【摘要】 黄沙坪矿床是南岭成矿带中段具有代表性的矽卡岩型钨钼多金属矿床。为确定矽卡岩中石榴子石的成分及变化特征，对石榴子石开展了电子探针主量元素研究。结果表明，石榴子石成分主要为钙铁榴石和钙铝榴石。从核部至边部钙铁榴石含量逐渐增大，而Mn、TiO₂、MgO、Al₂O₃、CaO、F、SiO₂含量逐渐减小。石榴子石边部普遍发育明暗相间的振荡环带结构，且钙铁榴石在深色环带中的含量高于两侧浅色条带，钙铝榴石则相反。钙铁榴石和钙铝榴石含量的交替变化与环带中的明暗环带变化一致。石榴子石振荡环带的主量元素变化显示了石榴子石形成过程中的流体氧化环境不断增强，物理化学条件的反复变化等特征，为研究成矿热液演化过程提供了重要的矿物学证据。更多还原

【Abstract】 Huangshaping deposit is a representative skarn tungsten molybdenum polymetallic deposit in the middle section of Nanling metallogenic belt.To determine the composition and variation characteristics of garnet in skarn, the electron microprobe major elements of garnet were studied.The results show that the garnet was mainly composed of andradite and grossularite.The andradite contents increased and values of Mn, TiO₂,MgO,Al₂O₃,CaO,F and SiO₂decreased gradually from core to rim.The oscillatory zones is characteristic with bright and dark belts commonly existing in the rim of garnet, characterized by higher content of andradite and grossularite in dark and bright belts, respectively.The alternating changes of the content of calcium iron garnet and calcium aluminum garnet are consistent with the changes of the bright and dark belts.The change of major elements in garnet oscillation belt shows the continuous enhancement of fluid oxidation environment and repeated changes of physical and chemical conditions in the formation of garnet, which provides important mineralogical evidence for the study of metallogenic hydrothermal evolution.更多还原