Research On 3D Prospectivity Prediction Of Buried Orebodies In Yangzhuang Iron Ore Deposit Based On Characteristic Analysis Method

With the surface, recognizable and shallow ore deposits reducing day by day, the ore-finding is becoming more difficult and the effect of ore-finding is increasingly lower. The mineral exploration has been facing "three difficulties" problems, more and more mine is "difficult to identify, difficult to find and hard to exploit". The 3D metallogenic prospectivity mapping is proposed to provide solutions and new ideas for the current difficult ore-finding situation.Through the comprehensive research and secondary development on geological prospecting data, guided by the metallogenic regularity of YangZhuang deposit, this paper assimilates three dimension geological modeling,3D metallogenic prospectivity mapping, the method of characteristic analysis, etc, studies and implements drilling geological database, geological solid models and block models, the spatial analysis of geological ore-controlling factors, the model of characteristic analysis on YangZhuang iron ore deposit and based on the results of all these steps, delineate out the prospecting target areas of YangZhuang deposit.The main content of this paper includes the following several aspects:(1)After collecting and analyzing the geological exploration data of YangZhuang iron ore deposit, the drilling geological database is established by Access and Surpac software.(2)Based on the drilling geological database and geologic section, this paper has built the 3D solids models of orebodies, stratums, rocks in Yangzhuang deposit.(3)In three dimensional space, several prospecting information has been extracted by using 3D spatial analysis, such as 3D buffer analysis, analysis of 3D uplift depression degree, extraction of concave convex of geological body etc, and identified 12 predictors.(4)According to the theory of characteristic analysis method, using the programming language C# to realize the software module of 3D characteristic analysis method.(5)Under the guidance of the metallogenic regularity of Yangzhuang iron ore deposit, the software module of 3D characteristic analysis method is used to calculate the weight of prediction variables, and then calculate the connection degree of all prediction units in the study area.(6)Based on metallogenic possibility, the paper delineates 3D metallogenic prospective areas in the deep and marginal areas of Yangzhuang iron ore deposit.The research of three dimensional prospectivity mapping in the deep and marginal areas of Yangzhuang iron ore deposit is helpful to enlarge the resource reserves of the areas and important to guide the prospecting in the depth and border of known deposits.Through the above research work, it is reached the following conclusions:(1)The three dimensional geological models which has created for this study can reproduct the space form of the orebodies, stratum, rocks of Yangzhuang iron ore deposit in three dimensional space and can provide data and support for spatial analysis and prospectivity mapping.(2) The algorithm of 3D characteristic analysis method which has realized for this study is consistent with the fundamental principles of characteristic analysis method, and can calculate the weight of prediction variables and the connection-degree of all prediction units in Three-dimensional space.(3)The method of characteristic analysis is carried out in two dimensional space for prospectivity mapping in the past and this paper extends this method to three dimensional space for forecasting YangZhuang iron ore deposits, showing the effect of 3D metallogenic prospectivity mapping is good and can predict the possible position, depth and form of unknown orebodies in the deep and marginal areas of known orebodies.(4)This research delineates ten prospecting targets.3 first level prospecting targets,3 second level prospecting targets and 4 third level prospecting targets are delineated for finding iron ore deposit. The first level prospecting targets locate in the northeast of the known orebodies and its nearby, its metallogenic conditions are terribly favorable. The second level prospecting targets locate in the north of the known orebodies and its nearby, its metallogenic conditions are favorable. The third level prospecting targets locate in the east and west of the known orebodies and it has certain metallogenic conditions.