| The studied region is located in the Joint spot between south of palae- Siberia plate,Erguna fold,Inner Mongolia- Daxinanling fold and Upper-Heilongjiang down faulted basin. Its regional geologic settings are very complicated including diverse regional strata, magmatic rocks and structures.Regional magmatism was strong also, and every epoch or type of magmatic rocks occurred in whole studied region.The volcanic rock of Stage of Yanshan play an important role in the region.The distribution of strata here is extensive but piecemeal.The strata appear from Precambrian to Cenozoic except upper Cambrian and mid carboniferous. The strata of Mesozoic and Cenozoic are most developed.Northern studied region represents as Mesozoic tectonic that belonged to Heilongjiang down faulted basin on Erguna fold belt of Mongolia fold system.By their extent of development,they are tectogenesis of fracture,tectonic of fold,tectonic of volcano and they get the characters of long term development and multiple deforming.The general shape of the fold tectonic is synclinorium and the synclinorium is broad,slowly varying and east-west strike.The fracture of the region are regional tectogenesis of east-west strike,north-east strike,north-north-east strike,north-west strike and north-north-west strike.The southern fracture is generally well developed.The fold tectogenesis of the west region is mainly belong to late-Paleozoic-Era and Precambrian tectogenesis and generally welldeveloped.There are three positions of the fold tectogenesis :Bielahan anticlinorium,Baikalushan anticlinorium and Bulujiyashan syncline.The fracture tectogenesises mainly are north-east strike and north-west strike chiefly developed in Mesozoic.The magma activity here are very frequency and the intrusive rock is also very well developed.There are super-mafic,mafic rock and granitic rock.The medium-acidic,acidic granitic rock is the most developed of all. The distribution of intrusive rocks are variance.The southern area is much more biger.The vein rock here are well developed and mainly exist in the south region.The distribution of volcanics in the studied region is extensive and general outputted in Upper Jurassic and Lower Cretaceous.The volcano activities in the studied region are multiple, encircling, complicated types.Based on the above research, we analyzed regional metallogenic conditions from geology, geophysics and geochemistry. Considering regional strata, some source beds with ore-bearing strata controlled apparently metallogenesis. The strata formed some favorable source beds and established substantial foundation for later diplogenetic metallogenesis (e.g.Bailahe ore field)or formed directly industrial ore deposit(e.g.Laogou ore field).Considering regional magmatism, it could provide substance source, thermal source, and metallogenic location.They could form hydrothermal vein, skarn, porphyry, or SEDEX deposits. And volcanic or volcaniclastic rocks were important source beds, while granitoids had specializations.Considering regional tectonics, regional NE faults controlled gold metallogenic belts, and the crossover point of NW faults and NE faults caused pyrometasomatic deposits . Porphyritic rocks and Vein rocks are relative with porphyry copper in space. Considering geophysics, pyrometasomatic metallogenesis was related with lower density of gravitational anomaly area in the west-south of the studied region,and mid-low gradient belts and low value regions of aerial magnetometer anomalycould direct the ore region.Then metallogenic regularities were discussed in the studied region. Major metallogenesis focused on major Yanshanian, minor Jinning, and few Caledonian. According to geologic settings, distribution regularities of ore deposit and major metallogenesis in metallogenic belts, it was thought that typical deposits in metallogenic belt of this region is pyrometasomatic deposit . On the basis of analysis of predecessor's materials and our field survey, we discussed geology of ore fields, geology of deposits,genetic model, and metallogenic potential of deposits for all the above typical deposits, and determined their genetic types.In addition, we finished a spatial database of the studied region. The database consists of basic geographical map, digital geological map, ore occurrence, geochemistry and geophysics database etc. So we could utilize GIS technology to manage polygenetic data in the database, and made GIS-based mineral resources assessment in the region. At first, a regional deposits exploration model was proposed by us. It was shown that metallogenesis in the studied region was located mainly commodities focused on Au, Cu, and Pb, Zn. Then we tried to use data-driven weights of evidence modeling to make GIS-based mineral resources assessment for them. At first we manipulated weights for every evidential themes derived from each corresponding exploration model of Au, Cu, and Pb, Zn deposits. Second we made weights mean measures of metallogenesis, metallogenic regularities, ore-forming conditions and conserving condition of ore deposits. At last, we calculated posterior probabilities for Au, Cu, and Pb, Zn deposits. Then according to this results, we delineated some prospect areas for Au, Cu, and Pb, Zn deposits respectively. Then we classified them with grade Aand B in turn according to double integral (this value equal to sum) of posterior probabilities of the predicted ore bearing area in every prospect area. In a word, it was shown that achievement could be maken using data-driven weights of evidence modelingin the studied region is great. Whereas its fundamentality is researching into metallogenic regularities in details and digital information of large quantity.
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