湖南锡矿山锑矿区北矿首次发现Ⅳ号锑矿体

First discovery of No.Ⅳantimony ore body in the northern mine of a tin mine,Hunan Province

2021—2022年,湖南锡矿山锑矿区北矿的接续资源勘查工作取得重大突破,首次在北矿的老矿山矿床和童家院矿床发现了Ⅳ号锑矿体,均为层间破碎带中的锑矿体。经分析,在老矿山矿床实施的钻孔ZK3001见2层Ⅳ号锑矿体:第1层Sb平均品位为4.23%,真厚度为3.30 m;第2层Sb平均品位为1.30%,真厚度为2.00 m。在童家院矿床实施的钻孔KZK01401见1层Ⅳ号锑矿体,Sb品位为3.96%,真厚度为1.03 m。研究表明,Ⅳ号锑矿体受断裂构造和地层联合控制,矿体产于NE向F_(72)和F_(3)断裂下盘的棋梓桥组硅化灰岩和层间破碎带中,单个矿体以透镜状、侧羽状、扁豆状产出,具尖灭再现特征。断裂下盘的矿体走向NE-SW,倾向NW,倾角60°左右;层间破碎带中的矿体走向NE-SW,倾向SE,倾角20°左右。龙口冲砂、页岩段及棋梓桥组中的薄层页岩是Ⅳ号矿体富集的有利屏障,具有“断裂构造+有利岩性+屏蔽层”的控矿特征。在锡矿山北矿首次发现的Ⅳ号锑矿体能够直接开发利用,既能延长矿山的服务年限,又对研究锡矿山深部构造与矿体的关系具有重要意义。将棋梓桥组划为锡矿山的第二成矿空间,为该区下一步接续资源勘查找矿明确了方向,具扩大锡矿山北矿(锑矿)矿产资源的前景。

From 2021 to 2022,a major breakthrough has been made in the exploration of successive resources of the northern mine in the antimony deposit of a tin mine,Hunan Province.For the first time,the antimony body No.Ⅳwas discovered in the Laokuangshan and the Tongjiayuan deposits of the northern mine,both of which are antimony ore bodies in the interlayer fracture zone.There are two layers of No.Ⅳantimony ore body in borehole ZK3001 of the Laokuangshan deposit.The average grade and true thickness of the first layer of No.Ⅳantimony ore body are 4.23%and 3.30 m,while those of the second are 1.30%and 2.00 m.There is one layer of No.Ⅳantimony ore body in borehole KZK01401 of the Tongjiayuan deposit,whose grade and true thickness are 3.96%and 1.03 m,respectively.No.Ⅳantimony ore body is controlled by faults and strata,and occurred in the silicified limestone of the Qiziqiao Formation and interlayer fracture zones in the foot wall of NE-trending faults F_(72) and F_(3).Individual ore body is formed in lenticular,lateral pinnate or lentil shapes with pinching-out recurrence.The fault footwall ore body strikes NE-SW and dips NW at about 60°,while the ore body in the interlayer fracture zone strikes NE-SW and dips SE at about 20°.Sandstone and shale section of Longkouchong,and thin shale of Qiziqiao Formation are favorable barriers for enrichment of No.Ⅳorebody,with ore-controlling characteristics of fault structure,favorable lithology and shield layer.The first discovery of No.Ⅳantimony ore body in the northern mine of the tin mine can be directly developed,which can not only extend the service life of the mine,but also have great significance for the study of the relationship between the deep structure of the tin mine and the ore body.The Qiziqiao Formation is seen as the second metallogenic space of the tin mine,which makes clear the direction for further resource exploration and prospecting in this area,and is expected to expand the prospect of the northern mine(antimony ore)of the tin mine.