Geological Characteristics And Deep Metallogenic Prognosis Of Qidashan Iron Deposit Within Anshan,Liaoning Province

Qidashan Iron Ore Deposit is geotectonicaly located in the western part of the Liaoyang-Benxi Depression(level IV)of the Taizihe-hunjiang Depression(level III)of the Jiaoliao Uplift(level II)of North China Paraplatform(level I),and is a typical ore deposit in the exploration area of Anshan-Benxi Iron Ore Deposit with the genetic type of sedimentary-metamorphism.Within the mining area,the industrial ore body mainly occurred in metamorphic sequence of the Yingtaoyuan Formation(F.m.)in the Anshan Group,appear to be stratiform-like and stratiform shapes,move toward the northwest,tending to the southwest or northeast,and the dip angle is greater than 70 degrees,and are conjunctively controlled by Yingtaoyuan F.m.,Qidashan granite,and east-west trend tectosome.Qidashan iron ore deposit is mainly poor iron ore.The average TFe grade of the ore deposit is 30.42%.The iron ore-rich ore is a magnetite-rich ore,with scattered distribution.The main metal minerals in the ore are magnetite.The minor metal minerals are pseudomorphous hematite,siderite,pyrite and trace chalcopyrite;the non-metallic minerals are mainly quartz,tremolite,and actinolite;minor minerals include calcite,dolomite,and chlorite.The geological conditions of metallogenic conditions in the study area are complicated.The Archean ancient continental crust in the area was divided into several segments of deep faults with different phases and different properties,and the emplacement of granite grouts and it experienced various complexities such as sinking,undermining and pushover.The geological functions were recombined with different sizes,each with a characteristic granite-silicon-ferro-concrete greenstone belt,and later it was covered by sedimentary deposits formed in the Neo-Proterozoic tectonic basins.The zircon U-Pb age of the surrounding rocks of the Qi Dashan iron deposit reflects that the iron ore deposit formed during the period of 25.5-25.3 Ga and its metamorphic age is about 2.5 Ga.On account of the geological characteristics and genesis of deposits,this thesis based on known geophysical prospecting data and exploratory studies on ore body prospecting projects,carried out studies on the ore-controlling geological conditions and prospecting signs,and summarized the magmatic rock signs,strata and surrounding rock signs in the area.Structural signs and magnetic abnormal signs.Based on the study of ore-controlling geological conditions and ore-prospecting signs,combined with geophysical information such as gravity anomalies and magnetic anomalies,as well as geological information,the ore-searching direction of the study area and prospecting prediction of deep ore body were studied.This thesis considers that the west side of the Qidashan iron ore deposit from line 3600 to line 4500 is to find the favorable position of blind iron ore and delineate two favorable prospecting targets.It is inferred that the west side of the Qidashan ore and the east side of the Chentaigou should be one in the deep,showing a “U” type distribution,which is a one-dimensional structure.At the same time,a comprehensive geology-geophysical prospecting prediction model for this area was constructed to predict the spatial location of the ore body and provide direction for the deep prospecting of the same type of deposit in this area.