投稿时间：2013-04-19
修订日期：2013-07-05
网络发布日期：2013-12-29
中文摘要:四川省白玉县呷村银多金属矿床是中国著名的VHMS矿床之一，前人曾进行过详细的矿床模型研究。对于矿床下部脉状矿体大致呈层状平行于上部块状矿体的地质现象，前人曾提出“层状矿席+层控网脉状矿带”等模式。文章通过对呷村矿床地质特征的详细研究后认为，呷村矿床在印支期形成之后，遭受到燕山期弧-陆碰撞造山的强烈改造，导致矿区地层直立并倒转，并在能干性弱的流纹质火山岩中普遍发生层内韧性剪切变形，使原先近于垂直层状矿体和喷气沉积岩的下-中部脉状-网脉状矿体被构造置换为紧闭褶皱状、无根褶皱状、透镜体状，并近于平行于上部层状矿体。构造恢复表明，下-中部脉状-网脉状矿体原始三维形态为不整合的筒状或漏斗状，与上部层状矿体组成典型的“下筒上层”的“双层结构”。根据脉状-网脉状矿体和层状矿体的空间展布特征，在构造恢复的基础上重新建立了呷村VHMS矿床的双通道夹卤水池的矿床模型。该模型对矿区外围找矿有一定的指导意义。
Abstract:The Gacun silver polymetallic deposit in Baiyu County of Sichuan Province is one of the most famous VHMS deposit in China, and previous researchers had conducted detailed studies of the deposit model. In order to explain the geological phenomenon that the lower vein ore body is roughly stratified and parallel to the upper massive ore body, the previous researchers proposed the model of "sheeted ore zone + stratabound stockwork ore zone"; nevertheless, the concept remains confusing and doubtful. The authors hold that, after the formation of the Gacun deposit in the Indosinian period, the deposit suffered strong Yanshanian reformation at the collision stage between the arc and the continent, which resulted in the uprightness and overturning of the strata in the deposit, and the rhyolitic volcanic rocks with weak competence were generally subjected to the intraformational ductile shear deformation. As a result, the lower and middle vein and the stockwork ore body which were originally vertical bedded ore body and exhalative sedimentary rock were transformed into tight fold, rootless fold lenticular in form and parallel to the upper bedded ore body. Structure restoration shows that the original 3D shape of the lower and middle vein and stockwork ore body was unconformably tubular or funnel-shaped, and combined with upper bedded ore body to form typical "lower tubular and upper stratiform structure" named "bilayer structure". On the basis of spatial distribution characteristics of the vein and stockwork ore body and the bedded ore body, and according to structure restoration, the authors reconstructed the two-channel clip brine pool deposit model of the Gacun VHMS deposit. The model has certain guiding significance for the prospecting work in the periphery of the ore deposit.
keywords:geology ductile shear deformation structural transposition VHMS deposit model Gacun silver polymetallic deposit
文章编号：
中图分类号：P618.52
文献标志码：
基金项目:本文得到西部矿业股份有限公司科研项目资助
引用文本：
党院,陈懋弘,毛景文,薛志强,李义邦,辛天贵,王康,高扬,吴学龙.2013.基于构造解析重建的四川呷村银多金属矿床模型[J].矿床地质,32(6):1077~1092DANG Yuan,CHEN MaoHong,MAO JingWen,XUE ZhiQiang,LI YiBang,XIN TianGui,WANG Kang,GAO Yang,WU XueLong.2013.Deposit model reconstruction of Gacun silver polymetallic deposit in Sichuan Province：Based on tectonic analysis[J].Mineral Deposits32(6):1077~1092
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