Study On The Metallogenic Rules And The Model Of The Zhaishang Gold Deposit, Minxian, Gansu Province

Zhaishang gold deposit, located in the Zhuoluo-State feedlots anticline in thenorthern subzone of the western Qinling mineralization belt, hosts in the interlayeredfractured zone, consists of northern and western belts which occur in Permain andDevonian strata. NW and NNW fault control the distribution of ore bodies or veins.On the basis of summing up the characteristics of fluid inclusion, isotope and REE, thispaper deals with the source of gold, which indicate that the origins of metallogenicmaterials are mainly derived from deep. The host rock of the gold deposits are sandstonesinterbedded with shale and limestone or calcareous slate interrupted by argillaceousslate, which both are hard and soft, controls the development of the ore-bearingstructure. As a whole, the deposits are formed under the coupling interaction amongstrata, fault and magmatic-hydrothermal activities.mineralization rules are as follow:1. Echelon veins distributes along the bend of theanticline;2. ore-bearing structure lies in the hard and soft lithologic boundaries, often inthe carbonaceous or argillaceous slate;3. Segmental gold mineralization concentration;4.Rich ore bodies in northern belt are right-lateral echelons, in southern left-lateral echelons;5. In the projection drawing, ore bodies are pitching western side, or the belowboundaries pitching western in waves;6. ore-bearing structure is left-lateral, shearingcompressive and ductility before the metallogenic epoches; right-lateral, tensor-shearand brittle during the metallogenic epoches; right-lateral, shearing compressive andbrittle after the metallogenic epochs.The fault structural system as follow: GradeⅠore-controlling fault is Minxian-Zhenanfault belt, which is connected with the mantle and is the secondary suture. Grade Ⅱfaults are F9, F1, the structural framework of gold deposits. Grade Ⅲ are F3,F5,F8; F3,F5are controlling the boundary of the north belt, F8is the southern boundary, which is thepath to the deep materials. Grade Ⅳ are the veins in the mine. Those are the ore-guided,ore-matching, ore-bearing structure in the system.The relationship between anticline, faults and ore-forming timing sequence as follows.Interlayered fractured zone, formed by the deformation of Zhuoluo-State feedlotsanticline bump and F1faults belts thrusting-napping, are favorable for the pouring andpositioning of the ore-forming fluid. Grade Ⅱ and Ⅲ fault structural system areconnected to the deep, play a key role in climbing of the deep materials.Its metallogenic model is shown below. Ore-forming materials come from the depth.Under the coupling interaction between structural dynamic and intrusion by hidden rock，Ore fluid formed in the deep climb to the crust shallow along the structural system, andthen Zhaishang gold deposit was formed.The article points out prospecting direction. Firstly, since the deep part is a greatpotential foe mineral resource, deep ore prospecting should be paid more attention.Secondly, the favorable prospecting criteria are the stretch of the north and south ore belts, especially in the stretch to the west. Thirdly, the northeast turnaround of the anti-“s”style Zhuoluo-State feedlots anticline is the surrounding prospecting target area.