基于构造地球化学异常的金矿床蚀变带深部推断三维建模——以山东夏甸金矿为例  

3D inferred modelling on deep alteration zone of gold deposits based on tectonic geochemical anomalies: A case study of the Xiadian gold mine in Shandong Province

作　　者：陈进[1,2] 毛先成[1,2] 杨斌[1,2] 邓浩[1,2] Chen Jin;Mao Xiancheng;Yang Bin;Deng Hao(Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring,Ministry ofEducation,Changsha 410083,Hunan,China;School of Geosciences and Info-Physics,Central SouthUniversity,Changsha 410083,Hunan,China)

机构地区：[1]有色金属成矿预测与地质环境监测教育部重点实验室(中南大学),湖南长沙410083 [2]中南大学地球科学与信息物理学院,湖南长沙410083

出　　处：《地质学刊》2018年第3期379-385,共7页Journal of Geology

基　　金：国家自然科学基金项目"基于重磁电正反演的隐伏矿体三维预测模型修正方法研究"(41472301);"面向隐伏矿体三维预测的成矿空间复原方法研究"(41772349);山东省重点研发计划项目"招平断裂带中段深部金矿成矿理论;找矿方法与成矿预测"(2017CXGC1605);国家重点研发计划项目"深部成矿构造三维分析与建模预测"(2017YFC0601503)

摘　　要：随着三维地质建模技术的发展,构建能定量表达地质体特征的可视化三维模型已成为重要的研究方向。已有地质钻探资料难以对研究区深部全面覆盖,因此难以定量描述蚀变带的深部特征,也无法获得蚀变带三维建模的关键形态参数。针对该问题,提出了一种通过地表的构造地球化学异常来推断蚀变带三维建模的关键形态参数——蚀变带中心深度和厚度的方法,并设计一种蚀变强度定量表达和蚀变带内部结构模拟算法来实现蚀变带内部结构的定量化表达。该方法在同等化探异常级别的条件下,以化探与钻探重叠区蚀变带中心深度和厚度构建蚀变带深度-厚度的映射模型,进而提供参数来构建蚀变带三维形态模型,并基于此模型实现蚀变带内部"强蚀变单元"和"非强蚀变单元"的分布模拟,最后获取蚀变带内部所有单元的定量化蚀变强度。将该方法应用于山东夏甸金矿,证明构造地球化学异常能够为金矿蚀变带深部推断三维建模提供数据支持。With the development of 3D geological modelling technology, it has become an important research area to construct a visual3D model capable of quantitatively expressing features of geological bodies. It is hard to fully cover the depth of the study area with presentdrilling data, making it difficult to quantitatively describe the features of the deep alteration zone, and the key morphological parametersfor 3D modelling of the alteration zone cannot be obtained. Thus, the paper proposes a method to infer the key morphological parameters ofthe 3D modelling of the alteration zone （i.e., the central depth and the thickness of the alteration zone） according to the tectonic geo？chemical anomalies on the surface, and designs a quantitative expression of the alteration intensity and a simulation algorithm on internalstructure of the alteration zone to quantify the internal structure of the alteration zone. The method is to statistically establish the depth-thickness mapping model by the central depth and the thickness of the alteration zone located at the overlapping area of geochemical explo？ration and drilling under the same geochemical anomaly grade. Parameters could be derived from the mapping model to construct a 3Dmorphological model and simulate the distribution of ″strong alteration units″ and ″non-strong alteration units″. Finally, the paper obtainedthe quantitative alteration intensity of all units within the alteration zone. The method was applied to prove that tectonic geochemical anomalies in the Xiadian gold deposit can provide data support for the 3D inferred modelling on the deep alteration zone of gold deposits.

关 键 词：地质三维建模 围岩蚀变强度 构造地球化学异常 山东夏甸金矿 

分 类 号：P618.51[天文地球—矿床学] TP391.41[天文地球—地质学]