Mineral Chemistry of REE-Rich Apatite and Sulfur-Rich Monazite from the Mushgai Khudag, Alkaline Volcanic-Plutonic Complex, South Mongolia  

作　　者：Dorjpalma Enkhbayar Jieun Seo Seon-Gyu Choi Young Jae Lee Enkhbayar Batmunkh Dorjpalma Enkhbayar;Jieun Seo;Seon-Gyu Choi;Young Jae Lee;Enkhbayar Batmunkh(Department of Earth and Environmental Sciences, Korea University, Seoul, Korea;Geological Investigation Center of Mongolia, Ulaanbaatar, Mongolia)

机构地区：[1]Department of Earth and Environmental Sciences, Korea University, Seoul, Korea [2]Geological Investigation Center of Mongolia, Ulaanbaatar, Mongolia

出　　处：《International Journal of Geosciences》2016年第1期20-31,共12页地球科学国际期刊（英文）

摘　　要：The Mushgai khudag volcanic-plutonic complex consists of four REE mineralization zones: carbonatite zone, apatite zone, magnetite zone, and monazite zone. REE mineralization occurs within peripheries of alkaline magmatic rocks which consist of porphyritic syenite, microsyenite and quartz syenites. Three types of LREE-rich apatite can be found in the carbonatite, apatite, and monazite zones. Crystal-1 type of apatite exists as hexagonal prismatic shape and is mostly found in the apatite zone, and in syenite. Crystal-2 type of apatite can be exposed also at the apatite zone, and carbonatite zone as brecciated massive crystalline aggregate. Crystal-3 type of apatite demonstrates the compositional zoning texture with monazite as inter-zoning, and is only found in monazite zone. The LREE-bearing apatites from the Mushgai khudag complex are mostly fluorapatite to hydroxyl-bearing fluorapatite with variable REE content. Apatites from the monazite zone present individual sulfur-rich monazite grain, and are formed by comprehensive substitutions.The Mushgai khudag volcanic-plutonic complex consists of four REE mineralization zones: carbonatite zone, apatite zone, magnetite zone, and monazite zone. REE mineralization occurs within peripheries of alkaline magmatic rocks which consist of porphyritic syenite, microsyenite and quartz syenites. Three types of LREE-rich apatite can be found in the carbonatite, apatite, and monazite zones. Crystal-1 type of apatite exists as hexagonal prismatic shape and is mostly found in the apatite zone, and in syenite. Crystal-2 type of apatite can be exposed also at the apatite zone, and carbonatite zone as brecciated massive crystalline aggregate. Crystal-3 type of apatite demonstrates the compositional zoning texture with monazite as inter-zoning, and is only found in monazite zone. The LREE-bearing apatites from the Mushgai khudag complex are mostly fluorapatite to hydroxyl-bearing fluorapatite with variable REE content. Apatites from the monazite zone present individual sulfur-rich monazite grain, and are formed by comprehensive substitutions.

关 键 词：FLUORAPATITE Hydroxyl-Bearing Fluorapatite Sulfur-Rich Monazite Mushgai Khudag 

分 类 号：P59[天文地球—地球化学]