摘要
选取纵贯宁芜北段东带范围内5条穿过主要矿床(点)和主要构造的NW向剖面,结合钻探、地质和矿床资料,对前人重磁数据进行二次开发,对剖面进行2.5D重磁联合反演。综合各剖面反演成果,编绘区内剖面立体示意图,认为与成矿关系密切的(辉石)闪长玢岩在研究区西部埋藏较浅,东部埋藏较深,中部隆起区中深部仍有隐伏岩体。通过解译认为赋矿地层黄马青组埋深由出露地表的隆起部位向北西向、南东向加深,且北西向加深趋势缓于南东向,该区重力异常对断裂的指示强于磁异常对断裂的指示。文章以图像化的方式展示宁芜北段东带的地质结构特征和基底空间分布特征,可为该区进一步找矿提供参考。
Based on a number of drilling,geological and ore data,five main NW-trending profiles crossing main deposits and structures in the eastern section of northern Ningwu were selected to conduct an integraged 2.5D inversion investigation using the previous gravity and magnetic data.Inversion results and schematic 3D diagram of the cross sections in the study area suggest that diorite porphyrite or pyroxene diorite porphyrite closely related to mineralization is buried shallower in west than in east.There is likely occurrence of hidden terranes in the deeper part of the central uplift area.Our interpretation for the results indicates that the depth of ore-bearing Huangmaqing Formation gradually increases from the outcropped central uplift zone to northwest and southeast,with depth increasing quicker in the northwest than in the southeast.Gravity anomoly in this areas is much distinctive for fault than magmatic anomoly.This study displays visually the characteristics of geological structure and spatical distribution of substrate in the eastern section of northern Ningwu,which can provide some reference for further prospecting work.
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