Electromagnetic study of the Trans-European suture zone

我们提出了一个研究项目，用地球电磁方法研究波美拉尼亚/波兰跨欧洲缝合带(TESZ)中段地壳和上地幔的深部地电结构。TESZ构成了欧洲最突出的构造界线之一，将前寒武纪东欧地台和波罗的海地盾与中欧和西欧的古生代山脉带分开。各种地震学方法对其进行了广泛的研究，但对地下的电性结构知之甚少。因此，我们提出了一个实验，该实验由两个剖面组成，横跨缝合区，密集地被一系列宽带大地电磁站点占据，并从波兰的波罗的海延伸到东德的瓦里斯坎前线。我们打算通过在2D和3D中使用新的建模和反演算法来评估完整的大地电磁/磁变分数据集，包括各向异性。这项研究旨在提供对古生代沉积物的分层、波兰-北德电导率异常的几何形状的见解，特别强调作为异常传递函数的原因的沉积海槽和黑色页岩的区别、结晶基底的结构以及可能的地壳或上地幔各向异性。

We propose a research project to study the deep geo-electrical structure of the crust and upper mantle across the central segment of the Trans-European Suture Zone (TESZ) in Pomerania/Poland with geo-electromagnetic methods. The TESZ constitutes one of the most prominent tectonic boundaries in Europe and separates the Precambrian East European Platform and Baltic shield from the Paleozoic mountain belts of Central and Western Europe. It has been extensively studied by a variety of seismological methods, but little is known about the electrical structure of the subsurface. We therefore propose an experiment consisting of two profiles crossing the suture zone, densely occupied by an array of broadband magnetotelluric sites, and extending from the Baltic Sea in Poland to the Variscan Front in Eastern Germany. We intend to evaluate the full magnetotelluric/magnetovariational data set by employing new modelling and inversion algorithms in 2D and 3D, including anisotropy. The study aims at providing insights into the layering of Paleozoic sediments, the geometry of the Polish-North German conductivity anomaly, with a special emphasis on a distinction of sedimentary troughs and black shales as causes for anomalous transfer functions, structures of the crystalline basement, and a possible anisotropy in the deep crust or upper mantle.