混杂岩基本特征与专题地质填图  

Characteristics and thematic geological mapping of mélanges

作　　者：闫臻[1] 王宗起[2] 付长垒[1,2] 牛漫兰[3] 计文化[4] 李荣社[4] 祁生胜 毛晓长[6] YAN Zhen;WANG Zongqi;FU Changlei;NIU Manlan;Jl Wenhua;LI Rongshe;QI Shengsheng;MAO Xiaochang(Institute of Geology,Chinese Academy of geological Sciences,Beijing 100037,China;Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China;Department of Resources and Environment,Hefei University of Technology,Hefei 230009,Anhui,China;Xi'an Center of Goloyical Survey,China Geologcal Survey,Xi'an 710054,Shaanxi,China;Qinghai Geological Survey,Xining 810001,Qinghai,China;China Geologcal Survey,Beijing 100037,China)

机构地区：[1]中国地质科学院地质研究所,北京100037 [2]中国地质科学院矿产资源研究所,北京100037 [3]合肥工业大学资源与环境工程学院,安徽合肥230009 [4]中国地质调查局西安地质调查中心,陕西西安710054 [5]青海省地质调查局,青海西宁810001 [6]中国地质调查局,北京100037

出　　处：《地质通报》2018年第2期167-191,共25页Geological Bulletin of China

基　　金：中国地质调查局项目<秦祁昆结合部构造事件调查及增生杂岩带专题填图试点>(编号:DD20160201-04);国家自然科学基金项目<拉脊山早古生代海沟-岛弧体系演化研究>(批准号:41672221)

摘　　要：混杂岩是造山带内最常见的地质体和最基本的大地构造相单元,是由多种地质作用共同形成的可作为一定比例尺(1∶25000或更大)的地质填图单元,并由块体和基质共同构成的内部无序的岩石混杂体。混杂岩的形成和就位构造环境不一致,并非所有混杂岩都具有古板块构造格局指示意义。蛇绿混杂岩和增生杂岩可作为古洋盆和汇聚板块边界的直接判别标志,其结构、组成与时空配置共同记录了古大洋板块地层系统发展及大陆地壳侧向与垂向增生历史。以大洋板块地层、海山理想层序和蛇绿岩"彭罗斯"层序模型为指导,专题地质填图是揭示造山带蛇绿混杂岩和增生杂岩结构、组成及其时空配置关系与形成机制的有效手段。这可为洋-陆转换研究及提高造山带结构深化认知程度提供直接证据,同时指导混杂岩相关矿床勘探与找矿预测。Mélange is the commonest geological body and the most fundamental tectonic facies of the orogenic belt around the world.It represents a mappable(1:25000 or more)geological unit formed by multiple geological processes and consists of blocks and matrix showing high stratigraphic disruption and a chaotic internal structure.The formation environment of mélanges is unequal to their emplacement environment,and hence not all of the mélanges were formed around the plate boundary reflecting plate tectonics.Ophiolitic mélanges and accretionary complexes can be used as the direct discriminating marks of ancient oceanic basin and convergent plate boundaries,and their texture and composition as well as spatial and temporal relationship have coevally recorded the development of oceanic plate stratigraphy and the lateral and vertical growth of the continental crust.On the basis of an ideal model of oceanic plate stratigraphy(including seamount)and Penronse ophiolite sequence,thematic geological mapping is the most effective way to clarify the texture and composition,spatial and temporal relationship,and formation mechanism of mélanges.The data obtained can provide direct evidence for reconstructing ocean-continental framework and improving our knowledge on the texture of orogenic belts,and can also guide mineral deposit exploration and ore prospecting plan.

关 键 词：造山带 混杂岩 蛇绿混杂岩 增生杂岩 专题地质填图 

分 类 号：P58[天文地球—岩石学]