Stratigraphic Landscape Analysis and geomorphological paradigms: Scandinavia as an example of Phanerozoic uplift and subsidence
Stratigraphic Landscape Analysis (SLA) is based on a) the relationship between peneplains (low-relief denudation surfaces) in basement and their cover rocks of different age, b) the crosscutting relationships between such re-exposed peneplains and never covered (epigene) peneplains, and c) the occurrence of valleys incised below peneplains. Previous studies based on detailed SLA of the South Swedish Dome (SSD) have identified two major re-exposed peneplains, the flat sub-Cambrian peneplain and the sub-Jurassic/Cretaceous peneplain with undulating hilly relief. Both surfaces developed close to former sea levels, were subsequently transgressed, and buried below sedimentary covers. The preservation of these peneplains documents that uplift of the land surface was followed by subsidence. Crosscutting relationships between these re-exposed and tilted peneplains and a third peneplain, an epigene and horizontal plain with residual hills, demonstrate that the latter is younger and thus of post-Cretaceous age. Three topographic highs characterize Scandinavia, the Northern Scandes (NS), the Southern Scandes (SS), and the low SSD. We show that the three relief types of the SSD can be identified across Scandinavia and that they demonstrate phases of uplift/denudation and subsidence/burial of Scandinavia during the Phanerozoic. In particular, we show that the epigene peneplains of the NS, the SS and the SSD are Cenozoic erosion surfaces and this also leads us to identify three major Cenozoic morphotectonic units. A result of our studies is that the paradigm of continuous uplift of steady state landscapes cannot be assumed as a universal model of landform evolution.