Spatial and temporal variations in mantle redox state beneath the Massif Central, France

法国中央地块的第三纪和第四纪火山活动在大范围内以橄榄岩捕虏体的形式采集了次大陆岩石圈地幔（SCLM）样品。Escherir等人（2000年）和Downes等人（2003年）的地球化学研究表明，存在两个不同的地幔域，分别位于北纬45 ° 30 '和南纬45° 30'。这里的目标是跟踪地幔氧化还原状态的变化，这将提供进一步的线索SCLM在欧洲的这一部分的演变，例如，如果这两个域记录不同的氧化还原状态。除了空间上的变化外，还可以通过分析不同喷发年龄（~20 Ma至最近）的火山中心的捕虏体来研究时间上的变化。还将监测交代作用的影响，因为经常观察到这种相互作用改变氧化还原状态。这项研究将为西欧地下SCLM的化学演化提供重要的新信息。

The Tertiary and Quaternary volcanism of the Massif Central, France, has sampled the subcontinental lithospheric mantle (SCLM) in the form of peridotite xenoliths over a large geographical area. Geochemical studies by Lenoir et al. (2000) and Downes et al. (2003) suggest the existence of two distinct mantle domains, lying north and south of 45° 30’ latitude, respectively. The goal here is to trace the variations in mantle redox state that will provide further clues about the evolution of the SCLM in this part of Europe, for example if these two domains record distinctive redox states. In addition to spatial variations, temporal changes can be studied by analysing xenoliths from volcanic centers with different eruption ages (~20 Ma to recent). The effects of metasomatism will also be monitored since such interactions are often observed to modify redox state. This study will provide important new information on the chemical evolution of the SCLM beneath Western Europe.