Three Dimensional Geological Modeling And Analysis In The He Yuan Bei Ju Long An Aera Of The Xiangshan Uranium Ore Field

Xiangshan uranium ore field is one of the earliest exploration,research and exploitation of a group of volcanic rock type uranium deposits,the proved reserves in the exploitation of uranium resources and reserves occupy an important position.In order to looking for new uranium exploration target area and need of Xiangshan volcanic basin deep geological 3D structure feature of fine detection and analysis.To this end,Beijing Nuclear Industry Geological Research Institute to carry out the project of "basic geological research in Xiangshan area".(Belonging to the CNNC longchan project).The project to AMT detection as the main technical means,And combined with geological survey research,gravity and magnetic inversion,radioactivity survey,soil geochemistry and so on.Using 3D geological modeling technology,Integration of the related geological exploration-geophysical-geochemical data and comprehensive interpretation of the results,The establishment of Xiangshan area fine 3D geological structure model,The prospecting services for a new round of uranium deposits in Xiangshan area.This paper is one of the components of the project,The main river yuan back julong'an key exploration area,Using AMT to detect profile data,Combined with geologic mapping and a large number of exploration engineering data,Geological and geophysical integrated interpretation of the interface and fracture structure of the main geological units in this area;And based on the advanced GOCAD 3D geological software,Three dimensional geological model of important geological factors in this area is established,Three dimensional spatial structure analysis of geological factors,Prediction of new target areas for uranium exploration.1 Collecting and arranging the Yuan yuan bei ju long'an key exploration area of surface geological map,61 borehole data,47 AMT data,DEM data and sub meter resolution remote sensing image,Through a series of technical methods,These data will be integrated on the MAPGIS platform,Establishment of 47 geological geophysical integrated interpretation system in this area,In the system,Surface geology and deep exploration,AMT apparent resistivity profile information can be presented in a comprehensive,It has laid a foundation for the deep geological structure interpretation.2 According to the previous project on determination results of sample physical parameters of main geological units in Xiangshan area,Profile information observation analysis combined with the he yuan bei drilling ju long an area exposed geological point,To determine the area of ehuling group clastoporphyritic rhyolite high resistivity,Daguding group rhyodacite for low resistivity,The metamorphic basement of quartz schist is high resistivity,Phyllite is low resistivity The AMT profile in the study area is composed of upper and lower,The overall performance of the "high resistance-lowresistance-highresistance" Three layer structure of electrical characteristics.The unconformity between the k1 volcanic rock series and the basement metamorphic rock is the main body of the unconformity interface and the lowest resistivity.The resistivity of theK1e/K1 d interface between the groups is about1850?·m,Based on the above characteristics,the boundary,the unconformity boundary between the base and the fault structure of 47 geological geophysical integrated sections are completed.3 Three dimensional geological software based on GOCAD,The surface geology,drilling engineering,AMT profile of apparent resistivity measurement point data,DEM,remote sensing image and so on are integrated,Data interpolation method using reverse distance weighted method(IDW),The data body can be carried out in any direction of cutting and three-dimensional observation,calculation;Interpretation of the above geological and geophysical comprehensive profile,Through a series of space coordinate calculation and format conversion,Import GOCAD system,Three dimensional observation and adjustment of AMT apparent resistivity data volume in three dimensional space,Perfect the boundary of geological unit;Using Smooth discrete interpolation(DIS)method,Interpolation processing of the geological unit boundary,Constructing the model of the interface between the two groups,the unconformity interface and the fracture surface,And then the 3D geological entity model is constructed by using the model,the model of the bottom surface,the interface model,the base model and the model of the fault plane.4 Through the analysis of the He Yuan bei-julong'an interface and 3D geological entity model,get the following conclusion:1?In the He yuan bei-Ju long an aeras,the unconformity interface shows the South and North uplift and middle depression,Its direction for the EW-NNW,It is Characterization of volcanic collapse structure,The maximum height difference is1400m±,The deepest collapse Near the dan qian(1200±).2?In the volcanic collapse zone,There is a series of depressions in the basement unconformity,He yuan bei is the most,There are a Steep zone,in the chuan keng-zheng jia-shu tang area,The steep belt direction is approximately NE-SW,Height 200m±,The integral expression of the basement unconformity interface is the structural pattern of the sag uplift depression.3 ? There are a Similar collapse structure both group interface and Substrate unconformity interface,Only the depth of collapse is different,The most Height is1000m±,The deepest collapse Near the dan qian(800±),This show that group interface collapse structure is inheritance and development of unconformity interface.4?Mineralization is overall Near EW direction distribution,And distributed in group interface uplift zone or group interface Steep zone,composite control of structure and group interface uplift zone or structure group interface Steep zone,According to the theory of similar analogy,Believing group interface uplift zone of Northwest He yuan bei and chuan keng-zheng jia-shu tang steep zone is favorable metallogenic belt.