当前位置: X-MOL 学术Aeolian Res. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Geochemical signature of sources, recycling and weathering in the Last Glacial loess from the Rhône Valley (southeast France) and comparison with other European regions
Aeolian Research ( IF 3.1 ) Pub Date : 2019-11-28 , DOI: 10.1016/j.aeolia.2019.100561
Mathieu Bosq , Pascal Bertran , Jean-Philippe Degeai , Alain Queffelec , Olivier Moine

Pleistocene loess of the Rhône Valley and Provence region, disconnected from the two main European aeolian systems (North European Loess Belt and Danube basin), are of interest to test the impact of source variability, grain size sorting, weathering and sediment recycling on the geochemical composition. The concentration of major, trace and rare earth elements in loess and potential sources was analysed through Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) and ICP-Mass Spectometry (ICP-MS). Analyses show a genetic relationship between loess and the Ca-rich river sediments from the Alpine Ice Sheet (AIS). The loess of Provence show distinctive properties with a higher CaO and MgO content and a higher Europium anomaly (Eu/Eu*), suggesting sources richer in dolomite together with a contribution from mafic rocks (Alpine ophiolite complex). The homogeneous loess composition, compared to alluvial sources, reflects particle mixing during transport in the atmosphere. At the European scale, the geochemical composition of loess changes according to regions, but remains consistent within each region. Such variability is mostly related to the composition of rocks outcropping in respective catchments and especially in areas covered by ice sheets. The Chemical Proxy of Alteration (CPA) and Rb/K ratio suggest a weak chemical weathering linked to the cold and dry conditions typical of the Last Glacial. Recycling of older aeolian formations possibly caused loess enrichment in resistant minerals and quartz, especially for loess derived mostly from the abrasion of aeolian sand (Aquitaine).



中文翻译:

来自罗纳河谷(法国东南部)的最后冰川黄土的来源,回收利用和风化的地球化学特征,并与其他欧洲地区进行比较

罗纳河谷和普罗旺斯地区的更新世黄土与欧洲两个主要的风成系统(北欧黄土带和多瑙河盆地)断开了连接,对测试震源变化,粒度分类,风化和沉积物回收对地球化学的影响很感兴趣。组成。通过电感耦合等离子体原子发射光谱法(ICP-AES)和ICP-MS质谱法(ICP-MS)分析了黄土和潜在来源中主要,痕量和稀土元素的浓度。分析表明,黄土与来自高山冰原(AIS)的富含钙的河沉积物之间存在遗传关系。普罗旺斯的黄土具有独特的性质,具有较高的CaO和MgO含量以及较高的Euro异常(Eu / Eu *),暗示了富含白云岩的来源以及镁铁质岩石(高山蛇绿岩复合体)的贡献。与冲积源相比,均匀的黄土成分反映了大气中运输过程中的颗粒混合。在欧洲范围内,黄土的地球化学组成随区域而变化,但在每个区域内保持一致。这种变化主要与各个流域特别是冰盖覆盖区域露头的岩石组成有关。化学变化指标(CPA)和Rb / K比值表明化学风化作用较弱,这与上个冰川时期的寒冷和干燥条件有关。回收较老的风成岩可能会导致黄土富集抗矿物质和石英,

更新日期:2019-11-28
down
wechat
bug