includes. It puts the case that the decision to redress any human rights violations.1 The UNGP prescribe focus on the import of minerals and metals containing or that states need to “ensure that their current policies, consisting of 3TG is arbitrary and far too limited to achieve legislation, regulations and enforcement measures are the proposal’s objective of reducing the financing of armed effective in addressing the risks of business involvement groups and security forces through mineral proceeds in in gross human rights abuses”.2 The UNGP have special conflict-affected and high-risk areas.
    [Show full text]
  • Green Extraction of Niobium and Tantalum for Ethiopian Kenticha Ores by Hydrometallurgy Process: a Review
    Material Science & Engineering International Journal Mini Review Open Access Green extraction of niobium and tantalum for Ethiopian kenticha ores by hydrometallurgy process: a review Abstract Special Issue - 2018 This review presents an overview of the currently mined tantalite ores in Ethiopia Berhe Goitom Gebreyohannes,1 Velazquez (in particular Kenticha ores) and potentialities to extract niobium (Nb) and tantalum del Rosario Alberto,2 Bogale Tadesse,3 (Ta) products using green technologies. The foremost source of niobium and tantalum 4 5 is the columbite-tantalite mineral or “coltan”. Since hydrometallurgical methods are Abubeker Yimam, Girma Woldetinsae, 1 most commonly used to recover these metals from raw materials, Solvent Extraction Department of Chemistry, College of Natural and Computational Sciences, Mekelle University, Ethiopia (SX) processes have been used for producing pure niobium and tantalum products. 2Jimma Institute of Technology, Jimma University, Ethiopia All commercialized “SX” processes are exclusively conducted in the presence of 3Department of Mining Engineering and Metallurgical fluoride ions, most frequently in a mixture with a mineral acid such as sulphuric or Engineering, Western Australia School of Mines, Curtin hydrochloric acid. Due to increasingly stringent regulations concerning the protection University, Australia of human health and environment, there is an urgent need to develop novel aqueous 4Process Engineering and Industrial Technology, Addis Ababa and organic systems to reduce or eliminate the use of harmful fluorides. Because the University, Ethiopia Kenticha pegmatite spodumene has an excess percent of uranium, certain markets 5Research and Development Directorate, Ministry of Mines, stopped importations of Ethiopian coltan. So, investigations are required to indentify Petroleum and Natural Gas, Ethiopia aqueous complex systems and solvent extraction systems to enable the purification of niobium and tantalum without the use of fluorides.
    [Show full text]
  • Cdm Annual Report 2015 EN
    CHAMBRE DES MINES FEDERATION DES ENTREPRISES DU CONGO 2015 DRC MINING INDUSTRY ANNUAL REPORT IN THIS ISSUE PRODUCTION ● PERU/ZAMBIA/DRC COMPARISON ● DRC BUSINESS CLIMATE ● CSR ● AND MORE www.chambredesminesrdc.com CONTENT 2 Content 3 Editorial 4 2015 Production Data 9 3T (Tin , Tantalum and Tungsten) 10 2015 3T Supply Chain EITI Report: The mining industry is still highly active within the DRC 11 Business Climate 12 Jobs 13 Lack of energy 14 Artisanal Mining 15 Commodity-Price Trend 16 Highlights - South Kivu Peru/ Zambia/ DRC comparison 17 2015 CSR Report 2 Chambre des Mines - 2015 DRC Annual Report EDITORIAL The year 2015 was marked by a fall in prices for metals and commodities, the worst since the global economic crisis of 2008/2009. Although the DRC has adjusted rather well to this new scenario - gold production was up 30% and copper showed only a 3% decrease - the economic activity of the country will nevertheless be impacted significantly in 2016. Copper production in Q4 2015 was already more than 12% lower than in Q4 2014. Some analysts believe that the crisis could last longer than the previous one because it is powered by a slowdown in Chinese demand and increased mining production worldwide. This will have major consequences on employment and on tax reve- nues in the DRC, where the country's growth depends heavily on the mining sector. However, there are reasons for optimism. The country still full of many world class mining, industrial and agricultural pro- jects; new mines started commercial production in 2015, and other major projects are expected to emerge in the coming years.
    [Show full text]
  • Deposits, Resources, Exploration Methods and Market (Simandl Et Al
    Tantalum and Niobium: Deposits, Resources, Exploration Methods and Market - A Primer for Geoscientists G. J. Simandl, R. O. Burr, D. L. Trueman and S. Paradis An article reprinted from Geoscience Canada THEJOURNALYOUWANT TOREAD..... Photobythelate Harold(Hank)Williams TheAppalachiansweren’tbuiltinaday. Thesameappliestoaworld-classjournal. Geoscience Canada is a quarterly journal published by the Geological Association of Canada (GAC). We are a not-for-profit publication funded by subscriptions, grants and the generous support of researchers and readers. The content of the journal is diverse, ranging from technical papers to review articles, commentaries, columns and book reviews. We offer a smooth and personalized approach to the review and processing of papers, and accepted contributions will generally appear as ‘in press’ within a few months of their initial submission, and in final form within six to nine months. We have a particular interest in overview articles that have long-term educational value. Annual subscriptions to Geoscience Canada cost much less than a daily cup of coffee from your favourite chain. GAC members can subscribe for a mere $50 and non-members for only $75 (only $15 for students). Even if your institution already carries a subscription on your behalf, a convenient personal subscription helps to support non-profit Earth Science publishing in Canada, which benefits all. Visit our website and also GAC for more information. www.geosciencecanada.ca www.gac.ca GEOSCIENCE CANADA Volume 45 2018 85 SERIES Abu Dabbab, Egypt), peralkaline complexes (e.g. Nechalacho, Canada), weathered crusts overlying the previously mentioned deposit types, and in placers. Niobium (Nb) resources with the highest economic potential are in weathered crusts that overlie carbonatite complexes (e.g.
    [Show full text]
  • Investing in the Minerals Industry in Liberia
    ANDS, MIN L ES F O & Y GICAL SU E R LO RV N O E T E Y E S G I R G N I Y M R E IA P R UB E LIC OF LIB Investing in the minerals industry in Liberia liberia No4 cover.indd 1 21/01/2016 09:51:14 Investing in the minerals industry in Liberia: ▪▪ Extensive Archean and Proterozoic terranes highly prospective for many metals and industrial minerals, but detailed geology poorly known. ▪▪ Gold, iron ore and diamonds widespread, with new mines opened since 2013 and other projects in the pipeline. ▪▪ Known potentially economic targets for diamonds, base metals, manganese, bauxite, kyanite, phosphate, etc. ▪▪ Little modern exploration carried out for most mineral commodities with the exception of gold and iron ore. ▪▪ National datasets for geology, airborne geophysics and mineral occurrences available in digital form. ▪▪ Modern mineral licensing system. Introduction The Republic of Liberia is located in West Africa, in Liberia. Furthermore, Liberia is richly endowed bordered by Sierra Leone, Guinea, Côte d’Ivoire with natural resources, including minerals, water and to the south-west by the Atlantic Ocean and forests, and has a climate favourable to (Figure 1). With a land area of about 111 000 km2 agriculture. Since the cessation of hostilities the and a population of nearly 4.1 million much of country has made strenuous efforts to strengthen Liberia is sparsely populated comprising rolling its mineral and agricultural industries, mostly plateaux and low mountains away from a narrow timber and rubber. flat coastal plain. The climate is typically tropical, hot and humid at all times, with most rain falling Mineral resources, especially iron ore, have in the in the summer months.
    [Show full text]
  • Deforestation Trends in the Congo Basin Reconciling Economic Growth and Forest Protection Public Disclosure Authorized
    Deforestation Trends in the Congo Basin Reconciling Economic Growth and Forest Protection Public Disclosure Authorized WORKING PAPer 4 | Mining Kirsten Hund Carole Megevand with Edilene Pereira Gomes Public Disclosure Authorized Marta Miranda Erik W. Reed Public Disclosure Authorized Public Disclosure Authorized APRIL 2013 Deforestation Trends in the Congo Basin Reconciling Economic Growth and Forest Protection WORKING PAPer 4 | Mining Kirsten Hund Carole Megevand with Edilene Pereira Gomes Marta Miranda Erik Reed APRIL 2013 Working Paper 4: Mining iii CONTENTS ACRONYMS ....................................................................................................................................................vii AcknoWLedgments .................................................................................................................................ix IntrodUctIon .............................................................................................................................................xi Chapter 1. MIneraL WeaLth IN the Congo BasIN: LargeLY Untapped.........................1 Geology and Associated Mineral Resources ................................................................................................1 Mining Sector in the Congo Basin ....................................................................................................................3 Types of Mining Operations ........................................................................................................................4
    [Show full text]
  • NI 43-101 Songwe REE Deposit
    NI 43-101 Technical Report and Mineral Resource Estimate for the Songwe Hill Rare Earth Element (REE) Project, Phalombe District, Republic of Malawi Prepared by The MSA Group (Pty) Ltd for: Mkango Resources Ltd Authors: Scott Swinden Consulting Geologist Ph.D., P.Geo. Michael Hall Consulting Geologist Resources Pr.Sci.Nat., MAusIMM Effective Date: September 30, 2012 Date of Signature: November 22, 2012 Table of Contents 1 Summary......................................................................................................................................... viii 1.1 Introduction.............................................................................................................................viii 1.2 Property, Location and Ownership.........................................................................................viii 1.3 Geology and Mineralization....................................................................................................viii 1.4 Status of Exploration ................................................................................................................ix 1.5 Mineral Resources.................................................................................................................... x 1.6 Conclusions and Recommendations........................................................................................xi 2 Introduction..................................................................................................................................... 12 2.1 Scope of Work
    [Show full text]
  • Paper Number: 736 COLTAN in Colombia: Strategic Or Conflict Material? Bonilla, A.1,2, Franco, J.A.1 , Amaya, Z.1 and Cramer, T.1,2
    Paper Number: 736 COLTAN in Colombia: strategic or conflict material? Bonilla, A.1,2, Franco, J.A.1 , Amaya, Z.1 and Cramer, T.1,2 1Universidad Nacional de Colombia, Ciudad Universitaria, Bogotá, [email protected] 2Grupo de Estudios en Geología Económica y Mineralogía Aplicada (GEGEMA), Universidad Nacional de Colombia, Departamento de Geociencias. __________________________________________________________________________ The Colombian part of the Amazonian Craton constitutes less than 10% of this Precambrian nucleus of South America, with outcrops in the eastern Vichada, Guainía, Vaupes, Caquetá and Guaviare departments, but most of the craton is covered by Tertiary and Quaternary sediments as well as by tropical forest. As with nearly all eastern Colombia it is inhabited mainly by indigenous tribes but serves also as an important region for illegal armed groups that use this inaccessible area to hide from the Colombian State and carry out illicit activities including mining in protected natural parks, in some cases controlled by the FARC, or to launder money from the drug trafficking. Important mining sites use alluvial and supergene deposits where valuable minerals are concentrated near the primary source rocks. Our research revealed that strategic minerals formed since the Mesoproterozoic by several metamorphic, magmatic and sedimentary events, outcrop in metasedimentary and granitic mountains and inselbergs. For example, wolframite from the Zancudo site in the central Guainía department is a greisen-type hübnerite associated with gold and bismuth hosted in metasedimentary rocks of the Maimachi Formation. Nb-Ta-rutile and columbite from south Guainía department are in pegmatites related to Mesoproterozoic A-type granites. Some columbite-tantalite occurrences in alluvial deposits are associated with beryl.
    [Show full text]
  • Alkaline Magmas in Zones of Continental Convergence
    1 Alkaline magmas in zones of continental convergence: 2 The Tezhsar volcano-intrusive ring complex, Armenia 3 4 Krzysztof Sokół1,2, Ralf Halama1*, Khachatur Meliksetian3, Ivan 5 P. Savov4, Gevorg Navasardyan3, Masafumi Sudo5 6 7 1 School of Geography, Geology and the Environment, Keele University, Keele, ST5 5BG, 8 United Kingdom 9 2 (Present address) School of Earth and Environmental Sciences, University of St Andrews, 10 St Andrews, KY16 9AL, United Kingdom 11 3 Institute of Geological Sciences, Armenian National Academy of Sciences, 24a Marshal 12 Baghramian Avenue, 0019, Yerevan, Republic of Armenia 13 4 School of Earth and Environment, University of Leeds, Leeds, LS2 9JT, United Kingdom 14 5 Institute of Earth and Environmental Science, University of Potsdam, Karl-Liebknecht- 15 Str. 24-25, 14476 Potsdam, Germany 16 17 * Corresponding author contact information: 18 Ralf Halama 19 School of Geography, Geology and the Environment 20 Keele University 21 Keele, ST5 5BG, United Kingdom 22 E-mail: [email protected] 23 Phone: +44 (0) 1782 7 34960 1 24 Abstract 25 Alkaline igneous rocks are relatively rare in settings of tectonic convergence and little 26 is known about their petrogenesis in these settings. This study aims to contribute to a 27 better understanding of the formation of alkaline igneous rocks by an investigation of the 28 Tezhsar volcano-intrusive alkaline ring complex (TAC) in the Armenian Lesser Caucasus, 29 which is located between the converging Eurasian and Arabian plates. We present new 30 petrological, geochemical and Sr-Nd isotope data for the TAC to constrain magma genesis 31 and magma source characteristics.
    [Show full text]
  • Tools and Workflows for Grassroots Li–Cs–Ta (LCT) Pegmatite Exploration
    minerals Review Tools and Workflows for Grassroots Li–Cs–Ta (LCT) Pegmatite Exploration Benedikt M. Steiner Camborne School of Mines, University of Exeter, Penryn TR10 9FE, UK; [email protected] Received: 22 July 2019; Accepted: 17 August 2019; Published: 20 August 2019 Abstract: The increasing demand for green technology and battery metals necessitates a review of geological exploration techniques for Li–Cs–Ta (LCT) pegmatites, which is applicable to the work of mining companies. This paper reviews the main controls of LCT pegmatite genesis relevant to mineral exploration programs and presents a workflow of grassroots exploration techniques, supported by examples from central Europe and Africa. Geological exploration commonly begins with information gathering, desktop studies and Geographic Information System (GIS) data reviews. Following the identification of prospective regional areas, initial targets are verified in the field by geological mapping and geochemical sampling. Detailed mineralogical analysis and geochemical sampling of rock, soil and stream sediments represent the most important tools for providing vectors to LCT pegmatites, since the interpretation of mineralogical phases, deportment and liberation characteristics along with geochemical K/Rb, Nb/Ta and Zr/Hf metallogenic markers can detect highly evolved rocks enriched in incompatible elements of economic interest. The importance of JORC (Joint Ore Reserves Committee) 2012 guidelines with regards to obtaining geological, mineralogical and drilling data is discussed and contextualised, with the requirement of treating LCT pegmatites as industrial mineral deposits. Keywords: LCT; pegmatite; lithium; exploration; targeting 1. Introduction Over the last four decades research into rare metal Li–Cs–Ta (LCT) pegmatite mineralisation has predominantly focused on the understanding of late-stage magmatic fractionation and hydrothermal alteration processes enriching incompatible elements of potential economic interest in felsic peraluminous melts.
    [Show full text]
  • Production, Reserves, and Processing of Feldspar and Feldspathoid Rocks in the Czech Republic from 2005 to 2019—An Overview
    minerals Article Production, Reserves, and Processing of Feldspar and Feldspathoid Rocks in the Czech Republic from 2005 to 2019—An Overview Jan Zahradník 1,2 , Jakub Jirásek 3,*, Jaromír Starý 4 and Martin Sivek 2 1 LB MINERALS, s.r.o., Tovární 431, 330 12 Horní Bˇríza, Czech Republic; [email protected] 2 Department of Geological Engineering, Faculty of Mining and Geology, Vysoká Škola Báˇnská-Technical University of Ostrava, 17. listopadu 15/2172, 708 00 Ostrava-Poruba, Czech Republic; [email protected] 3 Department of Geology, Faculty of Science, Palacký University Olomouc, 17. listopadu 1192/12, 771 46 Olomouc, Czech Republic 4 Czech Geological Survey, Klárov 3, 118 21 Praha, Czech Republic; [email protected] * Correspondence: [email protected] Received: 5 July 2020; Accepted: 10 August 2020; Published: 17 August 2020 Abstract: This paper aims to characterize and interpret the trends in reserves, resources, and mine production of feldspar and feldspathoid rocks during 2005–2019 in the Czech Republic. With over 101 Mt of total resources and 22 Mt of reserves, feldspar belongs to the crucial industrial minerals of the Czech Republic. With annual outputs of approximately 400–450 kt of feldspars and 20–35 kt of feldspathoid rocks (nepheline syenite), the Czech Republic ranks among the top European and world feldspar producers. Most of the production comes from leucocratic granitoid rocks (key active deposit: Krásno-Vysoký Kámen), followed by sedimentary rocks (key active deposit: Halámky), and granitic pegmatites (key active deposit: Luženiˇcky).Nepheline syenite is mined at a single deposit. All deposits are extracted from open pits (quarries).
    [Show full text]