Structural Features And Ore-controlling Rules Of Linjia Sandaogou Gold Deposit In Eastern Liaoning

The Linjia Sandaogou gold deposit is an altered rock type gold deposit in Qingchengzi Ore Concentration Area of Liaodong.The main ore controlling fault in the mining area is the ne bedding slip fault.In this article,based on the basic theory and method of ore field structure,combined with the field survey and previous research results,the structure related to mineralization in the mining area is divided into stages,and the characteristics of geometry,kinematics and dynamics are analyzed to find out the evolution process of the structural stress field in the mining area,determine the rule of structural ore control,and further predict the favorable mining area.The main achievements of this article are as follows:(1)The bedding slip faults in the mining area are both ore guiding structures and ore bearing structures.The evolution process of the main stress direction of the mining area is from the south to the north before mineralization,from the East-West to the north-east during mineralization,and from the south to the north after mineralization.The structural ore control model is a set of strata detachment fracture secondary fracture joint rock control ore control structural system.(2)According to the investigation of different parts of the ore body,the characteristics of structural rock control and ore control are divided.The north west side of the mining area is a gently inclined layered ore body,and the middle and south east sides of the mining area are horizontal thick layered ore bodies.The mineralization of gently inclined stratoid ore body is related to lamprophyre,while that of horizontally thick stratoid ore body is related to lamprophyre and granite porphyry.(3)There are the following rules of structural ore control in Sandaogou,Linjia:(1)the ore is controlled by structural plane,and the thickness of horizontal thick layered ore body increases at the change of tendency,the intersection of faults with different tendency,and the change of ore body occurrence.The thickness of the gently inclined layered orebody is stable;(2)the ore is controlled by multi-level structure,which shows that the ore field is controlled by Jianshanzi fault and jiaojiabaozi syncline,and the ore body is controlled by the bedding detachment structure;(3)the ore body No.5 is favorable for mineralization in the footwall of vein rock and the footwall of detachment fault;(4)the horizontal thick layered orebody is inclined from the northeast to the southwest.The gently inclined bedded orebody inclines to the northwest and lies to the northeast;(4)Based on the data of mining area and the field investigation,the gold grade,thickness characteristics and their relationship of No.5 orebody are revealed,and the mineralization rules of No.5 orebody is obtained.The horizontal thick bedded orebody has higher grade and lower thickness.The gently inclined stratoid orebody has low grade and high thickness.The ore body line is rich in Northwest and poor in South and East.The mineralization index indicates that the ore body is rich in the NE direction along the strike and rich in the NW direction along the dip.(5)According to the study of mineralization rules of orebody,it has high prospecting potential to delineate the north-east part of gently inclined stratoid orebody.