The marine sector of the North German Basin and the Tornquist Zone: Structural evolution and fluid flow

该项目旨在重建和理解北德意志盆地海相（波罗的海、斯卡格拉克和卡特加特）和欧洲最突出、最长的前高山构造线——Tornquist带的构造演化和相关的流体排出。Tornquist带包括Sorgenfrei-Tornquist带和teissere -Tornquist带，它们都代表了前寒武纪波罗的海地盾到加里东-瓦里斯坎欧洲的过渡区域。主要目标是：1)量化自Rotliegend至今的结构变形；2)研究冰荷载诱发的构造运动；3)北德意志盆地盐构造重新评价；4)寻找中、古生界烃源岩和储层的海底定向流体逸出。相关假设有：1)构造反转持续至今；2)随着中更新世冰期的开始，不同冰荷载引起的构造运动重新激活了原有的断裂系统，并形成了新的断裂系统，部分刺穿了现今的海底；3)重力滑动是控制北德意志盆地北缘盐变形的主导过程；4)研究区含油气系统存在部分泄漏。这些目标将通过地球物理和地质方法来实现。独特的核心数据集包括2016年在波罗的海收集的约2500公里（3500公里）的反射地震数据，其中有2700公里长的拖缆和8个gi - gun作为地震源。30米的短初始偏移量首次允许从古生代地层到海底的无间隙地下成像，尽管水深较浅。将创建具有无与伦比分辨率的深度剖面，使我们能够进行准确的断层滑动分析。在此基础上，我们将恢复平衡部分，这对于揭示和量化观察到的结构变形背后的机制是必要的。对斯卡格拉克和卡特加特地区Tornquist带西北端的构造地层演化，将通过对自己研究考察期间收集的约1000公里工业和3200公里反射地震数据的综合分析来解决。我们将在仅对上方千米进行成像的30万公里古数据的背景下解释新的地震数据。以前的地球物理和地球化学研究提供了令人信服的证据，证明流体在海底从源岩和储集岩中逸出。流体运移路径将被成像，流体和岩性属性将通过avo方法和其他地震属性来区分。我们假设我们的研究结果也适用于邻近的腹地。

This project aims at reconstructing and understanding the structural evolution and related fluid expulsion in the marine sector (Baltic, Skagerrak and Kattegat) of the North German Basin and the most prominent and longest pre-Alpine tectonic lineament of Europe, the Tornquist Zone. The Tornquist Zone includes the Sorgenfrei-Tornquist and the Teisseyre-Tornquist Zones, both representing the transition area from the Precambrian Baltic Shield to the Caledonian-Variscan Europe.The major objectives are: 1) quantifying structural deformation since the Rotliegend to recent; 2) investigating ice-load induced tectonism; 3) re-assessing salt tectonics in the North German Basin; and 4) exploring sea floor directed fluid escape from Mesozoic and Paleozoic source and reservoir rocks.The related hypotheses are: 1) inversion tectonics lasts until today; 2) with the onset of glacial periods in the middle Pleistocene differential ice load induced tectonism reactivated inherited and created new fault systems, which partly pierce the present day seafloor; 3) gravity gliding was the dominant process that controlled salt deformation along the northern margin of the North German Basin; 4) that the petroleum system in the study area is partly leaky. The goals will be achieved by geophysical and geological methods. The unique core data set comprises ca. 2500 (out of 3500) km of reflection seismic data collected in 2016 with a 2700 km long streamer and eight GI-Guns as seismic source in the Baltic Sea. The short initial offset of 30 m allows for the very first time and in spite of the shallow water depth gapless subsurface imaging from Paleozoic strata up to the seafloor. Depth section with yet unparalleled resolution will be created, enabling us for an accurate fault slip analysis. Based on that we will restore balanced sections, which is necessary to unravel and quantify the mechanisms behind observed structural deformation. The tectono-stratigraphic evolution of the north-western end of the Tornquist Zone in the Skagerrak and Kattegat will be addressed by the integrated analyses of both ca. 1000 km of industrial and 3.200 km reflection seismic data collected during own research expeditions.We will interpret the new seismic data in the context of > 30.000 km of vintage data that image the upper kilometer only. Previous geophysical and geochemical studies provided compelling evidence that fluids escape on the seafloor origin from source and reservoir rocks. Fluid migration paths will be imaged and fluid and lithology properties will be distinguished by AVO-methods and other seismic attributes. We assume that our findings will be applicable also for the adjacent hinterland.