Neotectonics of The Netherlands: a review

Abstract

Earthquakes and vertical land movements inferred from geodetic levelling results demonstrate that the Netherlands is situated on a tectonically active part of the Earth's surface. Tectonic subsidence analyses of the sedimentary records in the basins and the history of tectonic uplift inferred from Meuse river terraces show that the current tectonic activity is part of a deformation phase which began in the late Early Miocene, which we take as the start of the neotectonic period. The neotectonic faulting mode is normal-slip. This is in accordance with the present-day orientation of the maximum horizontal stress, and the vertical orientation of the maximum stress. However, the neotectonic fault zones are reactivated Variscan or older wrench faults. These faults have been reactivated repeatedly during the Mesozoic and Cenozoic in normal and wrenching modes, and therefore represent fundamental crustal weakness zones. As a result, the surficial neotectonic fault pattern resembles the inherited wrenching fault pattern, although the faulting mode is normal-slip. This is illustrated for the area where normal faults have displaced the Meuse fluvial terrace system in the southeastern part of the Netherlands. The neotectonic vertical motions in and around the Roer Valley Rift System have affected the courses of the Rhine and Meuse rivers from Pliocene times until the present. In addition, a fluvial terrace staircase developed along the Meuse river in response to the uplift of the Ardennes-Rhenish Massif and its foreland, for example near Maastricht. Furthermore, small fault scarps are present along segments of the bounding fault zones of the Roer Valley Graben: the Peel Boundary Fault Zone and the Feldbiss Fault Zone. In other parts of the Netherlands the neotectonic vertical motions have no direct expression in the morphology. Examples of possible indirect control on the morphology in these areas occur in glacial landscapes, the Zuiderzee Basin and the coastal zone.