摘要
本文从矿床地质特征出发,以矿床的矿石类型为基础,考虑成因,强调矿床的工业意义,将滇东南锡矿带的矿床类型划分为两类、四组合、十四型。锡矿床围绕花岗岩突呈现规律性的空间组合,同时以成矿地质条件的差异、成矿作用的多样性,形成矿床类型的不同组合形式。
Along the Southeasten Yunnan tin ore belt genetically related to Yanshanian tectonic-magmatic cycle, tin is closely associated with such elements as tungsten, beryllium, bismuth, molybdenum, copper, lead, zinc and silver in time and space. With the granite as the center, the pneumato-hypothermal to mesothermal-epithermal mineralizations make up tin-polymetallic ore deposits dominated by cassiterite-sulfide type and cassiterite-quartz type ones which have been turned into placer tin deposits through denudation.The author has done his best to enable the classification of the ore deposits to reflect metallogenic factors, mineralization features and indicator characteristics which are readily recognized. Therefore, the classification of ore deposit types starts from geological setting of these ore deposits and bases itself on ore types (associations of ore deposits); in addition, it takes into account their geneses and lays emphasis on their economic significance.In this paper, a three-grade division system of class-association-type is adopted with genesis-indicator mineral association—ore-hosting geological body as the basis. The'class'of ore deposits is determined by genesis-econcmic significance, the 'association' (corresponding to subtype) by indicator minerals which show both genetic significance and specific metallogenic environment, and the 'type' by indicator ore-hosting geological system where a typical mineral association occurs. On the basis of these principles, the ore deposits along the Southeastern Yunnan tin ore belt are grouped into two classes,, four associations and fourteen types. Different types of tin deposits occur in regular association. The primary tin ore deposits show regular 'storeyed' three-dimensional mineralization association. The general tendency is like this:from the granite body outwards, there appear cassiterite-feldspar association→cassiterite-quartz association→cassiteritc sulfide association, typical metallogenic elements of Sn-W-Be-Mo-Nb-Ta-TR→Sn-W-Cu-In-Sn-Pb-Zn-As-Cd, and pneumato-hypothermal→hypothermal-mesotherrnal→mesothermal-epithermal ore deposits. The difference in metallogenic-geological environment (rock-forming and ore-forming effects of granite,host rocks and ore-hosting structural system)has led to the formation of different associations.
出处
《矿床地质》
CAS
CSCD
北大核心
1990年第1期35-48,共14页
Mineral Deposits
