地質(zhì)學(xué)

地質(zhì)學(xué)

來源出版物：SCIENCE CHINA Earth Sciences，2015，58（7）： 1045-1069聯(lián)系郵箱：ZHENG Yong-fei，yfzheng@ustc.edu.cn

哀牢山南段長安金礦地質(zhì)特征及找礦方法研究

李華，王永華，張星培，等

長安金礦位于哀牢山成礦帶南段，是該成礦帶上新近發(fā)現(xiàn)的又一大型金礦床。該區(qū)為哀牢山地體邊緣地殼增生帶，主要由深變質(zhì)巖系組成，區(qū)內(nèi)構(gòu)造斷裂發(fā)育，對巖漿活動和成礦作用有顯著影響。本文總結(jié)了長安金礦的地質(zhì)特征，并以該區(qū)的控礦斷裂F6為主要研究目標(biāo)，以地層巖性電性特征作為約束條件，分別展開了磁法、激電、瞬變電磁和大地電磁等綜合物探手段的試驗研究。研究結(jié)果表明，磁法對于該礦找礦效果不明顯，瞬變電磁和大地電磁測深反演的電阻率低阻體，準(zhǔn)確界定了控礦斷裂F6的位置、傾向、斷距以及深部延伸情況，通過激電異?？纱笾屡袛嗟V體的位置。所以在長安金礦區(qū)下一步的深部隱伏礦勘查中，結(jié)合瞬變電磁、激電、大地電磁等地球物理方法，輔以土壤化探異常進行約束，可以達到快速有效找礦之目的。

哀牢山；長安金礦；EH-4；深部構(gòu)造；瞬變電磁；激電

來源出版物：地質(zhì)學(xué)報，2015，89（6）： 1085-1098

聯(lián)系郵箱：李華，23841719@qq.com

封面介紹：The plate tectonics theory was originally developed from the study of continental drift，seafloor spreading and oceanic subduction，with little attention to continental tectonics. The discoveries of ultrahigh pressure metamorphic minerals in continental rocks resulted in the recognition that continental crust is subductable to mantle depths. More and more studies demonstrate that the plate tectonism may have generally evolved from oceanic subduction to continental collision，with some tectonic and geochemical inheritance from marginal tectonics to intracontinental tectonics. Intraplate magmatism may be viewed as post-subduction magmatism. Reworking of ancient and juvenile crustal rocks is a key to continental tectonics. For more details see review article by ZHENG YongFei et al. on pages 1045-1069.

Developing plate tectonics theory from oceanic subduction zones to collisional orogens

ZHENG Yong-fei，CHEN Yi-xiang，DAI Li-qun，et al.

Crustal subduction and continental collision is the core of plate tectonics theory. Understanding the formation and evolution of continental collision orogens is a key to develop the theory of plate tectonics. Different types of subduction zones have been categorized based on the nature of subducted crust. Two types of collisional orogens，i.e. arc-continent and continent-continent collisional orogens，have been recognized based on the nature of collisional blocks and the composition of derivative rocks. Arc-continent collisional orogens contain both ancient and juvenile crustal rocks，and reworking of those rocks at the post-collisional stage generates magmatic rocks with different geochemical compositions. If an orogen is built by collision between two relatively old continental blocks，post-collisional magmatic rocks are only derived from reworking of the old crustal rocks. Collisional orogens undergo reactivation and reworking at action of lithosphere extension，with inheritance not only in the tectonic regime but also in the geochemical compositions of reworked products（i.e.，magmatic rocks）. In order to unravel basic principles for the evolution of continental tectonics at the post-collisional stages，it is necessary to investigate the reworking of orogenic belts in the post-collisional regime，to recognize physicochemical differences in deep continental collision zones，and to understand petrogenetic links between the nature of subducted crust and post-collisional magmatic rocks. Afterwards we are in a position to build the systematics of continental tectonics and thus to developthe plate tectonics theory.

crustal subduction； continental collision； postcollisional reworking； magmatism； metamorphism； continental tectonics