摘要
大坝岩体属于南岭花岗岩。侵位于北东向和平复式背斜东翼的寒武纪浅变质岩系,与围岩呈明显的侵入接触。岩性为似斑状黑云母花岗岩,属碱质含量高、富钾、铝过饱和的酸性岩石。岩体形成温度550—730℃,水气压700bar,氢逸度10.37bar,氧逸度10^(17)atm,水逸度532.41bar。成因类型属陆壳改造型。
The Daba mass belongs to the Nanling granites. Obvious intrusive contact is observed between the Cambrian epimetamorphic rock system intruding into the eastern flank of the NE Heping anticlinorium and surrounding rocks. The Daba mass consists of porphyritic biotite granite with a chemical formula of K58Na49Ca19Mg17Fe19+2Fe3+3Al160Ti4Si622P3O1592OH8. It is a alkali-high, potassium-rich and aluminium-supersaturated acidic rock. Its formation temperature falls within the range of 550-730℃, barometic pressure 700 bars, hydrogen fugacity 10.37 bars, oxygen fugacity 10-17 atm, and water fugacity 532.41 bars. The Daba mass is of continental crust-transformed origin.
出处
《地球化学》
CAS
1987年第2期132-140,共9页
Geochimica
