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Ore Geology Reviews, 2019
The late Mesoproterozoic Ngualla carbonatite complex in southwest Tanzania comprises a central magnesiocarbonatite plug surrounded sequentially by an annular calcite carbonatite intrusion and fenitised felsic igneous country rocks.
W. Witt, D. P. Hammond, M. Hughes
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The late Mesoproterozoic Ngualla carbonatite complex in southwest Tanzania comprises a central magnesiocarbonatite plug surrounded sequentially by an annular calcite carbonatite intrusion and fenitised felsic igneous country rocks.
W. Witt, D. P. Hammond, M. Hughes
exaly +2 more sources
Ore Geology Reviews, 2019
The Early Mesozoic Huanglongpu and Huangshui’an carbonatites in the Lesser Qinling Orogen are unique as they are associated with economic molybdenite mineralization and relatively enriched in heavy rare earth elements (HREE) compared to typical ...
Tian Bai, Wei Chen, Shaoyong Jiang
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The Early Mesozoic Huanglongpu and Huangshui’an carbonatites in the Lesser Qinling Orogen are unique as they are associated with economic molybdenite mineralization and relatively enriched in heavy rare earth elements (HREE) compared to typical ...
Tian Bai, Wei Chen, Shaoyong Jiang
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Geological Society of America Bulletin, 1956
The carbonatites are essentially carbonate-silicate rock with a great variety of other minerals. In this review the writer stresses the field and geochemical relationships of the carbonatites and alkalic igneous rocks and concludes that carbonatites were deposited by carbonatic solutions having a wide range of temperature, pressure, and concentration ...
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The carbonatites are essentially carbonate-silicate rock with a great variety of other minerals. In this review the writer stresses the field and geochemical relationships of the carbonatites and alkalic igneous rocks and concludes that carbonatites were deposited by carbonatic solutions having a wide range of temperature, pressure, and concentration ...
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Alkalic Rocks and Carbonatites
1972Alkalic rocks and carbonatites are among the rarest igneous rock-types. They tend to occur in stable platform areas and in Precambrian shields, rather than in orogenic belts. Barker (1969) estimated that in North America, alkalic rocks occupy a total surface area of only about 1500 square miles, and Heinrich (1966) concluded that the worldwide areal ...
Gunter Faure, James L. Powell
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Geological Curator, 2014
Geological material is the most chemically diverse of all types of natural history collections. Each mineral assemblage will require a specific set of environmental parameters to ensure stability. Unfortunately these are not yet fully understood and it is widely recognised that there is no environmental condition which will be suitable for all.
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Geological material is the most chemically diverse of all types of natural history collections. Each mineral assemblage will require a specific set of environmental parameters to ensure stability. Unfortunately these are not yet fully understood and it is widely recognised that there is no environmental condition which will be suitable for all.
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FENITES ASSOCIATED WITH CARBONATITES
The Canadian Mineralogist, 2008A review of occurrences of potassic and sodic fenitization around carbonatites is presented, including several new examples and oceanic ones. Taken in conjunction with the many examples quoted in the literature, conclusions are drawn that the K and Na contents of carbonatitic melts that induce fenitization are primary constituent parts of both ...
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CARBONATITE VOLCANOS OF EAST AFRICA AND THE GENESIS OF CARBONATITES
International Geology Review, 1985Yu. L. Kapustin, A. I. Polyakov
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Carbonatite-Alkaline Magma Immiscibility Conducing to Carbonatite REE Enrichment
2018Carbonatite is a particular type of magmatic rocks enriched in REE relative to the majority of igneous rocks. Among the numerous carbonatites referenced worldwide, only a few of them contain economic REE concentrations widely considered as resulting from late- to post- magmatic processes.
Nabyl, Zineb +6 more
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