European rivers evolution project (EREP)
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Introduction
Europe is a unified geographical region that has undergone a broadly consistent geological and climatic history over the past few million years. Today the region lies in the temperate climatic and vegetational zone but during the recent past it has been subjected to climatic change that has given rise to long periods of periglacial and even glacial conditions. In coastal areas, sea-level change, largely driven by glacial eustasy, has caused intermittent regressions and transgressions; in and adjacent to glaciated regions, isostatic and forebulge effects have also caused major land- and sea-level variations. All these variations are superimposed on longer-term trends in climate and tectonic evolution of the continent.The drainage system of Europe has evolved in response to the development of the continent during the late Cenozoic. The position of the region at the margin of the Eurasian continent has been crucial in determining the events that have influenced its geological evolution. By their nature, rivers owe their existence to, and are strongly influenced by, tectonic activity and climatic variability. The interplay of these two major factors is responsible for determining the form of the modern river system, which should be considered as the product of continual remodelling.
Because river valleys are major zones of terrestrial deposition, an understanding of their detailed geological record provides a calibration of the geological evolution of the North Atlantic region as a whole throughout the past three million years. In addition, the intercalation of marine or estuarine sediments in the river sequences allows correlation with the offshore and potentially with the deep-sea facies. As will be shown below, there is considerable evidence of palaeoclimatic significance in river-sediment sequences; from this evidence it is clear that the European rivers have functioned as an integrated system.
A series of maps of the important European rivers will be produced. These rivers have been selected because their individual histories illustrate the impact and interplay of the major influencing factors. They also provide important transects across the continent from west to east and north to south, i.e. from zones of maximum impact of glaciation, particularly during the Middle and Upper Pleistocene, to zones which were never glaciated, and from maritime to continental climate-dominated regimes.
In order to appreciate the evolution of the European drainage system it is vital to adopt a uniform stratigraphical timetable. The Netherlands' Neogene stratigraphical terminology will be ataken as the norm, in which the Plio-Pleistocene boundary is placed at the base of the Praetiglian Stage (c. 2.6 Ma BP). This widely applicable boundary is thought to be 'natural' in Europe because it marks the first arrival of true cold climates. It has also been used extensively throughout the region in stratigraphical schemes.
Links:
Protocol for mapping fluvial courses
Participants
Budapest meeting April 2005 report
Ukraine rivers - A.Matoshko