摘 要 蚀变围岩作为斑岩钼矿矿床的重要特征之一，备受学者们重视。蚀变围岩的物理化学条件和热液性质为推断矿床的演化、成矿元素的迁移、富集、矿石沉淀及丰富成矿理论提供了有力的证据。同时，蚀变岩也可以作为重要的找矿标志。 论文以陕西省柞水县杨木沟钼矿床为研究对象，在矿区地质资料收集、野外地质调查与矿石系统采样的基础上，室内借助反光显微镜鉴定、电子探针分析和岩石地球化学测试等现代地质学分析手段，获得了围岩蚀变矿物化学成分、主量元素地球化学、微量元素地球化学等数据，确定了矿床蚀变类型及蚀变分带，查明各期蚀变事件的产出环境及所引起的矿化现象，总结了找矿标志，并分析了矿床的成因。 研究结果认为：杨木沟斑岩钼矿床围岩蚀变类型主要为硅化、钾长石化、黑云母化、绢英岩化、绿泥石化、泥化及青磐岩化。其中辉钼矿化与硅化、钾长石化关系最为密切。矿化现象明显受到地质构造的控制，矿体主要集中于f1与f2构造蚀变带之间和其临近的上下盘附近，并与构造带产状一致。蚀变矿物中Si、K含量很高，说明Mo的富集异常跟石英脉密切相关。在热液入侵过程中有Cu、Zn、Ni、Co、V、Nb、Sc、Ba等元素的带出，有Pb、Ag、Hf、Zr等元素的带入，说明围岩蚀变在不同温度环境都有发生。在δEu－Sr图中发现，矿区引起围岩蚀变的热流体主要来自于壳源，但也受到幔源的微弱影响。地表的负地形、石英脉、褐铁矿矿化带可作为直接的找矿标志。

ABSTRACT Altered rocks was brought to the attention of the scholars, as is one of the important characteristics of porphyry molybdenum deposits. The physicochemical condition and the hydrothermal fuild of altered rock has important significance in both reasoning the evolution of deoposit and their migration、enrichment、deposition of mineralization elements, and enriching ore forming theory. Meanwhile, altered rocks can be used as one of the important prospecting marks. The this paper takes the YangMuGou-molybdenum deoposit in ZhaShui county Shaanxi province as the research object. Based on the the article study regional geology and mining area geology and collect samples, studies have shown the alteration types and zoning of the YangMuGou-molybdenum deoposit, the environment and mineralization of alteration process on the basis of the data, which is from modern geology analysis method of reflecting microscope、electron probe、rock geochemistry, from what altered minerals and trace element and major element geochemical to prospecting criteria and ore genesis . Studies have shown that the wallrock’s alteration types of the YangMuGou-Mo deoposit mostly comprise silification、K-feldsparizatio、biotitization、serictization、chloritization、 Mudding and propylitization, in which Mo-mineralization closely associated with silification、K-feldsparizatio. Mineralization controlled by the structure significantly, the orebody mainly has concentrated upper and footwall between tectonic alteration zone of f1 and f2, and was in accordance with the occurrence of tectonic belt. The high Si、K of altered minerals show enrichment of Mo are closely related quartz vein. It shows alteration of wall rock in different temperature environment in the process of the hydrothermal intrusion, which out of Cu、Zn、Ni、Co、V、Nb、Sc、Ba and into of Pb、Ag、Hf、Zr etc. In the diagram of δEu-Sr, thermal fluid of causing the wall rock alteration mainly comes from the crust and seldom comes from the mantle. Negative landform、quartz vein、mineralization zone of the limonite can be used as direct prospecting criteria on the ground.