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

该项目旨在重建和了解北德盆地海区(波罗的海、斯卡格拉克和卡特加特)以及欧洲最突出和最长的前阿尔卑斯山构造带--Tornquist带--的构造演化和相关的流体排出。Tornquist带包括Sorgenfrei-Tornquist带和Teisseyre-Tornquist带，这两个带都代表了前寒武纪波罗的海地盾向欧洲加里东-瓦里西加山脉的过渡区域。主要目标是：1)量化自旋转期以来到最近的构造变形；2)研究冰载荷诱导的构造作用；3)重新评估北德盆地的盐构造；4)勘探海底定向流体从中、古生界源岩和储集岩中逃逸出来。相关的假设是：1)反转构造持续到今天；2)随着中更新世冰期的开始，差异冰负荷引起的构造作用重新激活，继承和创造了新的断裂系统，部分地穿透了现今的海底；3)重力滑动是控制北德盆地北缘盐类变形的主要过程；4)研究区的含油气系统部分是泄漏的。这些目标将通过地球物理和地质方法实现。独特的核心数据集包括2016年收集的约2500公里(3500公里)反射地震数据，波罗的海有一个2700公里长的拖缆和8个GI-Guns作为震源。短小的初始偏移距30米首次实现了从古生代地层到海底的浅水深度无缝隙次表层成像。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，我们将恢复平衡剖面，这是解开和量化观测到的构造变形背后的机制所必需的。斯卡格拉克和卡特加特地区Tornquist带西北端的构造-地层演化将通过综合分析自己在研究探险期间收集的约1000公里的工业地震数据和3.200公里的反射地震数据来解决。我们将根据仅成像上千米的30.000公里的古老数据来解释新的地震数据。以往的地球物理和地球化学研究提供了令人信服的证据，证明流体从源岩和储集岩中从海底逸出。流体运移路径将被成像，流体和岩性将通过AVO方法和其他地震属性进行区分。我们假设我们的发现也将适用于邻近的腹地。

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.