脉型和斑岩型钼铜矿化的成因关系：以内蒙东部白土营子矿田为例

In several Mo (Cu) ore-fields, the quartz vein-type Mo (Cu) mineralization shows a close spatial association with porphyry Mo (Cu) mineralization (either at shallow levels or peripheral areas), but their genetic links are ambiguous. The Baituyingzi ore-field, eastern Inner Mogonia, contains vein-type and porphyry Mo (Cu) mineralization that were almost coeval, making it an excellent case for studying the above-mentioned issue. In this program, high-resolution in-suit Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) trace element mapping of ore minerals (i.e., pyrite, chalcopyrite, molybdenite) was coupled with electron probe microanalysis, microthermometry and composition of fluids, and O–H isotopic analysis, to precisely clarify the genetic relationship between these two different styles of deposits in Baituyingzi ore-field, and to provide valuable information for rebuilding the evolutional history of the Baituyingzi hydrothermal metallogenic system. This program would not only provide valuable guidance for the future exploration work of similar type ore deposits, but also has significant scientific significances on the delicate research on complex polymetallic metallogenic systems.

许多钼铜矿田中石英脉型钼铜矿与斑岩矿床共存，但两者的成因关系尚不明确。本项目拟借助渐趋成熟的高精度原位微区分析技术（LA-ICPMS），针对内蒙东部白土营子矿田中石英脉型和斑岩型钼铜矿床的硫化物（黄铁矿、辉钼矿、黄铜矿）开展原位微区扫面，结合电子探针分析、流体包裹体显微测温及成分分析、石英O-H同位素研究，精确厘定白土营子矿田两种矿化类型的成因关系，并为重塑该热液成矿系统及其演化过程提供更多的信息。该研究不仅对同类矿床的深入勘查工作有重要的借鉴意义，还对拓展多金属复杂成矿系统的精细化研究具有重要的科学意义。

许多钼铜矿田中石英脉型钼铜矿与斑岩矿床共存，但两者的成因关系尚不明确。本项目通过对内蒙东部白土营子矿田中石英脉型（库里吐、白马石沟）和斑岩型（白土营子）钼铜矿床不同热液阶段的硫化物（黄铁矿、辉钼矿、黄铜矿）开展LA-ICP-MS原位微区分析，结合电子探针分析、流体包裹体显微测温及成分分析、石英O-H同位素、以及前期年代学研究成果，明确建立了脉型和斑岩型钼铜矿的成因联系。认为两者构成同一早三叠世同碰撞环境钼成矿系统独立的热液活动中心，同一系统形成不同产状和Cu/Mo比值的两类矿床可能源于应力条件（如区域构造和局部流体压力）、围岩组成（如岩体暗色矿物含量）、流体性质（如盐度）等的差异，该研究成果不仅丰富了斑岩系统地质模型，对同类矿床的勘查工作有重要的借鉴意义。此外，通过深化前期研究，识别了同碰撞环境白土营子成矿系统钼成矿花岗斑岩的鉴别标志及形成机制，如相对富水和高演化性，与岩浆源区早期受不均一流体交代有关。