We studied geochemical features of drillhole specimens between depths of 349.12-1212 m in the deeply-seated gold deposit of Jiaojia gold ore field.Petrochemical composition of altered rocks in the deeply-seated gold deposit is similar to that of granite.Strongly altered rocks belong to ultrapotassic and weekly altered rocks belong to shoshonite series.Through comparison of petrochemical composition of altered rocks and granite,we find that the alteration zone gained SiO2,H2O,K2O and Fe2O3 but lost Al2O3,CaO and Na2O during alteration.Trace elements characteristics of altered rocks are similar to that of granite and adakite.Sr,Ba,Zr and Hf contents of the altered rocks are lower than those of the granite,and Rb contents are higher.The altered rocks are relatively enriched in LREE,depleted in HREE,and have positive Eu abnormity.The sulfur isotope composition of the gold ore ranges between 11.08‰-12.58‰ δ34SCDT,indicating a mixed source.Their δDV-SMOW and δ18OV-SMOW values range from-83.68‰--116.95‰ and 12.04‰-16.28‰,suggesting that they were mainly derived from meteoric water or mixed with magmatic and meteoric water.The fluid inclusions are dominantly saline water inclusions,followed by H2O-CO2(±CH4) and pure CO2 inclusions,occasionally with daughter mineral-bearing inclusions.Fluid immiscibility is crucial characteristics of deeply-seated gold ore.From granite to ore body,decrepitation curves of fluid inclusions show negative anomalies of vapor aureole occurring together with increasing of alteration and mineralization.This paper proposes that fluids derived from the Early Cretaceous Weideshan granite caused the gold mineralization,the conditions of which are different for altered-rock type and quartz vein type gold deposits in the Shandong Peninsula.%在开展焦家深部金矿找矿的同时,采集349.12～ 1212 m深度钻孔岩芯样品,研究了矿床地球化学特征.深部金矿床近矿围岩的岩石化学成分位于花岗岩成分范围内,具有钾玄岩系列和超钾质系列特点.将蚀变岩石与花岗岩的成分相比较,得出蚀变过程中加入、带出的元素,SiO2、H2O、K2O和Fe2O3加入到蚀变带内,而Al2O3、CaO和Na2O等组分被带出.蚀变岩与花岗岩微量元素特征相似,具有埃达克岩的特征,从花岗岩到蚀变岩:大离子亲石元素Sr含量明显降低,Ba含量呈降低趋势,Rb含量呈升高趋势；高场强元素Zr、Hf含量呈降低趋势.稀土分布模式总体表现为右倾型,轻稀土分馏明显,重稀土较平坦,多具Eu正异常.金矿石硫同位素值较稳定,δ34SCDT=11.08‰～12.58‰,具有混合硫特征.氢同位素组成δDv-sMOW=-83.68‰～-116.95‰,氧同位素组成δ18OV-SMOW=12.04‰～16.28‰,显示了以大气降水为主或岩浆水与大气水的混合水特征.流体包裹体组成主要为H2O(盐水)包裹体、其次为H2O-CO2(±CH4)包裹体和纯CO2包裹体,偶见含固相(石盐或方解石)的水溶液包裹体.流体不混溶是深部金矿床流体包裹体的重要特征.从花岗岩到矿体,随着蚀变和矿化作用增强,包裹体爆裂曲线显示了负的蒸发晕和负异常.研究认为,早白垩世伟德山花岗岩岩浆活动所引起的流体活化是导致金矿成矿的直接原因；胶东蚀变岩型金矿与石英脉型金矿稳定同位素和流体包裹体地球化学特征有较大差异,指示两者的成矿条件不同.
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