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通过地面地质调查、样品分析测试以及前人资料收集利用,全面查明了区内地层、岩浆岩和构造发育特征,系统总结了区内矿产资源概况和成矿地质条件。针对有关区域地质问题进行了深入研究,取得以下主要进展及成果:确定了南华系—寒武系中砂岩的主量元素和微量元素特征,反映其形成于被动大陆边缘环境;确定了中三叠世后期印支运动表现为NWW—SEE向区域挤压下的陆内俯冲造山,提出了印支运动中NW向基底隐伏断裂的左行走滑导致部分地区构造线走向偏转,炎陵—汝城一带发育的印支期隔槽式褶皱形成于基底(厚皮式)横向收缩与压扁作用;确定了中生代印支期、燕山早期和燕山晚期3阶段花岗岩的时限分别为233~210 Ma、174~135 Ma、130~85 Ma,形成构造环境分别为后碰撞、后造山和陆内裂谷;通过热年代学分析揭示了湘东南地区中、新生代山体隆升过程;厘定出湘东南及湘粤赣边区中生代构造发展框架;分析表明构造体制差异可能是造成湘东南燕山早期花岗岩成矿能力强于印支期花岗岩的关键原因,燕山早期钨锡多金属和铅锌多金属2类矿床组合的形成可能主要与岩石圈结构和深部热扰动强度有关。
Through the surface geological survey, sample analysis and testing, as well as the collection and utilization of previous data, the stratigraphy, magmatic rocks and tectonic development characteristics of the area have been comprehensively identified. The general situation of mineral resources and the geological conditions of mineralization in the area have been systematically summarized. In-depth study on the relevant regional geological problems, made the following major progress and achievements: The main elements of the South China-Cambrian sandstone and trace element characteristics, reflecting the formation in the passive continental margin environment; identified in the Triassic The Indosinian movement of NW China was manifested by intracontinental subduction NWW-SEE squeezed into the region. It is proposed that left-lateral strike-slip of NW-trending basement buried faults in the Indosinian movement resulted in the tectonic line deflection in some parts of the Yanling-Rucheng area The developed Indosinian interval folds formed in the basement (thick skin) lateral shrinkage and crushing. The time limits of Mesozoic Indosinian, Early Yanshanian and Late Yanshanian granites were 233 ~ 210 Ma and 174 ~ 135 Ma and 130-85 Ma respectively. The tectonic environment was post-collisional, post-orogenic and intracontinental rift respectively. The uplifting processes of Mesozoic and Cenozoic mountains in southeastern Hunan were revealed by the analysis of thermal geochronology. The analysis shows that the difference of tectonic regimes may be the key reason that the early Yanshanian granite in the southeastern part of Hunan Province was stronger than that of Indosinian granite. Formation of Pb-Zn polymetallic Group 2 deposits may be mainly related to lithosphere structure and deep thermal disturbance intensity.