Alpine Valley Formation and Rock Wall Retreat Over Neogene, Quaternary and Holocene Time Scales
摘要
This chapter discusses valley formation in the German Northern Calcareous Alps on a conceptual level and then on a Neogene, Quaternary, Lateglacial and Holocene time scale. In the Neogene up to the early Pliocene geomorphological processes mostly under tropical to subtropical climatic conditions led to the development of the initial fluvial network and formed the initial shape of the mountains. Global cooling initiated a cycle of glacials and interglacials in the Quaternary, caused the origin of massively incised trough valley systems, and finally left the valleys with a thick sediment cover. Erosion and sediment redistribution altered completely the appearance of the valleys in the Lateglacial and the Holocene. Valley-shaping processes and related landforms include rockfall and talus production, debris flows and fan evolution, rock-slope failures, landslides and dammed valleys, as well as fluvial incision and gorge evolution. High ongoing level of geomorphological activity is highlighted in a number of examples from the German Alps and immediately neighbouring parts of the Northern Calcareous Alps.