中文摘要:矿区内存在纬向和反“S”型两类构造体系,后者的控岩控矿作用十分明显。含矿裂隙以北北西至北西向右行压扭性断裂破碎带为主,层间破碎带为次之。控矿构造主要有斜列式和层间破碎带两类。矿化类型为锡石电气石石英脉型。据花岗岩的含矿性及其与矿化的紧密关系,以及氧、硫同位素、包体测温、热晕和蒸发晕特点等资料综合分析,该矿床是在多期次构造活动控制下,矿物质主要来自岩浆源的气化一高温热液复式矿床,主要是受反“S”型构造体系的控制。
Abstract:The Haobadi tin orefield is located on the southeastern side of the cormpounding part between the Lancangiiang fault zone of Qinghai-Xizang reversed “S”-shaped tectonic system and the Baoshan-Zhengkang anticlinorium structural belt of western Yunnan meridional structural systern, and also lies along the westward extension portion of the western section of Nanling latitudinal tectonic belt. The magmatic rocks related to metallization are Late Yanshanian biotite granites with Rb-Sr biotite age and K-Ar age being 64.7 Ma and 64.6 Ma respectively. Exploration demonstrates that several small rock bodies are connected with each other at depth, conditioned stricly in time and space by NNW-trending fault zone of the reversed “S” - shaped structural belt. The structures in this area can be grouped into latitudinal and reversed “S”-shaped structural systerns. The latitudinal structural features are NE-trending anticlines and longitudinal extensional faults, which bear compresso-shearing characteristics as a result of superimposed transformation of the reversed “S”-shaped structures and fail to play an obvious ore-controlling role. The reversed “S”-shaped structural zones, on the contrary, are dominant in the ore district and show apparent ore-controlling function, with the NNW-trending cornpresso-shearing fractural zones governing the approximately parallel distribution of three tin metallogenic zones. The ore-bearing faults are mainly NNW-NW dextral compresso-shearing fractural zones several hundred meters in length and tens of meters in width, which incline steeply in NE or SW direction and strictly control the distribution of orebodies and ore zones, the interformational fractural zones possess the secondary importance, which control most stratoid oredodies and belong chiefly to derivative components of the NNW-trending compresso-shearing faults and partly to lower order structures of latitudinal structural belt. The multistage mineralizations in the ore district are closely related to polyphase activities of reversed “S”-shaped structural zones; the orebodies are mostly in inclined arrangement, and each ore zone consists mainly of complex ore veins, which even reach 2-4 layers; the second order single ore veins are crowded, assuming imbricate arrangement.
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李光勋.1988.滇西薅坝地锡矿的矿田构造分析[J].矿床地质,7(4):65~72.1988.Structural analysis of the Haobadi tin orefield in western Yunnan[J].Mineral Deposits7(4):65~72
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