• 责任者：Song Mingchun (Shandong Provincial Bureau of Geology and Mineral Resources ; Jinan 250013 ; China) ; Song Yingxin
• 刊名：Geochimica
• 出版年：2013
• 卷期：42(3)
• 关键词：金矿 ; gold ores ; 矿床地球化学 ; mineral deposit geochemistry ; 山东 ; Shandong Province
• 页码：p.274-289
• 图表：illus., 6 tables, 37 refs.
• 分类号：1001
• issnNo：ISSN0379-1726
• isbnNo：CN44-1398/P

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‰ δ^34SCDT, indicating a mixed source. Their δDV-SMOW and δ^18OV-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.