峨眉山玄武岩研究史与地幔柱学说
投稿时间:2015-10-15  修订日期:2016-03-24  点此下载全文
引用本文:
DOI:
摘要点击次数: 475
全文下载次数: 
作者单位E-mail
蔡克勤 中国地质大学北京地球科学与资源学院 lsym@cugb.edu.cn 
陈宝国 中国地质大学北京地球科学与资源学院  
员雪梅 中国地质大学北京地球科学与资源学院  
林善园 中国地质大学北京地球科学与资源学院  
葛文胜 中国地质大学北京地球科学与资源学院  
穆星潼 中国地质大学北京地球科学与资源学院  
中文摘要:峨眉山玄武岩分布面积达30万km2,最大厚度5384m。自1928年赵亚曾创建“峨眉山玄武岩系”后,成为川滇黔地区独立的岩石地层单元出现在各类地质图件中。区域地质研究表明,本区玄武岩喷溢位于扬子地台西部大陆,以巨量的溢流玄武岩为主,玄武岩全岩K—Ar法年龄237~219Ma,即火山喷溢始于早二叠世,延续至晚二叠世。区域上自东向西可划分为三个岩区:Ⅰ、东部岩区,玄武岩岩石化学特征为下部地壳型;Ⅱ、中部岩区,称为攀西裂谷双峰式火山岩套,为受陆壳混染的壳幔型;Ⅲ、西部岩区为幔源型。玄武岩区厚度中心和陡变带走向均与主要深大断裂带一致,呈多中心裂隙式喷溢。本区地壳——上地幔综合地球物理研究证实,攀西裂谷位于康滇幔隆区之上,是地壳厚度减薄地带,上地幔顶部存在一层厚12~22km、P波速度7.6~7.8km/s的低速、低密度、低电阻的异常地幔显示。峨眉山玄武岩区的地质演化史,玄武岩系的岩石学、地球化学和地球物理学资料均表明,本区是古地幔柱活动区。梳理峨眉山玄武岩的研究历史,反映出我国地质学者,正在参与当代系统地球科学关注的热点和前沿课题——地幔柱学说的研究行列,正在开拓地幔柱及其成矿作用的新领域。
中文关键词:峨眉山玄武岩  构造环境  地质演化  地幔柱  成矿作用
 
The study on the Emeishan Basalt and theory of Mantle plume
Abstract:The study on the Emeishan Basalt and theory of Mantle plume Cai Keqin, Chen Baoguo, Yun Xuemei, Lin Shanyuan, Ge Wensheng ,Mu Xingtong School of Earth Science and Resources, China University of Geosciences(Beijing) , Beijing 100083 Abstract: Emeishan Basalt covers about 300,000 square kilometers with the maximum thickness up to 5384 m. Since Zhao Yazeng has created “Series of Emeishan Basalt” in 1928, the basalt of Emeishan Basalt became independent lithostratigraphic unit area of Sichuan, Yunnan and Guizhou provinces in China and appeared in all types of geological maps. Regional geology research indicates that the basalt eruption ocurred in the Yangtze platform in western China, giving priority to with a huge amount of overflow basalt. The whole rock has ages of 219 ~ 237 Ma by the K-Ar method, suggesting that the volcanic eruption began in the early Permian, and continued till the late Permian. The whole Emeishan Basalt can be divided into three areas from the east to the west: the basalt rock in east area has the chemical characteristics of the lower crust; middle rock area, known as the Panxi Rift bi-model volcanic set, was crust-mantle type because of the continental crustal contamination; the rock in the west area has the chemical characteristics of the mantle source type. The center of the thickness and direction changes of basalt area is consistent with the main deep fault belt. Integrated geophysical studies of earth's crust and mantle confirm that the Panxi Rift is located on the Kang-Dian uplift plume area and is the thinning crust belt. The top of the upper mantle in this area has a thickness of 12 ~ 22 kilometers, with P wave speed of 7.6 ~ 7.8 km/s, low speed, low density and low resistance of abnormal mantle shows. Based on the studies of the geological evolution, petrological, geochemical and geophysical data of the whole basalt series, it is concluded that the Emeishan Basalt area can be classified as an ancient mantle activity area. Studying, analyzing and summarizing the research history of Emeishan Basalt is effectively conducted by the Chinese geologists. This situation also suggest these geologists participate the study of mantle plume, which is a modern hot spot and frontier topic issue in the world and will open up a new field of mantle plume and its related mineralization. Key words: Emeishan Basalt; tectonic setting; geological evolution; mantle plume; mineralization
keywords:Emeishan Basalt  tectonic setting  geological evolution  mantle plume  mineralization
  查看/发表评论  下载PDF阅读器
版权所有 《地球学报》编辑部 Copyright©2008 All Rights Reserved
主管单位:国土资源部 主办单位:中国地质科学院
地址: 北京市西城区百万庄大街26号,中国地质科学院东楼317室 邮编:100037 电话:010-68327396 E-mail: diqiuxb@126.com
技术支持:东方网景