霓长岩化矿物晶体化学和霓长岩化作用的研究

Amphibole is one of the most complex rock-forming minerds. More than five hundreds fenitic amphiboles have been studied in the present study. The study has found that the fenitic amphibole is one knid amphibole rich in magnesium, fluorine and potassium. The species of fenitic amphiboles depend on fenitizing fluid and country rock. The fenitic amphiboles of felsic country rock are mainly alkali- and sodic-calcic amphiboles, while mafic country rock calcic amphiboles. Most fenitic amphiboles are described by using the prefix magnesio-, and with Mg2+ / (Mg2++Fe2+) ＞0.5. The common names of fenitic amphiboles are magnesio-arfvedsonite and magnesio-riebeckite. We have found the crystal chemistries of fenitic amphiboles are exceedingly rich in fluorine and potassium, which are uncommon in the amphibole group of minerals. The F-, K+ and Mg2+ are interrelated in the cryseal chemistries of fenitic amphiboles. The fenitic amphiboles possess unique crystal chemistries,F-=OH-, Mg2+=Fe2+(Mn2+), K++Mg2+=Fe3+(Al3+), 2K++Mg2+=Ti4+ and K++Na+=Ca2+,which should result from the fenitizing fluids and carbonatite magmas. The studies of Mossbauer spectra have shown that Fe2+ site occupancies of fenitic amphiboles are M1＞M3＞M2. We have found the typical appearances of fenitization in the Bayan Obo REE-Fe-Nb deposit, which mean that the genesis of Bayan Obo REE-Fe-Nb deposit should be related to the carbonatite magnatism and fenitization.

研究霓长岩化矿物的共生组成；用电子探针和穆斯堡尔谱研究霓长岩化矿物晶体化学；用全岩分析和ICP分析研究霓长岩化作用中化学成分和稀土铌钽的演变；用包裹体和拉曼光谱研磕蕹ぱ一娜芤旱男灾省０涯蕹ぱ一笪锖湍蕹ぱ一睦砺垡牍冢⒄∽鞒龉仕降难芯砍晒