摘要
罗源鉴江火山喷发盆地是福建东部晚中生代较为重要的火山喷发盆地之一,通过系统剖面测制、地质填图及采样测试分析,将盆地火山岩相划分为5种类型,并圈定了12个V级火山机构。通过对分布于盆地中的火山岩岩石地球化学分析,认为早白垩世黄坑组为分异程度中等偏高,属于过铝质中-高钾钙碱性岩系列的安山质-英安质-流纹质岩石组合;寨下组为一套分异程度中等偏高,属于过铝质中-高钾、钙碱-碱性岩系列的流纹质-粗面(英安)质岩石组合。研究区黄坑组原始岩浆主要来自下地壳和上地幔,而寨下组岩浆则主要来自中-下地壳,并有少量地幔物质的参与,成因均与板块俯冲作用有关。
Luoyuan Jianjiang volcanic eruption basin is one of the most important volcanic eruption basins in the late Mesozoic in eastern Fujian.Through systematic profile measurement,geological mapping and sampling test and analysis,the basic volcanic facies was divided into 5 types,and 12 grade V volcanic mechanisms were delineated.According to the geochemical analysis of the volcanic rocks distributed in the basin,it is considered that the differentiation degree of the early Cretaceous Huangkeng group is moderately high and belongs to The andesite-Dactylitic rhyolitic rock association of peraluminous medium-high potassium calc alkaline rock series.The Zhaixia Formation is a set of medium-high degree of differentiation,belonging to the peraluminous medium-high potassium,calc-alkali-alkaline series of rhyolitic-trachytic(dacite)rock assemblage.The original magma of Huangkeng Formation in the study area is mainly comes from the lower crust and upper mantle,while the magma of Zhaixia Formation mainly comes from the middle-lower crust with a small amount of mantle material,and the genesis is related to plate subduction.
作者
吴久芳
Wu Jiufang(The Western Geological Party of Fujian,Xiamen,361000)
出处
《福建地质》
2024年第1期28-42,共15页
Geology of Fujian
关键词
火山喷发盆地
火山作用
地球化学
罗源鉴江
volcanic eruption basin
volcanism
geochemistry
Jianjiang area of Luoyuan county
