| In recent years, most people paid special attentions to gold and multimetal deposits formed in the Proterozoic era in recent years. Many important large to supper-size ore deposits of Fe,Mn,Pb,Zn,Cu,Ni,Au,U,P,B,Co as well as REE have been discovered in Proterozoic era. It's considered that the Proterozoic (especially Paleoproterozoic) is one of the most important mineralization periods in the world. Qingchengzi metallogenic belt is located in the middle part of Liaodong rift. The Proterozoic stratiform rocks are widely distributed in this belt. 12 medium to large-size lead-zinc deposits proven reserves have been discovered in round about 20 square kilometers which includes the Qingchengzi, Zhenzigou, Nanshan, Benshan and so on. In the phase, one large-size silver deposit(Gaojiabuzi), one large-size gold deposit(Xiaotongjiabuzi) and many medium-size gold deposits have been discovered in Qingchengzi metallogenic belt where 209 tons gold and 1139 tons silver proven reserves and many preferred exploration areas. This paper takes Au, Ag deposits in Qingchengzi metallogenic belt as the research objects. On the base of previous work, the author chose the tectonic environment, ore-forming condition and ore-forming fluids as the study emphases of this paper, discussed ore-forming fluids characteristics and genesis of Au and Ag deposit and acquired a systematically recognitions to the Qingchengzi metallogenic belt as follows: 1. The research region is located in Liaodong rift, North China craton. During early Proterozoic, the rift formed huge thick metalmorphic rock series of Liaohe group along with the extension and rifting, steep dipping, compression and strike-slip, compress and uprising. Metamorphism-deformation in late Paleoproterozoic era, magmation and tectonism in the Mesozoic provided plenty material and energy for the Qingchengzi B, Fe, Pb, Zn, Ag, Au deposits et al., 2.The Liaohe group mainly occurs Langzishan suite, Lieryu suite, Gaojiayu suite, Dashiqiao suite and Gaixian suite. The protoliths of the group underwent greenschist to amphibolite facies metamorphism and is composed of granulites, marbles interbedding with schists. The gold and silver deposits in Qingchengzi minerallgenic belt mainly occurred in Dashiqiao suite, especially in the member 3. These deposits are not occur in all stratum of Dashiqiao suit, but occur in certain rock assemble which are the secondary basin ( Sanjiazi-Fangjia neritic marine basin ) in Liaodong rift. 3. Gaojiabuzi silver deposit is better mineralization perspective in Qingchengzi minerallgenic belt. The orebodies are mainly bedded, lentoid or lentiform and occurred in layer 4 and 5 of member 3 in Dashiqiao suite. The main types of silver deposits in this region include quartz vein of silver-bearing, fracture marble of silver, lead, zinc-bearing. The texture and structure not only remain the stratification structure but also formed many miarolitic structure or crystal structure which are formed by late hydrothermal. The metallogenic epoch can be classicified into regional sedimentary-metamorphism stage and hydrothermal alteration stage. The latter can be subdivided into quartz–pyrite stage and natural silver stage. The hydrothermal alteration phase is mainly mineralization in this deposit. Late hydrothermal brought large alteration and formed abundant of pyrite veins, milkiness quartz veins and many miarolitic structure or crysta structure in this area which contribute to the formation of silver deposits. 4. Xiaotongjiabuzi-Linjia gold deposits occur mainly within marble, low-grade granulite, mica schists interlayered with sillcalite near the junction of upper Dashiqiao suite and Gaixian suite. As huge-size gold deposit of xiaotongjiabuzi an example, three gold mineralization (I,I-1,II) belts occurred in layer 4 and 5 of member 3 in Dashiqiao suite and the junction with Gaixian suite. The orebodies are mainly like bedded, lentoid in those layer. The metallogenic epoch can be classicified into regional sedimentary-metamorphism stage and hydrothermal alteration stage. The former is mainly arsenopyrite-gold mineralization, the latter are subdivided into quartz–pyrite stage and quartz–carbonatite stage. Amount of banding and bedding structures can be found in ores and stratum in gold deposits. These structure indicate more stronger sedimentary, metamorphism-deformation than late hydrothermal alteration in this gold deposit. Many sulfide occurred in the layer with banding and bedding indicating structures the characters of strata-bound type. 5. Fluid inclusion studies on Au, Ag deposit in Qingchengzi metallogenic belt showed that clear differences in fluid inclusion features exsit between gold deposits and sliver deposit. There are mainly have three types of primary fluid inclusions exsit in mineral quartz of Gaojiabuzi sliver deposit, which are: aqueous two-phase, carbon dioxide-bearing three-phase, carbon dioxide. The homogenization temperatures range from 119℃to 340℃, salinity ranges from 5.0 wt%NaCl to 12.5 wt%NaCl. The characters give us the conclusion that the ore-forming solutions are of immiscible NaCl-H2O-CO2 system. The ore-forming fluids underwent immiscible process to miscible process which brought positive influence to sliver deposit to settle and further-concentrate. The comparability of immisciblity system exsit between Xinling and Gaojiabuzi fluid inclusions, that give us a conlusion that ore-forming fluids mainly comes from magma stage. At xiaotongjiabuzi and Linjia gold deposits, the fulid inclusions are mainly aqueous two-phase, single liquid phase and a small quantity of carbon dioxide-bearing three-phase, carbon dioxide. The homogenization temperatures range from 110...
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