Abstract:The Gejiu tin deposit in Yunnan Province is controlled jointly by Middle-Late Yanshanian biotite granite, Middle Triassic strata of limestone intercalated with dolomite and a series of NE-and EW-trending fractures, folds and interstratal structures. The deposit is dominated by cassiterite-sulfide type ore with the association of various types of polymetallic ores. As the mining area has been intensively investigated and explored for ages, the search for new orebodies seems to be extremely difficult. Nevertheless, some new advances have been achieved recently by using different techniques. 1. An integrated ore prediction method was used by combining and contrastirig the statistical prediction of ore resources with the traditional geological analogy, and this led to the discovery of the bedded-veinlike type rich and thick tin-lead deposit 600-700 m below the surface at the Lutangba prediction area in the northeast of the mining district. 2. The Xinshan granite in the south of the mining district has mushroom-shaped tongue protrusion, and tin-copper orebodies are frequently concentrated at the concave position below the tongue. This resulted in the establishment of the below-tongue metallogenic model whose subsequent utilization helped to discover the large-size Shuangzhu concave type tin-copper deposit. 3. A deep investigatito into the material composition of the ore deposit led to the discovery of such new tin minerals as nordenskioldine, schoenfliesite and varlamoffite and, moreover, to the formulation of the presumption that stanniferous skarns dominated by such new tin minerals and scattered tin make up prospective tin ore deposits. 4. The further integrated ore prospecting was carried out. Gold anomaly was detected at the Kafang metadiabase with the help of geochemical prospecting, and an associated gold deposit of a certain dimension was disclosed at the Jinguangpo metadiabase copper-tungsten-bismutb polymetallic deposit in the same area. 5. A study of typomorphic peculiarities of cassiterite reveals the existence of three types of cassiterite belonging to three different metallogenic stages. The investigation indicates that cassiterite from a relatively large tin deposit, in the west of the mining district is mainly product of pneumato-hydrothermal stage, quite similar to cassiterite contained in the nearby granite porphyry and its alteration-mineralization zone. It is therefore tentatively considered that a kind of porphyry tin deposit exists in this area.
文章编号：
中图分类号：
文献标志码：
引用文本：
彭程电.1986.略论个旧锡矿床地质找矿的新发现及其途径[J].矿床地质,5(3):37~48.1986.New Discoveries In Geological Prospecting Work Of The Gejiu Tin District'and The Technioues Employed[J].Mineral Deposits5(3):37~48
图/表
