| The eastern Jilin-Heilongjiang provinces located at the intersection area of Siberia plate, the NorthChina plate and the Pacific plate is one part of the eastern Mongolia-Hinggan orogenic belt,stretching across the metallogenic domains of Paleo-Asian Ocean and Circum-Pacific and experiencedthe transition and superposition of these two metallogenic domains. The study area is composed of theJiamusi massif, the Yanbian massif and the Wandashan accretionary belt and characterized by thecomplex and special tectonics and magmatisms. Therefore, this area have been the focus of studiesconcerning the geodynamic evolution besides the Tibetan Plateau, in particular the temporal-spatialstructures of China continental lithosphere and interactions between different spheres in NE China. Thedistinct geological evolution and multi-structural magmatic events in the study area can provide wellmetallogenic factors for the endogenic metal deposits. According to incomplete statistics, there arealmost100deposits and more than30deposits are big-and middle-size, showing the hugemineralization potential and exploration prospect.The NE China, Inner Mongolia, the eastern Mongolia and the eastern Russia is characterized bythe widespread Phanerozoic granitic intrusions, which can be described as Large Granitic Province.Each micro-massif were matched together to be the united plate of Jiamusi-Mongolia block in earlyPaleozoic which verified of the magmatite distribution in each unit. Mafic-ultramafic intrusions aremuch less than intermediate-acid intrusions in the study area which intruded into Cambrian strata asbatholiths; For the crystalline basement disjoined, the silent stage of magmatism lasted from late EarlyPaleozoic to early Late Paleozoic; At the latter stage of Late Paleozoic, the collision of micro-massif in study area formed gneissic granodiorite-monzogranite rock association in Heihe-Nenjiang collisionzone and quartz diorite-monzonitic granite-gneissic granodiorite rock association in Yichun-Hegangarea; The West Lamulun River-Changchun-Yanji plate suture zone closed at the end of Late Paleozoiccaused the ensuing extensive mafic-ultramafic magma activity along the zone which representative theregion became to post-collisional extension setting. Affected by the subduction of the Pacific plate, theNNE-NE trending early Jurassic granite are widespread in the study area, concluding rock associationof quarta diorite-granodiorte-monzonitic granite, rare diorite and alkali granite; Late Yanshanin,lithosphere is extending and thinning, and volcano rocks are developed in the study area. The intrusiverock during this period are diorite, porphyrite diorite, granodiorite-porphyry and granite porphyry.This paper determined the relationship between the magmatisms and metallogenesis andsuggested four peaks of magmatisms and metallogenesis:(1) the Hercynian orogenic gold deposits(260-250Ma) show close relationship with magmatism in transitional tectonic setting betweensyn-collision and post-collision;(2) the Indosinian orthomagmatic ore deposits (230-210Ma) showclose relationship with mafic-ultramafic magmatism in post-collision extensional setting;(3) porphyrymolybdenum deposits and skarn deposits of the Late Triassic to the Early Jurassic (200-170Ma) whichformed in continental arc tectonic setting triggered by slab subduction;(4) the Late Yanshanian largemineralization caused by the tectonic extension (133-106Ma). Combined with the previous researches,we found that the age of Phanerozoic metallogenesis are in consistent with the peaks phases ofmagmatisms in the eastern Jilin-Heilongjiang provinces and the latter delayed for almost10Ma.Based on the field work and laboratory study, this study presented new understandings on thegenesis types and characteristics of deposits in the eastern Jilin-Heilongjiang provinces:(1) in the past,the Sipingshan gold deposit was defined as the hot spring type. According to our research, wesuggested that the Sipingshan gold deposit should be the symbiotic deposit of continental hydrothermalexhalative sedimentary type and hypabyssal epithermal type;(2) the genetic type of Jinchang golddeposit should be a transition type of porphyry to epithermal;(3) Hekoulinchang tin deposit in ourstudy area was first found and we suggested that this tin deposit could be one part of the Sikhote-Alintin province and its host rocks have close relationship with rocks in the tin province.Furthermore, this paper summarized the spatial distribution relationship between the endogenicdeposits and the magmatic rocks. Obviously, the magmatisms control the distribution of deposits. Based on the characters of regional distributions of magmatisms and deposits, we divided threeore-concentrated areas:(1) the Lesser Hinggan Mountains-Zhuangguangcai Mountains metallogenicbelt;(2) the Jiamusi-Khanka metallogenic belt; and (3) the Yanbian metallogenic belt.Combined with the magmatisms, the distributions of deposits and the metallogenic types in theeastern Jilin-Heilongjiang Provinces, we suggested two exploration areas: the Wuyiling-Yichun-Tonghearea in Heilongjiang Province and the Shulan-Daheishan area in Jilin Province. Yichun and Bindongare well areas for the Skarn type deposits and the focus exploration regions are:(1) Gongpengzicopper-zinc mineralization area;(2) Qiupigou copper-zinc mineralization area;(3) Yicuomaoiron-copper polymetallic mineralization area;(4) Tumenling polymetallic mineralization area. Theepithermal Au-Ag deposits mainly distributed in the southern Heihe-Xunke-Jiayin area, exposing in theLate Yanshanian volcanic rock belt trend NW. The porphyry-epithermal type Au-Cu deposits mainlydistributed around the complex tectonic-magmatite zone trend EW, the Mesozoic volcanic basin, upliftzone and the secondary uplift zone in rifted-basins.Summing up the above, this study preliminary presented four mineralization prospects in theeastern Jilin-Heilongjiang provinces:(1) the Yichun-Bindong-Jizhong porphyry-and fine vein-typemolybdenum ore and skarn-type iron-copper mineralized concentration camp;(2) Sandaowanzi-Dongan-Gaosongshan-Wulaga gold (silver) mineralized concentration camp; the Jinchang-Xiaoxinancha porphyry-epithermal type gold-copper mineralized concentration camp; and (4) theYantongshan-Hongqiling ore prospecting region in the Panshi city of Jilin Province. |
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