Geological Characteristics And Prospecting Of Habuqige Gold Polymetallic Deposit In Doulan County,Qinghai Province

The study area is located in the northeast edge of Qaidam basin and belongs to the Kunlun metallogenic province.It spans the Pb-Zn-Mn-Cr-Au-muscovite metallogenic belt??-24?in the northern margin of Qaidam basin and the Li-B-K-Na-Mg salt gypsum-oil-natural gas metallogenic area??-25?in the Qaidam basin.The strata are located in the junctional zone of the Qinqikun orogenic system and the North Qaidam margin of the ophiolitic mélange zone.The strata in this area belong to the Qinqikun stratigraphic region,including the northern margin of Qaidam and the Qaidam basin.The strata mainly expose Cambrian-Ordovician Tanjianshan Group,Middle-Late Devonian Yaoniushan Formation,Early Carboniferous Huaitoutala Formation,Pliocene Youshashan and Shizigou Formation,and Quaternary.It belongs to the tectono-magmatic belt of Qinqikun and northern margin of Qaidam magmatic belt.Regional magmatism is not widespread and intrusive rocks are sporadically exposed.They are distributed from ultrabasic rocks to acidic rocks on a small scale and occur as small stocks or veins.The metamorphic rocks in this area are divided into Tanjianshan metamorphic belt and northern Qaidam metamorphic belt,which mainly underwent two stages of metamorphism:Caledonian and Variscan.The regional fold structures are mainly developed in the Middle-Late Devonian period.Among them,the Amunik compound syncline runs across the whole area and is the largest and most widely distributed fold structure in this area.Regional faults are characterized by NW-SE brittle faults,which are distributed in the same way as rock strata,and have the characteristics of large scale,long extension and multi-stage activities,thus constituting the regional tectonic framework.Gold deposits such as Kongquegou,Hangyagou and Kongquegoukou lead-zinc deposits have been found in the study area.Large and medium-sized gold and polymetallic deposits such as Dadakenwulashan polymetallic deposit and Amunik molybdenum deposit are developed in the region.Existing exploration results confirm that the gold and polymetallic mineralization in the area is mainly controlled by Cambrian-Ordovician,Devonian epimetamorphic volcanic-sedimentary rock strata,NW-SE trending faulted structures,Compared with the typical polymetallic deposits in Dadakenwulashan,the metallogenic tectonic setting and metallogenic geological conditions are similar.They have great prospecting potential for medium low temperature hydrothermal soiution gold and polymetallic type minerals.The ore prospecting indicators are obvious,and two magnetic anomalies of C7 and C9 are found through high-precision magnetic survey?1:50,000?.According to stream sediment survey,six synthesis anomalies were circled,including HS³_b2,HS⁵_b3,HS⁶_b3,HS _c⁷,HS _c⁸and HS _c⁹.A preliminary examination is carried out on the synthesis anomalies of 1:50,000 water systems,including HS³_b2 and HS⁵_b3.Through 1:10,000 soil surveying,it was found that the anomalies had good reproducibility,and 11 synthesis soil anomalies were circled out.These anomalies had the characteristics of wide range,high peak value,obvious concentration center and close overlapping of anomalies.The characteristics of anomaly zoning are obvious,showing the axial zoning pattern of Au,As,Sb-Zn,Pb-Mo,Cu-Pb,Zn-Au,As and Sb?beaded along NW structural direction?,which is consistent with the high magnetic anomaly in this area.Volcanic rocks of the middle Late Devonian Maoniu formation?D₂-₃m³?are developed in the anomalous area,and Devonian continental volcanic magmatic rocks are exposed.There are three groups of faults:NW-SE,NEW and NE-SW.The anomalous occurrence is controlled by the NW-SE trending structure and the distribution characteristics of the strata of the middle Late Devonian Maoniu formation?D₂-₃m³?.In the study area,silicification and limonitization were found in the middle Late Devonian Maoniu formation?D₂-₃m³?,and two alteration zones were circled.By comparing with the gold and polymetallic deposits in Dadakenwulashan,Kongquegou,Hangya,etc.it is shown that the study area has similar metallogenic geological background,ore-controlling factors and prospecting indicators,which indicates that the area has better prospecting potential for gold and polymetallic deposits.According to the development degree of metallogenic geological conditions and the development characteristics of prospecting indicators,Three prospecting areas are delineated,respectively A1,A2 and A3.The prospecting potential is preliminarily analyzed,and favorable prospecting target areas are put forward,which provide important basis for subsequent exploration deployment and verification of exploration engineering.