Der tektonische Bau des NW-Teils der Selke-Decke am nördlichen Harzrand

Abstract

KÖNIG. .; SCHWAB, M.: Tectonic Structure of the north-western part of the elke nappe at the northern margin of the Harz Mountains. - Hercynia N.F. 34: 129- 159. The Selke nappe is situated at the northern margin of the Harz Mountains, which is the tectonic border between the Variscan basement and the Triassic-Mesozoic sequence of the subhercynian region. The allochthonous Upper Devonian volcano- sedimentary secquence of about 800 m overlays the parautochthonous Lower Carboniferous rock of the Harzgerode Zone. A new mapping of the area and detailed tectonic examination in the quarry Rieder near Ballenstedt were the basis for a reconstruction of the structural processes that occur at the northwestern part of the Selke nappe. Three factors are responsible for the complex character of the structural cond- itions of the rocks : the nappe tectonics caused by the deposition of the Selke nappe; the northward overthrusting of the Palaeozoic Harz block over the Mesozoic sediments along the northern Harz boundary; and the rotation of single segment of Palaeozoic rock at wrench- fault upthrusting segments , the so called "Sporne". There was no indication for a common deformation between the Palaeozoic and the steeply dipping Cretaceous sandstones of the "Teufelsmauer" which were erected and overturned during the Santonian uplift.