The Miaoya carbonatite complex, occuring as lens, is located west of Wudon massif,Hupch Province, and consists of carbonatites and syenites associated with them. The carbonatites arc corapositionally classified into f...The Miaoya carbonatite complex, occuring as lens, is located west of Wudon massif,Hupch Province, and consists of carbonatites and syenites associated with them. The carbonatites arc corapositionally classified into four types, i.e., sovite, alvikite, carbonbearing alvikitc and ankcritic carbonatite. Their average composition is in agreement with the abundance values for carbonatites compiled by Gokd (1966). Three stages can be recognized: the sevite and alvikite types are the earliest followed by carbonbearing alvikite type, while ankcritic carbonatite type is the latest. Some regularities are observed with respect to the distribution of major and rare elements during the evolution of carbonatites. For example, Nb is essentially enriched in sovite type.Except niobite and ilmenorutile, there are also pyrochlore, nioboesehynite and fersmite in it. RE is concentrated mainly in ankeritic carbonatite type, within which bastnasite,parisite and monazite are found. In general, Ca Nb, and Sr decrease, while Fe, Mg,Mn anal RE increase from earlier to later stages. It is suggested that the carbonatites were gew, geneticolly conneeted with syenitic magma.展开更多
文摘The Miaoya carbonatite complex, occuring as lens, is located west of Wudon massif,Hupch Province, and consists of carbonatites and syenites associated with them. The carbonatites arc corapositionally classified into four types, i.e., sovite, alvikite, carbonbearing alvikitc and ankcritic carbonatite. Their average composition is in agreement with the abundance values for carbonatites compiled by Gokd (1966). Three stages can be recognized: the sevite and alvikite types are the earliest followed by carbonbearing alvikite type, while ankcritic carbonatite type is the latest. Some regularities are observed with respect to the distribution of major and rare elements during the evolution of carbonatites. For example, Nb is essentially enriched in sovite type.Except niobite and ilmenorutile, there are also pyrochlore, nioboesehynite and fersmite in it. RE is concentrated mainly in ankeritic carbonatite type, within which bastnasite,parisite and monazite are found. In general, Ca Nb, and Sr decrease, while Fe, Mg,Mn anal RE increase from earlier to later stages. It is suggested that the carbonatites were gew, geneticolly conneeted with syenitic magma.
