The Mineralization And Geochemical Features Of Stone Forest Park Mo(W) In Xiaoxing'anling

The study area is loacted in the north of polymetallic ore belt of Xiaoxing'anling– Zhangguangcailing in northeast of Xiaoxing'anling area . China is devided into six mining areas (belts) by tectonic– magmatic and rock types and molybdenum mineralization with it's element association. Heilongjiang– Jilin metallogenic area is one of the most important metallogenic belts. And the main types of deposits are skarn,porphyry copper - molybdenum ore, molybdenum-polymetallic etc. i.e. Duobaoshan, Cui Hong Hill,Luming and Huoji river, etc. At present, the researchs for metallogenic theories and mineralization rules are very weak and many of them are production and basic researchs. At the metallogenic epoch aspect, the study for the the epoch of ore-hosted rock is the Main part without any direct results for the age of ore and minera. As to the types of causes, most experts considered that the deposit of Huoji river and Luming are types of porphyry. But according to the observations outside, large quartz vein-type mineralization whose feature is Hydrothermal vein-type had been discovered in the molybdenum deposit of huoji river and the wolfram -molybdenum ore spots in south mountain of stone forest park.The tectonic setting of the wolfram -molybdenum ore spots .i.e. tectonic environment and exposed strata of mining and Magmatic rocks and tectonic are similar with large molybdenum mine of Huoji river and molybdenum Copper mine of Luming. So contrast with molybdenum mine of Huoji river and molybdenum Copper s mine of Luming, the result has important significances for further exploration in the wolfram -molybdenum ore spots in south mountain of stone forest parkThe main study object of this paper is the wolfram -molybdenum ore in south mountain of stone forest park, and made a comparative study on large molybdenum mine of Huoji river and medium-sized molybdenum mine of Luming. Then we probe mineralization and geochemistry of the wolfram -molybdenum ore spots in south mountain of stone forest park. And it is Investigated about wolfram -molybdenum mineralization and geochemistry in xinqing district in Xiaoxing'an area.The main results and understanding by the researchs of regional geological setting and regional geochemical characteristics and deposit geological features and the characteristics of fluid inclusions and deposit genesis and the comparative chronology ,are as follows:①Molybdenum mineralization is closely related with the acidic intrusive rocks. The study results show that the ore-hosted rock of the minings in Huoji river and Luming is the biotite monzogranite, and wolfram -molybdenum ore spot in south mountain of stone forest park it is alkali feldspar granite. The all of the ore-hosted rocks were silicification, potassic, phyllic and molybdenite mineralization strongly. The main ore mineral assemblages are: molybdenite, pyrite and chalcopyrite②The REE curve of the ore-bearing rock is a generally right-wing type one. The curve of HREE is relatively flat or slightly left-leaning like asymmetry "Seagull"-type. On the REE the element Eu deficit heavyly. In spider, the curve is right-wing type one. The HFSE are more enrichment, and LILE like Rb,Ce are enrichment but K,Ba,P and Ti are relatively more losses. From the trace element spider diagrams we can know that the curves of the three mines are the same modles totally. And the result showed that their ore-hosted rock should have the same diagenetic environment.③The research about fluid inclusions in quartz showed that ore-forming fluids more uniform system of H2O-NaCl salt solution without CO2. Before mineralization, the fluid with the feature of high temperature and high salinity represents the characteristics of the early evolution of magmatic hydrothermal. During the mineralization, the type of fluid is mid-low temperature and mid-low salinity one. And the general characteristics of them is that high temperature-high salinity mixed with low temperature -low-salinity fluid.④The test result about the single zircon age of ore-hosted rock of molybdenum deposit by the way of LA-ICP-MS showed that the diagenetic age of it is between 179.5±1.1Ma～207±3.1Ma. the test result on isotope Re-Os of the sample of the molybdenite ore minerals showed that the diagenetic age of it is 208.9±3.2Ma. according to the results, we can know that diagenesis and mineralization occurred in the Late Triassic - Early Jurassic.⑤The molybdenum deposit-forming materials are mainly coming from the magmatic fluid which formed by ore-hosted rocks. and the main source of water is magmatic water with part of the ground water and rainwater. The high temperature and high salinitymagmatic fluid takeing along mineralization migrated upword along regional faults and micro-cracks in rock driven by tectonic stress and temperature gradient. Meanwhile, the groundwater and rainwater which infiltrated along the tectonic fracture is heated up. The rock-forming materials in the ore-hosted was leached and extracted and then the low temperature -low salinity fluid enrichmented minerals such as Mo was formed. two ore-forming fluids were mixed in the shallow crust.and because the temperature and pressure get low and physical and chemical conditions had changed, the ore-forming fluids precipitated enrich in the fractures and micro-cracks in the rock. Then the quartz vein and micro-disseminated mineralization were formed. And all of above reasons lead to the mineralization of mixed ore with the features of hydrothermal veins type and porphyry type.