Tunnel valleys are assumed to form near the margin of ice sheets. Hence, they can be used to reconstruct the dynamics of former ice margins. The detailed formation and infill of tunnel valleys, however, are still not well understood. Here, we present a dense grid of high‐resolution 2D multi‐channel reflection seismic data from the German sector of the southeastern North Sea imaging tunnel valleys in very great detail. Three tunnel valley systems were traced over distances ranging between 11 and 21 km. All tunnel valleys are completely filled and buried. They differ in incision depth, incision width and number of incisions. The tunnel valleys cut 130–380 m deep into Neogene, Palaeogene and Cretaceous sediments; they show a lower V‐shaped and an upper U‐shaped morphology. For individual tunnel valleys, the overall incision direction ranges from east–west to northeast–southwest. Two tunnel valleys intersect at an oblique angle without reuse of the thalweg. These valleys incise into a pre‐existing glaciotectonic complex consisting of thrust sheets in the northwest of the study area. The analysis of the glaciotectonic complex and the tunnel valleys leads us to assume that we identified several marginal positions of (pre‐)Elsterian ice lobes in the southeastern North Sea.

中文翻译：

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北海东南部隧道山谷的建筑：高分辨率地震成像的新见解

假定隧道谷在冰盖边缘附近形成。因此，它们可用于重建以前冰缘的动力学。然而，对隧道谷的详细形成和填充仍不十分了解。在这里，我们非常详细地介绍了密集的网格，该网格由来自北海东南部成像隧道山谷德国段的高分辨率二维多通道反射地震数据组成。在11至21 km的距离范围内追踪了三个隧道山谷系统。所有隧道谷都被完全填埋。它们在切口深度，切口宽度和切口数量上有所不同。隧道河谷切入新近纪，古近纪和白垩纪沉积物的深度为130-380 m。它们显示出较低的V形和较高的U形形态。对于单个隧道谷，整体切口方向从东西向到东北西南。两个隧道谷以倾斜角度相交，而没有重新使用海藻。这些山谷在研究区的西北切成早先的冰川构造复合体，由冲断片组成。对冰川构造复合体和隧道谷的分析使我们假设，我们在北海东南部确定了（前）埃尔斯特冰裂的几个边缘位置。