目前,科西斯坦島�。↘IA）西南部的年代學和Hf同位素的研究資料較為缺乏。為了解析KIA西南部（斯瓦特谷）的地質(zhì)過程,本次研究旨在解釋這些巖漿的分離和演化過程的問題,進一步揭示Metaplutonic雜巖體和上覆或侵入的Chilas雜巖體的成因聯(lián)系。此次研究方法主要包括巖相學、全巖地球化學、鋯石的U-Pb定年和配套的地球化學（微量元素和Hf同位素）。鋯石的年代學結(jié)果有助于約束地球深部的動力學過程,而微量元素則對巖石的成因及其形成環(huán)境提供有力的證據(jù)。鋯石的原位Hf同位素通過激光刻蝕-多接收電感耦合等離子質(zhì)譜儀（LA-MC-ICPMS）分析測試完成,且獲得的Hf同位素較好地解釋了源于地幔的大陸地殼的生長。此外,鋯石的Hf同位素也很好地刻畫了各巖漿源區(qū)的細微差異。研究顯示,這兩個雜巖體的形成年齡為83-87 Ma,ε_Hf（t）值的范圍為-6.82-+11.9。Metaplutonic雜巖體的鋯石ε_Hf（t）值介于-6.8⁺10.1之間,表明了其可能受到俯沖作用的影響。而Chilas雜巖體的ε_Hf（t）值的... 

【文章來源】：中國地質(zhì)大學(北京)北京市211工程院校教育部直屬院校

【文章頁數(shù)】：107 頁

【學位級別】：碩士

【文章目錄】：
摘要
Abstract
1. INTRODUCTION
    1.1. General Statement
    1.2. Swat District
    1.3. Location of the study area
    1.4. Topography and Climate
        1.4.1. Flora and Fauna
        1.4.2. Agriculture and Associated Zones
    1.5. Previous Geological Work
    1.6. Aims and Objectives of the present study
    1.7. Work done in Present Thesis
2. REGIONAL TECTONICS
    2.1. Geological Setting and Background
        2.1.1. Northern Suture Zone (NSZ) or Main Karakoram Thrust (MKT)
        2.1.2. Kohistan Island Arc (KIA)
        2.1.3. Yasin Sedimentary Group
        2.1.4. Chalt Volcanic Group (CVG)
        2.1.5. Kohistan Batholith
        2.1.6. Dir Group
        2.1.7. Chilas Complex
        2.1.8. Metaplutonic Complex (Kamila Amphibolite)
        2.1.9. Jijal Complex
        2.1.10. Indus Suture Zone (ISZ) or Main Mantle Thrust (MMT)
    2.2. Geology of the study area
        2.2.1. Amphibolite
        2.2.2. Metagabbro
        2.2.3. Metagranodiorites
        2.2.4. Gabbronorite
        2.2.5. Ultramafic to Mafic Rocks
3. METHODOLOGY
    3.1. Field Work
    3.2. Thin Section Preparation
    3.3. Whole Rock Major and Trace Element
    3.4. Zircon Cathode luminescence (CL) images
    3.5. Zircon U-PB Dating and Hf isotopes
4. PETROGRAPHY AND GEOCHEMISTRY
    4.1. Petrography
        4.1.1. Amphibolites
        4.1.2. Metagabbro
        4.1.3. Metagranodiorite
        4.1.4. Gabbronorite
    4.2. Geochemistry
        4.2.1. Whole Rock Geochemistry
        4.2.2. The Metaplutonic Complex
        4.2.3. Chilas Complex
            4.2.3.1. Chilas Complex petrotectonic characteristics
5. GEOCHRONOLOGY AND HF ISOTOPES
    5.1. U-Pb and Hf isotopic results of Metaplutonic Complex
    5.2. U-Pb and Hf isotopic results of Chilas Complex
6. DISCUSSION AND CONCLUSION
    6.1. Arc magmatism sources
    6.2. Intra-oceanic arc crustal formation
    6.3. Geodynamic associations of the KIA
        6.3.1. Arc related intermediate to ultramafic plutons geochemical characteristics
        6.3.2. Petrogenesis of calc-alkaline magmatism from subduction environments
7. CONCLUSION
ACKNOWLEDGEMENT
REFERENCES
CURRICULUM VITAE (CV)



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