云南来利山锡矿锡石标型特征及其找矿意义

The study on the typomorphic characteristics of cassiterite of Lailishan tin deposit in Yunnan province and its prospecting significance

来利山锡矿位于三江成矿构造带南端,是滇西地区著名的锡多金属矿床之一.应用成因矿物学与找矿矿物学的理论和方法,对该矿主要矿石矿物锡石进行了标型特征研究.结果表明:自成矿早期至成矿晚期,锡石的结晶习性由锥面发育向柱面发育演化,锡石热电导型由P-N型向N-P型逐渐过渡.锡石阴极发光条件下显示出的环带构造可能与U,Th等元素含量有关.其中,淘金处矿段锡石与老熊窝矿段、三个硐矿段锡石的晶形、大小、长宽比等有明显不同,淘金处矿段锡石环带最为发育,且热电性以P-N型为主.综合认为淘金处矿段成矿温度高于老熊窝和三个硐矿段,抑或淘金处矿段即是该矿区成矿热液活动中心.因此淘金处最具找矿潜力.这个研究成果为探讨成矿物质和热液来源及进一步找矿勘查提供了科学依据.

Lailishan tin deposits is one of the well-known tin polymetallic deposits in western Yunnan,located at the southern of Sanjiang metallogenic structural belt.In this paper,the typomorphic characteristics of cassiterite,the main ore mineral of the deposit,have been studied by applying the theories and methods of genetic mineralogy and prospecting mineralogy.The result shows that from the early mineralization to the late mineralization,the crystallization habit of cassiterite transforms from conical development to the cylindrical developmental,the thermoelectricity type of cassiterite transforms from P-N type to N-P type.The ring zone of cassiterite in the cathodoluminescence may be related to the content of U,Th and other elements.The ore block of Taojinchu has a obvious difference with Laoxiongwo and Sangedong in crystalline form,size,length-width ratio of cassiterite,and also the ring zone of cassiterite is best developed in the ore block of Taojinchu,the thermoelectricity of cassiterite mainly shows P-N type.It is generally considered that the metallogenic temperature of the ore block of Taojinchu is higher than that of LaoXiongwo and Sangedong,or that the ore block of Taojinchu is the metallogenic hydrothermal activity center of the mining area.Therefore,the ore block of Taojinchu has the most prospecting potential.The research results provide a scientific basis for further prospecting and exploration of ore-forming materials and hydrothermal sources.