(中南工業(yè)大學(xué)地質(zhì)研究所, 長沙 410083)
摘 要: 著重探討了瀾滄老廠銀鉛礦田基本構(gòu)造特征,對礦田內(nèi)發(fā)育的褶皺構(gòu)造、斷裂構(gòu)造、推覆構(gòu)造、滑脫構(gòu)造、基底(斷裂)構(gòu)造和火山構(gòu)造等進行了較為全面的論述;首次提出了該區(qū)存在較大規(guī)模的滑脫構(gòu)造,并對其特點、形成機制及其與成礦的關(guān)系作了深入的探討,解決了該礦田長期以來懸而未決的成礦構(gòu)造問題。針對該礦床存在三種不同類型的礦體群,從控礦構(gòu)造的角度出發(fā),分別論述了不同時代、不同類型和不同層次的構(gòu)造對礦體的控制作用。運用大比例尺遙感技術(shù),對該區(qū)的火山機構(gòu)進行解譯和精確定位,首次提出在老廠地區(qū)存在一個大型火山活動中心-老廠火山洼地,老廠礦床受大型火山洼地中次級噴火口控制的觀點。最后,從構(gòu)造演化歷史出發(fā),對構(gòu)造與成礦的關(guān)系作了較為系統(tǒng)的概括。
關(guān)鍵字: 礦田 推覆構(gòu)造 滑脫構(gòu)造 火山構(gòu)造
(Institute of Geology, Central South University of Technology, Changsha 410083)
Abstract:Focused on the basic structural characteristics of Laochang Ag-Pb orefield in Lanchang, Yunnan, in an all-round way, the folds, faults, nappe structures, decollement structures, basemental (fault) structures and volcanotectonics developed in the orefield have been approached. For the first time, a large-scale decollement structure in the studied region was found, and its characteristics, genesis and relation to the metallization were discussed in details, which, therefrom, clarifies the metallogenic structures of the ore filed that had been in suspense for a long time. Aimed at the three different types of orebody groups within the ore deposit, discussion was made from the angle of ore-controlling structures on the controlling effects of the different times, types and levels of structures on the orebodies. Furthermore, the volcano-tectonics in the region were interpreted and located accurately by remote sensing method. A new opinion was put forward that there was in Laochang district volcanodepression whose secondary craters controlled the Laochang Ag-Pb ore deposit. Finally, a summary on the relation between structures and metallization was systematically made on the basis of the sturctural evolution history.
Key words: orefield nappe structure decollement structure velcanotectonics


