Thermal evolution of an intracratonic rift: The Donbas Foldbelt (Ukraine)

克拉通内裂谷的热演化：顿巴斯褶皱带（乌克兰）

• 批准号: 13943550
• 负责人: Professorin Dr. Cornelia Spiegel
• 金额: --
• 依托单位: Fachgebiet Geodynamik der Polargebiete
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2005
• 资助国家: 德国
• 起止时间: 2004-12-31 至 2007-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/13943550?language=en
• 关键词: Thermal; evolution; intracratonic; rift; Donbas

The Ukrainian-Russian Pripyat-Dniepr-Donets basin is a large intracratonic rift structure formed during the Late Devonian. It is situated at the southern margin of the Precambrian East European Craton, adjacent to the Hercynian Tethyan belt in the Black Sea area and the Alpine Caucasus orogen. Its structural evolution is characterized by frequent changes between extensional and compressional settings, and periodically rejuvenated magmatism. The eastern part of the Pripyat-Dniepr-Donets basin - called Donbas foldbelt - is strongly folded and inverted. The exact timing of inversion is still under debate, but may have taken place during a major erosion period in the Permian, or in response to Alpine tectonics during the Late Cretaceous to Early Tertiary. The structure of the Donbas foldbelt was recently investigated by seismic reflectance and refraction in the frame of the international collaborative DOBRE project. In this study, the Donbas foldbelt is used as an example to investigate the evolution and inversion of an intracratonic rift basin. Zircon and apatite fission track analysis, as well as apatite (U-Th)/He analysis will be applied along two profiles; one follows the DOBRE seismic section across strike, transecting the major structural units of the Donbas foldbelt as well as the adjacent Ukrainian shield, the other section follows the former rift axis along strike. The thermochronologic data will be used to (i) relate the thermal evolution of the basin to the structural evolution, as revealed by the seismic profile, and (ii) to reconstruct the thermotectonic evolution with special emphasis to the Permian and Late Cretaceous/Early Tertiary tectonic activity that led to basin inversion.

乌克兰-俄罗斯普里皮亚特-第聂伯尔-顿涅茨盆地是形成于晚泥盆世的大型克拉通内裂谷构造。它位于前寒武纪东欧克拉通的南缘，毗邻黑海地区的海西特提斯带和阿尔卑斯高加索造山带。其构造演化以伸展与挤压环境的频繁转换和周期性的岩浆活动为特征。Pripyat-Dniepr-Donets盆地的东部--被称为Donbas褶皱带--是强烈褶皱和反转的。反转的确切时间仍在争论中，但可能发生在二叠纪的一个重大剥蚀期，或者发生在晚白垩世至早第三纪的阿尔卑斯山构造响应期间。东巴斯褶皱带的结构最近在国际合作的Dobre项目的框架内用地震反射和折射进行了研究。本文以顿巴斯褶皱带为例，研究了克拉通内裂谷盆地的演化和反转。将沿两条剖面进行锆石和磷灰石裂变径迹分析以及磷灰石(U-Th)/He分析；一条剖面沿多布雷地震剖面穿过走向，横穿顿巴斯褶皱带的主要构造单元以及邻近的乌克兰盾；另一段沿走向沿前裂谷轴线穿过。热年代学资料将被用来(I)将盆地的热演化与地震剖面所揭示的构造演化联系起来，(Ii)重建热构造演化，特别是二叠纪和晚白垩世/早第三纪导致盆地反转的构造活动。