摘要
本文通过对广西大宁花岗闪长岩体及其中的暗色微粒包体的岩石学、微量元素及稀土元素地球化学、Rb—Sr同位素及微量元素初始比值等研究,认为该岩体中的暗色微粒包体属于幔源物质,同时提出了包体与主体花岗岩成因的上地幔—地壳相互作用模式,强调了花岗岩浆形成过程中系统的开放性及上地幔基性岩浆参与的重要性。
The evidence from the petrology , geochemistry of rare earth and trace elements , Rb-Sr isotopes and initial ratio of trace elements has revealed that the dark-colored microgranular enclaves (DCME) had derived from the upper mantle , being the fragments of broken lamprophyric or contaminated basaltic dykes which were solidified from the basaltic magma under rapid cooling rate through fractional crystallization . A genetic model , called upper - mantle - crust interaction model has been proposed to explain all the observed characteristics of the DCME and their host granodiorites , in which it is emphasized that the interference of basic magma from the upper mantle is essential for the melting of the sialic crustal rocks to produce granitic magma and DCME in the open - system magmatic process . The hypothetical model diifers from the genetic theory of granites and their included enclaves established on the hypothesis of closed system by White & Chappell (1977) and Chappell et al. (1987).
出处
《地球科学（中国地质大学学报）》
EI
CAS
CSCD
北大核心
1991年第4期377-386,共10页
Earth Science-Journal of China University of Geosciences
关键词
花岗岩
闪长岩
微量元素
稀土元素
granodiorite , dark -colored microgranular enclave , trace element, rare earth element , genetic model, Guangxi Province .
