Abstract:An investigation into geologic settings, metallogenic processes, source materials and mineral assemblage of some typical wollastonite deposits in China has led the authors to group them into three genetic types: 1. Stratabound contact-metamorphic deposits. Stratiform, stratoid and lenticular ore bodies of this type have been formed in the contact zone between intrusive and siliceous limestone as a result of contact-metamorphism An examination and comparison of the contents of minor elements in wollastonite, relict siliceous mass in ore-bearing bed and quartz in granite suggest the probable derivation of SiO2 from siliceous material in limestone. Mineralization seems to have been governed by sedimentary formation of the host rock. Associated minerals are chiefly calcite, quartz. etc. Ore is extremely pure in quality and high in grade. The Changweizi deposit in Jilin Province serves to be an example of this type. 2. Skarn-type deposits. This type of wollastonite deposits has been formed through matasomatism at the contact zone between limestone and intrusive body. Lenticular in shape, the ore bodies are frequently noticed associated spatiajly with skarn type copper ores. SiO2 was probably chiefly introduced from the intrusive. Garnet, diopside, etc. make up the major associated minerals. Elevated contents of sulfides are observed somewhere in the ore bodies. This type of deposits might be well examplified by the Xiaojipu deposit in Hubei Province. 3. Wollastonite deposits related genetically to regional metamorphism. No commercial deposits of this type have so far been found in China. The abundant silica contained in the limestone must have been a most favorable condition for the formation of ore deposits-whatever type they might belong to geologic terrains adjacent to the contact zone between siliceous limestone and intrusive body or subjected to regional metamorphism are most prespective areas in search for wollastomte deposits.
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曲元贵, 刘志贤, 孙鸣飞.1983.我国硅灰石矿床成因类型及地质特征[J].矿床地质,2(4):89~.1983.Genetic Types And Geologic Settings Of Wollastonite Deposits In China[J].Mineral Deposits2(4):89~
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