This study re-evaluates the characteristics of Cu-Pb-Ag and Fe-Mn ore mineralization of the Kombat Mine and Gross Otavi Mine based on field geology, fluid inclusions, petrology, mineralogy, and geochemistry. This is t...This study re-evaluates the characteristics of Cu-Pb-Ag and Fe-Mn ore mineralization of the Kombat Mine and Gross Otavi Mine based on field geology, fluid inclusions, petrology, mineralogy, and geochemistry. This is to determine the genetic relationship between Fe-Mn and Cu-Pb-Ag mineralization. The study has established that the Cu-Pb-Ag ore at the Kombat Mine can be classified as a variant of MVT-type deposit, whereas the Fe-Mn ore can be classified as a stratiform-syn-sedimentary deposit. The formation of the MVT-type deposit is associated with a hydrothermal fluid system with a mean temperature of 183<span style="white-space:nowrap;">°C and mean salinity of 12.85 wt. % NaCl equivalent. The syn-sedimentary Fe-Mn ore, which is largely associated with calc-silicate lithologies, consists mainly of magnetite and hematite with minor pyrite, hausmannite and jacobsite, and was deposited by diagenetic and mixed diagenetic-hydrogenetic processes under changing oxic and anoxic conditions within the sedimentary basin. Acceptable geochemical exploration indicators of the existing mineralization include anomalous values above 0.5% Cu, 0.2% S;0.05% Pb;0.04% As;0.01% Zn;V, W, Mo, and Ag are 0.002%. Mineralogical indicators include chalcopyrite, bornite, covellite and galena with minor chalcocite, sphalerite, and tennantite for the Cu-Pb MVT-type ores at Kombat Mine.展开更多
The scientific objectives and research program of the IGCP-646 project(2015-2018)cuts across many disciplines and includes various aspects of continental basement geology,resource exploration(mineral,water and hydroca...The scientific objectives and research program of the IGCP-646 project(2015-2018)cuts across many disciplines and includes various aspects of continental basement geology,resource exploration(mineral,water and hydrocarbons),geohazard mitigation,and climate change,all of which are of critical importance to developing countries,particularly in parts of West Africa where population pressures are on the rise.Considerable emphasis was placed on capacity building,creation of opportunities for young scientists to undertake higher degrees programs,knowledge transfer and training.The SIDA-funded“pilot project”IGCP-616Y(started in 2012),focused on three objects(i)crustal architecture,tectonic evolution and regional geology of Central Africa and the connection with NE Brazil;(ii)the Mesozoic continental rifting and breakup leading to a better integration of the onshore and offshore geology;(iii)clarification and quantification of the links between basement structures,neotectonics,climate change and landscape evolution.The IGCP-616Y and IGCP-646 projects consisted of over 250 researchers,from different countries.In the course of the projects,six annual meetings,four field trips/workshops,as well as several training sessions were organized.Here we provide a summary of the scientific targets of the projects and a summary of the organized activities.展开更多
文摘This study re-evaluates the characteristics of Cu-Pb-Ag and Fe-Mn ore mineralization of the Kombat Mine and Gross Otavi Mine based on field geology, fluid inclusions, petrology, mineralogy, and geochemistry. This is to determine the genetic relationship between Fe-Mn and Cu-Pb-Ag mineralization. The study has established that the Cu-Pb-Ag ore at the Kombat Mine can be classified as a variant of MVT-type deposit, whereas the Fe-Mn ore can be classified as a stratiform-syn-sedimentary deposit. The formation of the MVT-type deposit is associated with a hydrothermal fluid system with a mean temperature of 183<span style="white-space:nowrap;">°C and mean salinity of 12.85 wt. % NaCl equivalent. The syn-sedimentary Fe-Mn ore, which is largely associated with calc-silicate lithologies, consists mainly of magnetite and hematite with minor pyrite, hausmannite and jacobsite, and was deposited by diagenetic and mixed diagenetic-hydrogenetic processes under changing oxic and anoxic conditions within the sedimentary basin. Acceptable geochemical exploration indicators of the existing mineralization include anomalous values above 0.5% Cu, 0.2% S;0.05% Pb;0.04% As;0.01% Zn;V, W, Mo, and Ag are 0.002%. Mineralogical indicators include chalcopyrite, bornite, covellite and galena with minor chalcocite, sphalerite, and tennantite for the Cu-Pb MVT-type ores at Kombat Mine.
文摘The scientific objectives and research program of the IGCP-646 project(2015-2018)cuts across many disciplines and includes various aspects of continental basement geology,resource exploration(mineral,water and hydrocarbons),geohazard mitigation,and climate change,all of which are of critical importance to developing countries,particularly in parts of West Africa where population pressures are on the rise.Considerable emphasis was placed on capacity building,creation of opportunities for young scientists to undertake higher degrees programs,knowledge transfer and training.The SIDA-funded“pilot project”IGCP-616Y(started in 2012),focused on three objects(i)crustal architecture,tectonic evolution and regional geology of Central Africa and the connection with NE Brazil;(ii)the Mesozoic continental rifting and breakup leading to a better integration of the onshore and offshore geology;(iii)clarification and quantification of the links between basement structures,neotectonics,climate change and landscape evolution.The IGCP-616Y and IGCP-646 projects consisted of over 250 researchers,from different countries.In the course of the projects,six annual meetings,four field trips/workshops,as well as several training sessions were organized.Here we provide a summary of the scientific targets of the projects and a summary of the organized activities.
