Trans-European ash plumes from the largest explosive volcanic eruptions: A tephra record from the East European Plain

最大的火山喷发产生的横贯欧洲的火山灰羽流：来自东欧平原的火山灰记录

• 批准号: 429662378
• 负责人: Dr. Carl-Dieter Garbe-Schönberg
• 金额: --
• 依托单位: Russian Foundation for Basic Research
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2020
• 资助国家: 德国
• 起止时间: 2019-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/429662378?language=en
• 关键词: Trans; European; ash; plumes; largest

One of the prerequisites of predicting future giant eruptions is the understanding of sizes and recurrence times of past similar events. The size of known explosive eruptions, however, is often poorly constrained as the majority of estimates are based solely on proximal deposits and do not consider voluminous veils of distal ash. Many ash plumes were dispersed by prevailing westerly winds towards the East European plain where tephra findings are ubiquitous and often associated with archaeological layers. In spite of importance of these tephra findings for the paleovolcanological, paleoclimate and archaeological research, those have never been studied with modern analytical tools. Tephra from only one locality, a cluster of Paleolithic sites of Kostenki-Borschevo (Middle Don River, Russia), was geochemically characterized and linked to the famous ~40 ka Campanian Ignimbrite eruption (Italy). About a hundred of other tephra sites dispersed in south Russian steppe from Penza and Tambov cities in the north to the Caucasus Mountains in the south remain unidentified and undated. Most of the tephras occur in tens of meters thick loess sequences, while a few tephras were found also in caves in the course of archaeological excavations. These tephras are likely derived from Mediterranean, Carpathian, Turkish, North Iranian and Caucasian eruptions and - once geochemically analyzed - could inform about earlier unknown volcanic events, their magnitudes and compositions of parent magma. In addition, geochemically fingerprinted and dated tephra layers provide an excellent tool for precise correlation and dating of disparate paleoenvironmental and archaeological archives. We propose a collaborative regional study of visible tephra layers in south Russia, which will include field work for tephra and sediments sampling, characterization of paleogeographic and paleoenviromental conditions of tephra deposition, and subsequent geochemical analysis (EMPA, LA-ICP-MS, TIMS) and dating (Ar-Ar, U/Pb, (U-Th)/He) of the tephras. The project team includes volcanologists and geochemists from Germany and Russia who have extensive experience in cooperative tephra studies, as well as young Russian paleogeographers and geomorphologists with an expertise in paleoenvironmental research in south Russia. We believe that joint efforts will permit us to (i) decipher a long-anticipated tephra record from southern Russia, (ii) delineate distribution of tephras from different sources, and (iii) estimate the ages and magnitudes of parent eruptions. The identified tephra layers will be integrated into the European tephra framework and contribute to the integration of the Russian paleoenvironmental data into the all-European context.

预测未来巨型喷发的先决条件之一是了解过去类似事件的规模和复发时间。然而，已知爆炸性喷发的规模通常很难受到限制，因为大多数估计仅基于近端沉积物，而不考虑远端火山灰的大量覆盖物。许多火山灰羽流被盛行的西风吹向东欧平原，那里的火山灰随处可见，并且通常与考古层有关。尽管这些火山灰发现对于古火山学、古气候和考古学研究很重要，但从未用现代分析工具对这些发现进行过研究。仅来自一个地点的火山灰，即 Kostenki-Borschevo（俄罗斯中部顿河）的一组旧石器时代遗址，经过地球化学特征分析并与著名的~40 ka Campanian Ignimbrite 喷发（意大利）相关。大约一百个其他火山灰遗址分散在俄罗斯南部草原上，从北部的奔萨和坦波夫城市到南部的高加索山脉，但仍未被识别和确定日期。大部分碎屑岩产于数十米厚的黄土层序中，考古发掘过程中，在洞穴中也发现了少量碎屑岩。这些火山灰很可能源自地中海、喀尔巴阡山脉、土耳其、北伊朗和高加索的火山喷发，一旦经过地球化学分析，就可以了解早期未知的火山事件、其规模和母岩浆的成分。此外，地球化学指纹和测年的火山灰层为不同古环境和考古档案的精确关联和测年提供了极好的工具。我们提议对俄罗斯南部的可见火山灰层进行合作区域研究，其中包括火山灰和沉积物采样的现场工作、火山灰沉积的古地理和古环境条件的表征，以及随后的火山灰地球化学分析（EMPA、LA-ICP-MS、TIMS）和年代测定（Ar-Ar、U/Pb、(U-Th)/He）。项目团队包括来自德国和俄罗斯在火山灰合作研究方面拥有丰富经验的火山学家和地球化学家，以及擅长俄罗斯南部古环境研究的年轻俄罗斯古地理学家和地貌学家。我们相信，共同努力将使我们能够（i）破译俄罗斯南部期待已久的火山灰记录，（ii）描绘不同来源的火山灰分布，以及（iii）估计母体喷发的年龄和强度。已确定的火山灰层将被纳入欧洲火山灰框架，并有助于将俄罗斯古环境数据纳入全欧洲背景。