The Three-dimensional Modeling And Tectono-metallogenic Dynamics Of Tongshan Copper Deposit, Anhui Province

Tongshan copper deposit, located at the Guichi, Anhui province, is a skarn deposit. Previous research focused on the geochemistry characteristic of ore-related intrusion and the deposit. In this paper, research focus is on it's structures. By the comprehensive analysis of all existing geo-data, three-dimensional geological modeling and structural geology surveying, the regularity of structural controlling on ore-bodies and its dynamic mechanism are analyzed, based on systematic summary of geological and geochemical characteristics of the deposit. Major accomplishments achieved in this thesis include 5 aspects as following.1) The 3D modeling of ore bodies and the related geo-factors are first accomplished, that is a new method for demonstrating spatial relationship of all geological factors and analyzing the regularity structural controlling on ore bodies.2) By analyzing the spatial distribution of Cu grade in ore-bodies, it is demonstrated that, for the ore-bodies of No.29 and No.30, the high grades are scattered in the upper but become more concentrated down under; for the 4^th ore body, the high grades are concentrated in the most crooked segment rather that the flat segment of the contact zone. This distinction distribution of Cu in ore bodies may be related to the mode variation of ore-controlling faults.3) By comprehensive investigation and analysis on the ore field structural geology, control of thrust-fold system on ore-related intrusion is demonstrated, and a hidden intrusion probably related to Cu mineralization is predicted.4) An oblique-slip duplex fault system is discovered and its controls on ore bodies is demonstrated, which can be used as basis for predicting ore bodies.5) By statistical analysis on the occurrence mode of the fault and fractures, it is found that early structure might have a successive influence on the late structures, resulting in complix of the structural characteristics.