Pleistocene Deposits of the Swiss Northern Alpine Foreland: Stratigraphic Concept and Nomenclature

Abstract

The stratigraphic scheme for the Pleistocene deposits in the Northern Alpine Foreland, as defined in southern Germany, cannot be directly adopted in northern Switzerland due to a fundamental difference between the mechanisms that control the regional morphogenesis. Therefore, an independent concept for the stratigraphic procedure, nomenclature, and hierarchical structure was developed for the Swiss Pleistocene deposits, based on mapping units (at the rank of formations, even if informal in most cases) defined and named according to lithostratigraphic guidelines (and geomorphological criteria in some cases). These basic “building blocks” also provide the flexibility that is needed in case knowledge of the number, extent, and hierarchy of glacier advances into the Swiss Northern Alpine Foreland changes as a result of new research, as has been the case a number of times during the past 20 years. The mapping units are grouped into hierarchically superior units that are based on a genetic interpretation (advance, glaciation, and glacial). Despite some deviation from lithostratigraphic rules, we consider this to be a reasonable approach. The stratigraphic concept presented here has been successfully applied in the map sheets of the 1:25,000-scale Geological Atlas of Switzerland; furthermore, it provides a robust framework for absolute age determinations.