摘要
周潭群变质岩中石榴石、斜长石和黑云母微区化学成分变化明显 ,石榴石变斑晶具典型的生长环带 ,由晶体中心向两侧边缘XMg、XFe值以光滑曲线递增 ,XCu、XMn值以光滑曲线递减 ,反映其增温过程 ;晶体最边缘的化学成分反映变质峰期的温度条件。通过石榴石变斑晶生长环带剖面分析 ,应用Grt_Bi温度计和GASP压力计 ,确定本区变质作用 pT轨迹为顺时针形式 。
The microarea compositional variations of garnet, plagioclase and biotite in Zhoutan Group show obvious regularity. Garnet displays typical growth zoning, which reflects the crystallization and growing process of garnet. The contact edge compositions of the coexisting Grt, Bi and Pl should reflect the temperature and pressure of the peak metamorphic stage. On the basis of garnet zoning and Grt-Bi geothermometry as well as GASP barometry, it is known that the pattern of the metamorphic pT paths is of the clockwise type, and that metamorphism must have taken place in the tectonic environment of continental collision zone.
出处
《岩石矿物学杂志》
CAS
CSCD
北大核心
2004年第4期337-345,共9页
Acta Petrologica et Mineralogica
基金
国家自然科学基金资助项目 (4 0 2 72 0 38)
科技部攀登计划预选项目 (95_预_39)
南京大学内生金属矿床成矿机制研究国家重点实验室开放基金资助项目
