海南岛晚海西-印支期埃达克质岩的构造环境判别及其对比  

Tectonic setting discrimination and its comparison for adakitelike rocks from the Late Hercynian to Indonsinian cycles, Hainan island

作　　者：高小卫[1] 吴秀荣[1] 杨振强[1] 

机构地区：[1]中国地质调查局武汉地质调查中心,武汉430205

出　　处：《华南地质与矿产》2014年第3期206-217,共12页Geology and Mineral Resources of South China

基　　金：印尼中苏门答腊岛铜金等多金属矿产成矿规律研究〔科(2011)01-71-14〕

摘　　要：本文采用岩浆岩石地球化学作图软件,处理了海南岛晚海西-印支期埃达克质岩以及钾玄质岩的岩石化学分析数据,目的在于探讨其形成构造环境。根据地球化学-构造环境判别图解,海南岛在海西-印支期属于火山-岩浆弧环境,并将其与隔海相望的印支陆块东侧和华南板块同构造旋回的埃达克质岩进行对比。对比结果表明:海南岛与长山带晚海西-印支期埃达克质岩具有相似的构造环境,主要为主动大陆汇聚边缘带,其次为碰撞后板内地壳伸展-减薄环境。而华南板块同期的埃达克质岩则为大陆板内陆-陆同碰撞成因,与陆内深大断裂的活动有关。This paper deals with the data of chemical analyses for the Late Hercynian-Indonsinian adakitic rocks in Hainan Island by using the geochemical software of processing igneous petrologic data, in order to discuss their tectonic setting. According to these diagrams of geochemical - tectonic setting discrimination, the authors recognize that Hainan Island belonged to Hercynian- Indonsinian volcano-magmatic arc environment, and that may be comparable with the adakitic rocks adjacent to eastern margin of Indochina Continental Plate as well as Southern China Plate within the same tectonic cycle. The result of the comparison indicates that the Late Hercynian-Indonsinian adakitic rocks in Hainan Island and Truong Son belt have the similar tectonic setting. All of them are the main products of convergent belt at active continental margin, also have evidences to show that the minor affect by the extension and attenuation of crust after post-collision. By contraries, the adakitic rocks of the same cycle within Southern China Plate, however, belong to igneous rocks caused by continent-continent collision, and have their origin related to deep fault activities.

关 键 词：海南岛 晚海西-印支期 地球化学-构造环境 埃达克质岩 

分 类 号：P588.1[天文地球—岩石学]