Paleogene geology and exhumation history of the Dinarides as reflected by provenance signatures of synorogenic siliciclastic sediments

同生硅质碎屑沉积物的物源特征反映了古近纪地质和迪纳里德斯的折返历史

• 批准号: 5434973
• 负责人: Professor Dr. Hilmar von Eynatten
• 金额: --
• 依托单位: Abteilung Sedimentologie und Umweltgeologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2004
• 资助国家: 德国
• 起止时间: 2003-12-31 至 2008-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5434973?language=en
• 关键词: Paleogene; geology; exhumation; history; Dinarides

This project aims at a multi-method characterization of the provenance of the Paleogene Dinaridic Flysch (DF), leading to a detailed understanding of the geodynamic setting and evolution of the DF basins and its adjacent source areas. The methods to be applied involve sandstone petrography, advanced heavy mineral analysis, whole-rock geochemistry, single-grain mineral and melt inclusion chemistry, as well as single-grain fission track and 40Ar/39Ar geochronology. The Dinarides form a central part of the entire European Alpine mountain chain between the Alps and the Hellenides and exhibit a rather complicated structure. The level of knowledge on its evolution is much lower compared to the adjacent orogenic belts. Within the Alpine chain, syntectonic sedimentation occurred mainly between late Early Cretaceous and Neogene time. A significant part of DF deposited in the time span between the two major periods of orogenic activities of Eastern Alps-Hellenides (a) Late Cretaceous (Eoalpine orogeny) and (b) the building of the present Alpine chain since Late Oligocene. This Paleogene time interval of flysch deposition coincides with the less known period of Alpine evolution. As an unusual feature, the Dinarides comprise three major flysch belts. The external belt represents the base of a foreland basin fill but the geotectonic osition of the internal flysch units during the Late Mesozoic-Teritary is still speculative. Also, the existence of one or two oceanic realms in this sector of the Alpine chain is a matter of debate. Most of the magmatic and metamorphic source rock units exhumed and eroded in the Paleogene are no more exposed today. Therefore, the application of the advanced methods of provenance analysis to the siliciclastic rocks of the DF are most promising in establishing a modern geodynamic understandig of the Dinarides.

该项目旨在对古近系Dinaridic复理石（DF）的物源进行多方法表征，从而详细了解DF盆地及其邻近源区的地球动力学背景和演化。所采用的方法包括砂岩岩相学、高级重矿物分析、全岩地球化学、单颗粒矿物和熔体包裹体化学、单颗粒裂变径迹和40 Ar/39 Ar年代学。Dinarides山脉是阿尔卑斯山和Hellenides山脉之间整个欧洲阿尔卑斯山脉的中心部分，具有相当复杂的结构。与邻近的造山带相比，对其演化的认识水平要低得多。在阿尔卑斯山脉内，同构造沉积主要发生在早白垩世晚期和新近纪之间。大部分DF沉积于东阿尔卑斯山-希腊山脉两个主要造山活动时期之间的时间跨度（a）晚白垩世（古阿尔卑斯造山带）和（B）晚渐新世以来现代阿尔卑斯山链的建立。复理石沉积的古近纪时间间隔与阿尔卑斯山演化的鲜为人知的时期相吻合。作为一个不寻常的功能，Dinarides包括三个主要复理石带。外部带代表了前陆盆地充填的基础，但晚中生代-第三纪内部复理石单元的大地构造位置仍然是推测性的。此外，在阿尔卑斯山脉的这一部分是否存在一两个海洋领域也是一个有争议的问题。在古近系中被剥蚀出露的大部分岩浆源岩和变质源岩如今已不再出露。因此，将先进的物源分析方法应用于DF硅质岩中，对于建立Dinarides的现代地球动力学认识是最有希望的。