山西大同钾镁煌斑岩是华北克拉通上目前发现的唯一一处钾镁煌斑岩，前人曾在金刚石找矿过程中对其含矿性开展过研究，然而其精确的年代，系统的地球化学，特别是同位素地球化学工作仍属空白，这严重制约了对其成因的了解。本项目拟选择该钾镁煌斑岩为研究对象，通过详细的年代学、系统的地球化学，包括Sr-Nd-Pb-Hf-Os-Mg等同位素，以及稀有气体同位素示踪研究，确定该区钾镁煌斑岩的活动时代，揭示其地幔源区的地球化学特征和物质组成，确定岩石成因、地幔演化过程以及岩浆的起源深度。揭示陆壳物质重循环进入地幔源区的时间尺度（什么时候）和空间尺度（陆壳物质能进入地幔多深），从地幔演化角度为华北克拉通早期演化过程中的古俯冲地质事件提供地球化学证据。

The lamproite outcropped in Datong, Shanxi province is the only lamproite that has ever been found on the North China Craton. Previous studies mainly focused on their mineralogy and potential for diamond deposit. No detailed high precision geochronologic, and systematic isotopic data are available to date, which seriously hindered our understanding of its petrogenesis and geodynamic processes. In this project, we 'll perform high precision geochronology, and multi-isotopic (Sr-Nd-Pb-Hf-Os-Mg) studies, along with noble gas isotopic tracing to constrain its mantle source characteristics, petrogeneisis, and source lithology, to reveal when and how the crustal materials were recycled back into the mantle through subduction. This study will, from a geochemical view probably provide evidence for the Paleo-subduction events during the early evolution era of the North China craton.