Geological Structure And Rock And Ore Controlling Function Of Yuerya Gold Mine In Kuancheng County Of Hebei Province

Combining with a large number of field geological phenomenons and previousliterature datas，this paper analyzes the geological characteristics Yuerya gold depositin Kuancheng county，mainly including stratum and rock combination， ore veincharacteristics，plane and profile shapes of rock mass，structure，ore controllingfunction and geological tectonic evolution.In the region of eastern Hebei province， the stratums mainly consist ofmetamorphic rocks in Archean and sedimentary rocks in Middle-Late Proterozoic; thestructure includes the dome of Qianxi rocks in Archean， the fold belt of Zunhuarocks in Archean and the Malanyu anticlinorium in Yanshanian; the magmatic rocksare mainly granitic intrusive rocks in Indosinian and Yanshanian.The area of Yuerya gold deposit is controlled by the extrusion tectonic stressfrom North West to South East and basement structure， The rudiment of Yuerya-Xiabancheng fault-fold belt forming in the early Mesozoic-late Indosinian， to theearly Yanshan period， Yuerya anticlinorium basicly finalized the design. Yueryaanticlinorium controls the main body form of granite rock mass，rock extensiondirection is to NE; At the same time the sub-tissue anticline controls the border of therock， lead to the border with a harbour shape.Rock mass be controlled by the ore ofYuerya anticlinorium and by fractures within deposit， In the plane，the rock mass islike a olive， inflated intermediate and narrow in both ends.In profile，like aobsequent water droplet.A lot of research activities showed that there are two times magma intrusionactivities in Yuerya gold deposit. The white granite formed in the first time， the redgranite formed in the second timeSome previous considered that the metallogenic age of Yuerya gold deposit isabout174Ma，at the same time，with the method of Re-Os isotope analysis ourprojiect team obtained the metallogenic age of Yuerya gold deposit is about167~168Ma， so the metallogenic age infered between164Ma and174Ma isreasonable. The gold deposit is effected by five groups of fracture，among which the fractureto NE， the fracture to NNE and the fracture to ENEare the fractures in metallogenicperiod，are the main controlling fault of mineralization， more than90%of vines andore body are filling in the crack to NE.95%of the auriferous quartz veins towards NE， tilt to the north west，the digangle are between10°and65°，the tilt angle of the shallow ore body is steep，to deepthe tilt angle is slowly steep. This series of veins are most like layer，the form is flat，In the space，these veins are parallel to each other，and arranged isometricly by50metres or multiple of50metres. The mineralization of the thick layer of quartz vein islow， but the quartz fine veins and broken surrounding rock is higher.