摘要
地质时代置于晚震旦—寒武纪的“稻香组”主要出露于政和城关南面、稻香、铁山等地。根据这套变质岩系岩石共生组合、岩石化学、微古生物和稳定同位素及其 Sm—Nd 同位索模式年龄(T_(DM)^(ND)800±50Ma,作者认为:“稻香组”应属于早震旦世中基性火山—碎屑沉积建造的东岩组。根据稀土元素和 Sm—Nd 同位素地球化学资料分析,该套变质中基性火山岩岩源来自壳幔混合分离结晶作用的产物,是早震旦世华南海域火山喷发—钙硅碎屑沉积建造的重要组成部分。
“Daoxiang Formation”,which geological time was thought to be accordant with late Sinian-Cam-brian,mainly emerges in Zhenghe,Daoxiang,Tieshan and so on.On the basis of the paragenetic associ-ation of rocks,petrochemistry,micropalaeontology,stable isotope and Sm-Nd isotopic model ages(T_(DM)^(Nd),800±50Ma.)of this set of low-grade metamorphic rock series,authors consider that “DaoxiangFormation” should belong to Dongyan Formation (intermediate-basic volcanic-fragmental sedimentaryformation) of early Sinian.According to the information about rare earth element and Sm-Nd isotopicgeochemistry,it can be believed that source rock of this series of metamorphic intermediate-basic vol-canic rocks is resulted from the products of crust-mantle mixing fractional crystallization and is an im-portant constitution of volcanic eruption-calcic-silica fragmental sedimentary formation of early Sinianin sea area of South China.
出处
《福建地质》
1990年第4期266-280,共15页
Geology of Fujian
