江西广丰岭底早白垩世破火山口地质和地球化学特征及其构造意义  

Geological characteristics and their tectonic significance of early Cretaceous Lingdi caldera in Guangfeng county,Jiangxi Province

作　　者：唐春花[1] 张福神[1] 张旭[2] 陈辉明[3] 向忠金[3] 

机构地区：[1]江西省地质调查研究院,南昌330030 [2]河北地质职工大学,石家庄050081 [3]中国地质科学院地质研究所,北京100037

出　　处：《资源调查与环境》2013年第2期80-88,共9页Resources Survey & Environment

基　　金：国家地质调查项目:扬子东南缘中生代盆地充填序列与构造成矿事件研究项目(No:1212011085415)资助

摘　　要：本文对江西广丰岭底早白垩世破火山口进行了全面研究,选择军潭山—岭底实测火山旋回地质剖面作为该火山口基准剖面,厘定了该火山机构早白垩世中墩组第三旋回火山岩地层及其与晚期火山活动侵入的花岗斑岩的关系,划分了火山岩岩相类型、组合;对基准剖面采集样品进行测试分析,通过地层、岩相、岩石学及地球化学等方面的研究,讨论了火山岩相与火山喷发类型的成因机制,探讨了母岩浆性质、起源及火山—侵入作用的构造环境。研究认为,岭底火山岩为铝质A型流纹岩,形成于以挤压为主并转向拉张的构造环境,为进一步研究铜钹山花岗质火山—侵入杂岩及区域岩浆构造演化提供了地质依据。The early Cretaceous Lingdi caldera in Guangfeng county, Jiangxi Province, is studied in this paper, taking the Juntanshan-Lingdi measured geological profile as the key section, and the volcanic sequence of the third subcycle of Zhongdun Formation volcanic cycle porphyries are defined, and the types and combi- nations of volcanic lithofacies are devided. By studying on the strata, lithofacies, petrology and geochemis- try of the samples from the key section, the genesis mechanism of volcanic facies and types of volcanic e- ruptions are discussed and the tectonic environment of volcanism-intrusion are approached. It is considered that the Lingdi volcanic rocks belong to aluminous A-type rhyolites, formed in an environment of compression transforming to tension, providing geological evidences for studying on Tongbashan granitic volcanicintrusive rocks and their regional magmatic tectonic evolution.

关 键 词：火山机构 火山岩相 地球化学 广丰岭底 江西 

分 类 号：P588.1[天文地球—岩石学]