东秦岭—大别造山带北侧构造变形研究

【作者】 邢翔；

【导师】 郭建秋；

【作者基本信息】 昆明理工大学 ， 构造地质学， 2009， 硕士

【摘要】 秦岭--大别造山带是中国扬子、华北两大板块的构造拼合带。东秦岭-大别造山带北侧是该区域的重要组成部分。研究该区域的构造特点,解析不同时期构造作用,重塑东秦岭-大别造山带北侧现今结构,确立纵向和横向构造变形的差异性,对于推动该地区盆山关系和地质找矿有着重要意义。本文在了解秦岭大别造山带及邻区最新研究进展的基础上,以活动论构造历史观为指导,综合应用构造学、岩石学和地球物理的方法,通过野外地质调查和室内综合地球物理资料的解释,得出如下结论。(1)根据主要构造界线和演化过程,以商南-信阳-舒城断裂和襄樊—广济断裂为界,将研究区划分为三个地块：华北地块、秦岭地块和扬子地块。其中,以灵宝-鲁山-确山-固始—肥东断裂带为界,将华北地块分为华北地块南部和华北地块本部,且在华北地块南部,栾川—方城—明港—肥西断裂再次将其分为北秦岭构造带和华北地块南缘构造带。(2)根据地层接触关系,以印支期界面为主要分界面,东秦岭—大别造山带北缘地区可分为三大构造层：盆地基底、盆地盖层和上覆层。其盆地基底为前印支构造层,盆地盖层可再分为印支期亚构造层、早燕山亚构造层、中燕山亚构造层、晚燕山—早喜马拉雅亚构造层、晚喜马拉雅亚构造层,上覆层为第四纪沉积物。作为研究主体的盆地盖层各亚构造层还可细分出系列次一级构造层。(3)通过确立研究区四条主干地质剖面：西峡—伊川剖面、桐柏—舞阳剖面、新县—光山剖面和六安—岳西剖面构造形变特征,搭建了区域地质格架(4)建立了研究区现今各结构单元的差异构造变形、变形样式和变形量的分析,明确了各构造单元的差异变形。更多还原

【Abstract】 Qinling-Dabie orogenic belt is the tectonic amalgamation belt of Yangtze plate and North China plate, of which the East Qinling-the northern margin of Dabie organic belt is the main component part. This paper studied the tectonic characteristics, analysed tectonic actions during different periods, remolded the current structure of the East Qinling-the northern margin of Dabie orogenic belt and established the differences between the vertical and horizontal tectonic deformation.It is of great value in making clear the relationship between the basin and the mountion in this region and geological prospecting.On the basis of systematically summing up the results of the previous research, under the guide of mobilism and tectonic history view, through the methods of tectonics,petrology and geophysics, field research and laboratory analysis, the Qinling-the north Dabie orogenic belt structural characteristics and tectonic evolution come to the following conclusions and awareness.(1) Compromise based on the regional geophysical characteristics in the study area, the important tectonic boundary is established by the Shangnan-Xinyang-Shucheng fracture, Luanchuan-Fangcheng-Minggnag-feixi fracture and Lingbao-Lushan queshan-Gushi-feidong crack band.According to the main tectonic boundaries and evolutionary processes to shangnan-Xinyang-Shucheng fault and Xiangfan-Guang Ji fault bounded, the study area are divided into three blocks:the North China block, Qinling block and Yangtze block, Among them, Lingbao-Lushan-queshan-Gushi-feidong fault zone is bounded, by which the North China block is divided into the southern North China Block and North China block headquarters, and in the southern of North China block, Luanchuan-Fangcheng-Minggang-feixi fault again divided into the North Qinling tectonic belt and the southern margin of North China block tectonic belt.(2) According to research stratigraphic contact, Indo-China as the main interface, the East Qinling-the northern margin of Dabie orogenic belt can be divided into three tectonic regions:the basement, basin cap rock and overlying layers, the basin basement shall be pre-Indo-China structural layer, while the basin cap rock can be further divided into sub-structural layer Indosinian early Yanshan tectonic sub-layer, in the Yanshan tectonic sub-late Yanshan-Early Himalayan sub-structural layer, late Himalayan sub-structural layer, Quaternary sediments overlying layer. As a research subject in the study area the sub-basin tectonic cap rock can be further divided into a series of less-grand structural layer.(3) The tectonic deformation features of four main geological sections are established in the study area:Xixia-Yichuan profile, Tongbai-Wuyang profile, Xinxian-Guangshan profiles and Liuan-Yuexi profile.(4) Through analysis the remnants stratigraphic distribution, tectonic chronology and rock fabric, balanced cross-section analysis, and paleo-stress analysis, established the research of differences in tectonic deformation, deformation styles and deformation analysis in the present-day structural unit, the differences in deformation of the various tectonic units are made clear.更多还原