(1. 昆明理工大學(xué) 國土資源工程學(xué)院,昆明 650093;
2. 中國科學(xué)院地球化學(xué)研究所 礦床地球化學(xué)國家重點(diǎn)實(shí)驗(yàn)室,貴陽 550002;
3. 中國有色金屬工業(yè)昆明勘察設(shè)計(jì)研究院有限公司,昆明 650051;
4. 云南迪慶礦業(yè)開發(fā)有限責(zé)任公司,香格里拉 674400)
摘 要: 羊拉銅礦床是我國西南“三江”多金屬成礦域內(nèi)矽卡巖-斑巖型礦床的典型代表,為滇西北金沙江縫合帶中生代構(gòu)造-巖漿-成礦事件的產(chǎn)物。該礦床構(gòu)造發(fā)育,形成了一套褶皺-斷層控巖控礦體系。本文運(yùn)用礦田地質(zhì)力學(xué)方法對(duì)羊拉銅礦床構(gòu)造形跡的幾何學(xué)、運(yùn)動(dòng)學(xué)和力學(xué)性質(zhì)進(jìn)行解析,建立羊拉銅礦床的構(gòu)造體系及其控巖控礦模式。結(jié)果表明:自海西期→印支期→燕山期→喜馬拉雅期,羊拉銅礦床主壓應(yīng)力經(jīng)歷了東西向→北西向→北西向→(北東向→近東西向)的轉(zhuǎn)變,依次形成了早南北構(gòu)造帶、北東構(gòu)造帶(早-晚)、(北西構(gòu)造帶和晚南北構(gòu)造帶)。早南北構(gòu)造帶為羊拉銅礦床控巖控礦構(gòu)造的基礎(chǔ),早北東構(gòu)造帶為控制矽卡巖-斑巖成礦系統(tǒng)的主導(dǎo)構(gòu)造,晚北東構(gòu)造帶、北西構(gòu)造帶和晚南北構(gòu)造帶為破巖破礦構(gòu)造。根據(jù)構(gòu)造體系及其控巖控礦作用,認(rèn)為羊拉銅礦床構(gòu)造控巖控礦模式為海西期“層間斷裂”+印支期“侵入接觸構(gòu)造”+燕山期“λ字型構(gòu)造”+喜馬拉雅期“階梯狀構(gòu)造”。
關(guān)鍵字: 構(gòu)造體系;控巖控礦構(gòu)造;構(gòu)造控礦模式;羊拉銅礦床;滇西北
(1. Faculty of Land and Resource Engineering, Kunming University of Science and Technology, Kunming 650093, China;
2. State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China;
3. Kunming Prospecting Design Institute of China Nonferrous Metals Industry Co., Ltd., Kunming 650051, China;
4. Yunnan Diqin Mining Industry Group, Shangrila 674400, China)
Abstract:The Yangla Cu deposit is located in northwest Yunnan, China and formed during the Mesozoic structure-magma-mineralization events, is one of the typical skarn-porphyry deposits in the Jinshajiang suture zone, “Sanjiang” polymetallic metallogenic domain. Well developed structures in the Yangla Cu deposit composed a typical folds-faults rock- and ore-controlling structural system, which constituted the skarn-porphyry metallogenic system. In this paper, the theory and method of ore-field geomechanics are used to analyze the geometry, kinematics and mechanical property of the structure traces in the Yangla Cu deposit, and to determine the ore-field structural system and its mechanism of rock-and ore-controlling model. The results show that the Yangla Cu deposit mainly experienced transformation of main constructional compressive stress from EW- to NW- to NW- to (NE- to nearly EW) trending, and formed the early NS, NE (early to late), NW, late NS structure belts in turn, since the Hercynian→Indochina→Yanshanian→Himalaya, and affected the Jianshajiang suture zone and Indian-Eurasian plates. It is believed that the early NS structure belt was the rock- and ore-controlling structural framework system in the Hercynian. The early NE structure belt was provided a favorable structural setting for the skarn-porphyry metallogenic system, which was the dominant ore-controlling structural system in the Indochina. In contrast, the late NE structure belt destroyed the rock and ore-bodies, which belong to rock- and ore-breaking structure in Yanshanian. The NW and late NS structure belts also destroyed the intrusions and ore-bodies, and belong to the rock- and ore-breaking structure in Himalaya. The corresponding structure rock- and ore-controlling model are successively the “Interlayer Faults” of the Hercynian, “Intrusion into Contact Faults” of the Indochina, “λ-Type Faults” of the Yanshanian, and “Stair-Step Faults” of the Himalaya, which based on the structural system and its rock- and ore-controlling structure type.
Key words: structural system; rock- and ore-controlling structure; ore-controlling structure model; Yangla Cu deposit; Northwest Yunnan


