摘要
根据魁岐杂岩体的岩石类型、结构构造、形成的时间先后等,将其划分为4个单元:(1)晶洞黑云母钾长花岗岩;(2)晶洞中粗粒碱性花岗岩;(3)晶洞斑状碱性花岗岩;(4)晶洞细粒碱性花岗岩。由第1单元至第4单元其岩石化学组分及SI,FI,MF,AKI等参数值均呈有规律变化。岩石的∑REE值较高,锶同位素初始比值为0.7085,Rb-Sr等时线年龄为89.6Ma。Nd同位素研究表明,该岩体在形成时有70％～80％的的地幔物质加入。
On the basis of the rock type, texture and structure and formations age of the Kuiqi miarolitic granite batholith it is devided into 4 units:1) Miarolitic biotite-feldspar granite; 2) Medium-coase-grained mioroliticalkali-granite; 3) Porphyritic miarolitic alkali-granite; 4) Fine-grainedmiarolitic alkali-granite.The unit No.1→unit No. 4 follow a regular patternso far as the petrochemical composition, SI,FI, MF and AKI are concerned.The Rb-Sr isotope age of the batholith is 89.6 Ma. Its petrological,petrochemical, REE pattern and Sr, Nd isotope characteristics show thatKuiqi granites are formed as a result of the comprehensive process ofearly syntexis-type magma with late mantle-derived magma.
关键词
花岗岩
碱性
成因
岩石
地球化学
alkali-granite
miarolitic cavity
petrochemistry
geochemistry
rock genesis
Fujian
Kuiqi
