【作者】 林东燕；

【导师】 吴淦国； 陶建华；

【作者基本信息】 中国地质大学（北京） ， 构造地质学， 2011， 博士

【摘要】 闽西南地区是“永梅拗陷带”的重要组成部分,大地构造位置处于华夏古陆的主体、中国东部环西太平洋火山岩带以及多金属成矿带交汇处,是特提斯E-W向构造与环太平洋NE向构造时空演化交替的典型地区。在漫长的地质构造演化过程中,形成了福建省“东西分带,南北分块”的基本构造格局,同时也造就了该区良好的成矿地质条件和丰富的矿产资源,是我国铁等矿产重要的矿集区。本文将福建大地构造单元划分为武夷基底杂岩、闽西南被动陆缘与陆表海盆地以及闽东岩浆弧等3个Ⅲ级单元。其中,研究区所属的闽西南被动陆缘与陆表海盆地,可进一步划分武平桃溪基底杂岩、南口-清流陆内裂谷、长汀-上杭陆缘斜坡、大田-龙岩陆表海盆地等4个Ⅳ级单元。宁化-南平、政和-大埔、上杭-云霄、闽江口-永定等四条主要深大断裂带控制着区内沉积成矿作用及构造、岩浆的演化。研究区发育了印支和燕山二个期次的逆冲推覆构造。其中,印支期可分为明溪—上杭和南平—龙岩两个NE走向的推覆构造带,主要表现为自北西向南东的逆冲推覆;燕山期也可大致分为东部沿政和—大埔断裂带分布的推覆构造带和西部明溪—清流里田两个条带,整体表现为自东向西逆冲推覆。通过对晚古生代—三叠纪地层的沉积特征、岩相古地理和构造环境分析、探讨,得出了研究区晚古生代—三叠纪是特提斯E-W向构造重要的组成部分,推测晚古生代—三叠纪存在“闽东古陆”,提出了研究区晚古生代—三叠纪特提斯构造演化模式,并将区内演化划分为结晶基底形成、变质褶皱基底形成、陆表海盆地发育、活动大陆边缘等四个发展阶段。通过对马坑、汤泉典型铁矿床的解剖,认为马坑铁矿为沉积-改造型铁,汤泉铁矿为接触交代型。其中获得马坑热液叠加改造伴生辉钼矿Re-Os等时线年龄为130.5±0.92Ma。通过总结铁矿区域成矿条件及时空分布规律,提出了铁矿区域成矿模式及区域找矿标志,并划分了大田-将乐接触交代型铁矿区和龙岩-德化沉积-改造型铁矿区2个成矿亚带(Ⅳ级),以及将乐万安、永安溪南-大田龙凤场、大田银顶格、漳平挂山、德化阳山、安溪潘田-剑斗、龙岩蕉山-漳平大坂、漳平洛阳、龙岩马坑、上杭湖洋等10个铁矿成矿远景区(Ⅴ级)。并提出了远景区部署建议。更多还原

【Abstract】 The Southwestern Fujian Province is important part of the Yongmei depression belt, and its geotectonic location belongs to Cathaysia, also a part of the circum Pacific volcanic belt and polymetal metallogenic belt, which has undergone the transformation from Tethys to the circum-Pacific tectonic domain. The basic tectonic framework of“zoning in the E-W direction and blocking in the S-N direction”has been formed during long term geological evolution. At the same time the favorable metallogenic conditions and abundant mineral resources have been brought up in this area which has become the significant ore-concentrating place of iron and polymetal mineral resources in China.The Fujian Province is divided into three three-order tectonic units, i.e. the Wuyi basement complexes, the Southwestern Fujian passive continental margin and epicontinental basin and the Eastern Fujian magmatic arc in this paper. Among them the Southwestern Fujian passive continental margin and epicontinental basin can be further divided into four the forth-order units: Wuping-Taoxi basement complexes, Nankou-Qingliu intracontinental rift, Changting-Shanghang continental slope and Datian-Longyan epicontinental basin. Sedimentary mineralization and tecto-magmatic evolution within this area are controlled by Ninghua-Nanping, Zhenghe-Dapu, Shanghang-Yunxiao, Minjiangkou-Yongding four major deep fault zones. The two of Indosinian and Yanshanian periods of thrust nappe tectonic belts developed in the study area, of which the two of Mingxi - Shanghang and Nanping - Longyan Indosinian NE-trend nappe tectonic belts show thrusting from NW to SE. Yanshanian nappe tectonic belts also can be divided into two types: the eastern thrust nappe belt along Zhenghe-Dapu deep fault zone, and the western Mingxi-Qingliu thrust nappe belt demonstrate thrusting from east to west.Through analysing the late Paleozoic - Triassic sedimentary features, lithofacies palaeogeography and tectonic environment, it is obtained that the study area during late Paleozoic - Triassic is an important part of the E-W Tethyan tectonic domain, suggesting that there exists "the eastern Fujian ancient land " during Late Paleozoic- Triassic, and proposing the Late Paleozoic - Triassic Tethyan tectonic evolution model in the study area, which can be divided into four evolution stages: the formation of crystalline basement, the formation of metamorphic folded basement, the development of epicontinental basin and the active continental margin.By detailed study of the Makeng, TangQuan typical iron ore deposits, it is thought that the Makang iron ore deposit is the sedimentary and reformed deposit. And the Re-Os isochron age of the Makeng associated molybdenite superimposed by hydrothermal solution is 130.5±0.92Ma.By summarizing the regional metallogenic conditions and the temporal and spatial distribution regularities, the regional metallogenic model and iron ore prospecting indicators have been proposed, and two iron metallogenic subzones (four level) have been divided: the Datian-Jiangle contact metasomatic iron metallogenic area and Longyan-Dehua sedimentary-reformed iron metallogenic area, and the Jiangle-Wanan, Xinan in Yongan–Longfengchang in Datian, Yindingge in Datian, Guashan in Zhangping, Yangshan in Dehua, Pantian -Jiandou in Anxi, jiaoshan in Longyan- Daban in Zhangping, Luoyang in Zhangping, Makang in Longyan, Huyang in Shanghang 10 iron ore prospecting areas (the fifth level). Recommendations on the deployment of prospective areas have been put forward.更多还原