The Study On Tectonic Deformation And Its Ore-controlling Features In Daping Gold Deposit Yuanyang Yunnan Province

Daping gold deposit is regarded as the most typical gold deposit in the southern part of the Ailaoshan orogenic belt,the ore body is strictly controlled by metallogenic fracture's structure.The tectonic activity is frequent and strong in this area,with the characteristics of multi-period,long-term and inheritance.The structure not only controls the distribution of the strata,the emplacement of the rock mass in this area,but also it has a strict control to the distribution of the ore body,making it become the dominant factor in ore control.The ore-forming of this deposit is mainly controlled by NNW Xiaozhai-Jinping fault,NNW Xiaoxinjie fault and NW Sanjiahe fault which are from east to west.To Xiaoxinjie fault for the boundaries,east of the ore is divided into the west mineralization zone,the main object of the study is NW V1-2-3 veins;West of the ore is divided into the west mineralization zone,the main object of the study is NNW V9-8-14 veins.In order to study the tectonic kinematic characteristics,ore-controlling laws and metamorphic deformation effects,the ore body morphology,veins' attitude,morphological and spatial distribution of tectonic lens and fault breccias,steps and scratches are observed and researched in this paper,also,the EBSD composition analysis was performed on the quartz in the ductile shear zone,and achieved the following achievements and awareness:(1)Morphological studies of the two veins indicate that they are like beaded and pods in the plane,meanwhile,their distribution type is geometrical and equidistant in the profile,side direction is to the south east.The expansion of the fracture site is a favorable location for mineralization enrichment,constituting a thick gold ore body,the intermittent distribution of multiple pod-like gold bodies constitutes Daping gold mine.The lateral direction of the gold deposit coincides with the oblique depth extension of the vein.In space,segmentation enrichment,local concentration,distribution spacing is similar,these are to the formation of mineralization enrichment and mineralization enrichment zone.The thickness center of the ore body is consistent with the concentration center of the ore body.The extension of the vein indicates that the direction of migration of ore-forming fluids is from south-east to north-west,mineralization enrichment has a certain side of the law,that is from the north-west to the deep side volts of south-east direction.(2)Based on the morphological and spatial distribution of the structure lens and the faulted breccia,the joint analysis of the step and scratches,it is judged that the ore fault is the left row shear normal fault.(3)The analysis of quartz EBSD structure of ductile shear zone shows that the deformation temperature of quartz is low temperature(<400?),which reflects this earea experienced a low temperature deformation metamorphism.(4)The pole shot red flat projection of veins and fault attitude shows that the veins are formed in the left-handed torsional fracture.In this paper,the characteristics of ore-controlling structure and the laws of ore body enrichment are discussed in detail,which is of great significance to deep metallogenic prediction and prospecting.