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内蒙古赤峰市鸡冠山钼矿区位于内蒙古中部-兴安地槽褶皱区内的内蒙古中部地槽褶皱系，温都尔庙-翁牛特加里东地槽褶皱带，多伦复背斜与敖汉复向斜交汇的部位，两个四级构造单元翁牛特隆起和元宝山坳陷的接壤地带。矿区内地层出露简单，主要是二叠系于家北沟组和第四纪。区内岩浆活动频繁，大面积出露粗面质角砾凝灰岩、粗面岩、花岗斑岩、流纹岩、辉绿岩、石英斑岩和粗面斑岩等。火山穹隆构造和断裂构造是矿区的主要构造类型。鸡冠山钼矿床赋矿岩石主要为花岗斑岩、流纹岩、流纹斑岩、粗面岩、粗面斑岩及辉绿岩，岩石主要属于高钾钙碱性系列及钾玄岩系列，为准铝质–过铝质岩石。样品稀土元素表现为轻稀土富集的配分模式，LREE/HREE变化介于3.94~7.87之间，(La/Yb)N变化介于3.59~8.19之间，除了辉绿岩之外均具有铕（Eu）元素亏损的特点（δEu=0.10~0.68）。微量元素原始地幔标准化图解表现出富集大离子亲石元素亏损高场强元素的特征。岩石中的酸性斑岩为成矿母岩。根据赋矿围岩的地球化学特征，推测中酸性岩岩浆源区为地壳，岩浆演化过程中可能经历了磷灰石、黑云母和斜长石的分离结晶作用，或分异出富含挥发分的P元素的热液，揭示岩浆是在燕山运动强挤压期后的伸展环境下形成的，是亚洲东部大陆地壳的“蠕散”和“伸展”的结果。前人采用锆石U–Pb方法，测得含矿岩体花岗斑岩具有(245.5±2.7) Ma和155~156Ma的年龄，采用Re–Os法，测得辉钼矿具有151~155Ma的成矿年龄。本次研究取自矿床围岩粗面岩的锆石LA-ICP-MS法U-Pb同位素测年结果为377.4±1.6Ma，MSDW=1.09，代表该粗面岩的结晶年龄,说明鸡冠山村钼矿床围岩中至少有一期结晶年龄为晚泥盆世的岩浆岩。矿区的矿石矿物主要为辉钼矿、黄铁矿、闪锌矿、黄铜矿、镍黄铁矿等。脉石矿物包括石英、长石、绢云母、方解石、白云母、黑云母、绿泥石和萤石等。矿石结构复杂，主要有自形一半自形粒状结构、残余结构、交代溶蚀结构、放射状结构等。矿石构造主要有浸染状构造和脉状构造。根据矿石特征把鸡冠山钼矿床成矿期定为气成热液矿化期。根据矿物共生组合及其生成顺序、矿石组构和脉体穿插关系，可以把鸡冠山钼矿成矿作用从早到晚分为3个阶段：早阶段为硅化阶段，中阶段为主成矿阶段，晚阶段为石英一碳酸盐阶段。矿体的围岩蚀变主要有钾化、绢云母化、硅化、高岭土化和萤石化等。其中硅化、绢云母化和萤石化等与钼矿化关系较为密切。根据矿区含矿石英脉中流体包裹体均一温度的分布，成矿可分为早、中、晚三个阶段，不同成矿阶段流体包裹体的均一温度不尽相同：早阶段流体包裹体均一温度在478.6℃以上，盐度较高，本次研究测得盐度为11.36~60.85wt%NaCl之间；中阶段为主成矿阶段，流体包裹体均一温度182.6~457.6℃之间，盐度为5.25~37.64wt%NaCl之间；晚阶段流体包裹体均一温度范围为108.7℃~152.6℃，盐度为5.70~9.47wt%NaCl之间。通过计算可知，成矿压力范围为29MPa～146MPa，平均为91.8Mpa；深度介于0.99km～4.86km，平均深度3.06km。鸡冠山钼矿成矿流体主要来自岩浆水，大气降水影响较小。鸡冠山钼矿床为Climax型斑岩型钼矿床，酸性斑岩为其成矿母岩，根据酸性斑岩的构造环境及岩浆源区推测矿床成矿源区为下地壳，是在燕山运动强挤压期后的伸展环境下形成的，是亚洲东部大陆地壳的“蠕散”和“伸展”的结果。The Jiguanshan molybdenum deposit of Chifeng City, Inner Mongolia is located in the central InnerMongolia Geosynclinal fold system of the Tianshan-Central Inner Mongolia–Xing’an geosynclinal foldregion, Wenduermiao-Wengniute Caledonian geosynclinal fold belt, the intersection of the Duolunanticlinorium and Aohan synclinorium, the border zone of two four level tectonic units Wengniute Upliftand Yuanbao mountain depression. Mining area stratum exposure is simple, mainly North Ditch group ofthe Permian and quaternary.There were Frequent magmatic activitives in this region, where have large areatrachytic breccia tuff, trachyte, granite porphyry, rhyolite, quartz porphyry and trachyte porphyry etc..Volcano dome structure and fault structure are the main structures of the mining area.The Jiguanshan porphyry molybdenum deposit’s ore-bearing rocks are mainly granite, rhyolite,rhyolite porphyry, trachyte andesite, trachyte porphyry and diabase. They belong to high-K calc-alkalineseries and shoshonitic series, and lie between metaluminous field and peraluminous field. Rare earthelements of samples showed a distribution pattern of enrichment of light rare earth, with LREE/HREEratios of3.94~7.87and (La/Yb)Nratios of3.59~8.19. in addition to diabase, all the rocks show acharacteristic of loss of europium（δEu=0.10~0.68）. Trace elements spiderdiagram of samples shows acharacteristic of enrichment in large ion lithophile element sand loss of high field strength elements. Theacidic porphyry in the rocks is the ore-forming parent rock.According to the geochemical characteristics ofore-bearing rock, we speculate the source region of intermediate and acidic rock’s magma is crust, theremay be fractional crystallization in magma evolution, the evolution process may include the fractionalcrystallization of apatite and biotite, or the differentiation of hydrothermal solution of phosphorus rich involatile matter. Combining with regional geological evolution and metallogenic characteristics of porphyrymolybdenum deposit, we Reveal the magma forms in a extensional environment after the strong extrusionstage of Yanshan movement, or forms in the " creeping " and " stretch " process of East Asia continentalcrust.predecessors measured the ore bearing rock granite porphyry’s age is (245.5±2.7) Ma and155~156Ma by zircon U-Pb method, the mineralization age of molybdenite is151~155by Re-Os method. Thecountry rock trachyte’s Zircon LA-ICP-MS U-Pb isotope dating result is377.4±1.6Ma, MSDW=1.09, inthis study represents the trachyte’s crystallization age, illustrate the surrounding rock of the Jiguanshan Modeposit has at least a magmatite whitch crystallization age is Late Devonian.Ore minerals of the mining area are molybdenite, pyrite, sphalerite, chalcopyrite, pentlandite etc.. Thegangue minerals include quartz, feldspar, sericite, calcite, muscovite, biotite, chlorite and fluorite etc.. Ore