Image de couverture de: - Sediment-hosted Pb-Zn /Cu-Ba) Mineralisation within the Coastal Branches of the Damara Orogen, Namibia - A Review (by G. Borg and C. Gauert) Metamorphism and Geochemistry of the Paleoproterozoic Birimian Sefwi Volcanic Belt, Ghana, West Africa (by K. Galipp, W. Hirdes, R. Klemd)

Sediment-hosted Pb-Zn /Cu-Ba) Mineralisation within the Coastal Branches of the Damara Orogen, Namibia - A Review (by G. Borg and C. Gauert)

Metamorphism and Geochemistry of the Paleoproterozoic Birimian Sefwi Volcanic Belt, Ghana, West Africa (by K. Galipp, W. Hirdes, R. Klemd)

Ed.: Gregor Borg; Christoph D. Gauert; Karsten Galipp; ; Wolfgang Hirdes; Reiner Klemd

2003. 191 pages, 29 figures, 13 tables, 17x24cm, 430 g
Langue: English

(Geologisches Jahrbuch Reihe D, Band D 111)

ISBN 978-3-510-95907-5, paperback, Prix: 34.00 €

en stock, disponible

Bon de commande

fichier Bib TeX

Mots-clefs

metamorphism • geochemistry • mineral • sedimentary • Metamorphose • Geochemie • Mineral • Ablagerungen

Contenu

Inhaltsbeschreibung Haut de page ↑

Die Studie im ersten Teil des Heftes ist das Ergebnis einer in Namibia und Deutschland durchgeführten Literaturrecherche zu sedimentgebundenen Blei-Zink-(Kupfer-Barium)-Vorkommen in den Pan-Afrikanischen Kaoko- und Gariep-Faltengürteln der nördlichen und südlichen Küstenregion in Namibia. Die Studie zeigt, dass metallogenetische Untersuchungen der Buntmetallmineralisationen in diesen orogenen Gürteln Namibias einen aktuellen Forschungsschwerpunkt darstelllen. Der zweite Teil beschäftigt sich mit Resultaten einer Studie, die sich mit P-T-Bedingungen der eburnischen Regionalmetamorphose befasst, die den paläoproterozoischen, ca. 2180 Ma alten Sefwi-Vulkanitgürtel in Ghana überprägt hat. Die Studie umfasst detaillierte mineralchemische und texturelle Untersuchungen an Einzelmineralien, kombiniert mit konventioneller Geothermobarometrie.

Content Description Haut de page ↑

The first part of the volume presents a literature study of published papers and information on sediment-hosted Pb-Zn (Cu-Ba) deposits of the Pan-African Kaoko Belt and Gariep Belt in the coastal region of southern and northern Namibia. The study revealed that applied metallogenetic research of sediment-hosted base metal deposits has recently become a major topic again. The second part of the volume reports results of a study on P-T conditions of regional metamorphism of the Eburnean tectono-thermal event in the c. 2180 Ma old Sefwi volcanic belt which forms part of the Paleoproterozoic Birmian Supergroup in Ghana/West Africa.

Contents Haut de page ↑

Gregor Borg & Christoph D. K. Gauert:


Sediment-hosted Pb-Zn (Cu-Ba) Mineralisation
within the Coastal Branches of the Damara Orogen,
Namibia ? A Review


Preface
1 Introduction
1.1 Aims of the study
2 Global and Regional Economic Background
2.1 The changing situation in African mineral exploration
2.2 Economic and geological significance of SHBMS deposits (non MVT)
3 A short Summary of the Pan-African Geology of Namibia
3.1 Regional Setting and Evolution of the Pan African Orogenic Belts in
Namibia
3.1.1 Sedimentary History and Plate Tectonic Evolution
4 Passive Continental Margins and their Potential for Mineral Deposits
4.1 Metal sources
4.2 Fluids
4.3 Basin dewatering
4.4 Thermal convection-driven fluid flow
4.5 Gravity-driven fluid flow
4.6 Tectonism as an engine for fluid flow
5 Relevant Genetic Models for SH(M)S Deposits
5.1 Sedex deposits (e.g. Meggen, Rammelsberg, Irish-type)
5.2 Epigenetic impregnation- or replacement-type deposits (Pennine-type,
Mechernich-type, Laisvall-type, Kupferschiefer-type, excluding MVT)
5.3 MVT-deposits and Tsumeb-type deposits
5.4 The timing of metallogenesis
6 Logistical Access to the Areas of Investigation
6.1 Exploration history of the deposits and legal access to data
6.1.1 Rosh Pinah Mine
6.1.2 The Skorpion deposit
6.1.3 The Tsongoari prospect
6.2 Legal access to data
7 Literature Evaluation
7.1 Pb-Zn in coastal Namibia
7.1.1 Publications
7.1.1.1 Comprehensive country-wide mineral studies
7.1.1.2 Structural, stratigraphic and metamorphic literature on coastal
Damara
7.1.1.3 Metallogenic literature
7.1.2 Relevant open file reports of the Geological Survey of Namibia (GSN)
7.1.2.1 Comprehensive country-wide mineral studies
7.1.2.2 Maps
7.1.2.3 Regional surveys
7.1.3 Company archives
7.1.3.1 Tsongoari
7.1.3.2 Skorpion
7.1.3.3 Rosh Pinah
7.2 Other available information and material
8 Regional Criteria for the identification of SHMS occurrences
8.1 Regional and local geophysics
8.2 Remote sensing techniques
8.3 Facies distribution mapping, regional geochemistry and heavy
mineral investigations
9 Scientific Problems and Possible Solutions (methods of investigations)
9.1 Regional criteria for the identification of potentially mineralised sites
9.2 F.I.-studies (chances and problems)
9.3 IR-microscopy
9.4 CL-microscopy
9.5 Ga-Ge thermometry
9.6 S- and Pb-isotope studies
9.7 Trace element geochemistry
9.8 Alteration assemblages (albite, Fe-chlorite, Mn-halos)
9.9 Geochemistry
9.10 Tourmaline as ore-related exhalative mineral
9.11 Ore mineral/metal zonation
9.12 Regional traverses for basin reconstruction and vent location
9.13 Interpretation of regional and local geophysical data
9.14 Application of GIS to metallogenetic studies
10 Scientific Challenges and Methods of Investigation - A Synthesis
11 References


Karsten Galipp, Wolfgang Hirdes & Reiner Klemd:


Metamorphism and Geochemistry of the Paleoproterozoic Birimian Sewfi Volcanic
Belt (Ghana, West Africa)


1 Introduction
2 General Geology of Birimian Rocks
2.1 Regional setting
2.2 Local setting of the project area
2.1 Regional setting
2.2 Local setting of the project area
3 Geochemistry
3.1 Mafic Volcanics
3.2 Granitoids and gabbros
4 Petrography and mineral chemistry
4.1 Mafic Volcanics
4.2 Granitoids
4.3 Metasediments of the Sefwi belt
4.4 General comments on metamorphic conditions of the Sefwi belt
5 Geothermobarometry
5.1 Geothermometry
5.2 Geobarometry
5.3 Interpretation of P-T estimates
6 Discussion and Conclusion
7 References