The Quaternary as a System is traditionally considered to be the Ice Age - an interval of oscillating climate extremes (glacials and interglacials) encompassing the Pleistocene and the Holo-cene as Series. The term was formally introduced by Desnoyers (1829). The basic principles used in subdividing the Quaternary into chronostratigraphic units are the same as for other Phaner-ozoic units which require boundary definitions and the designation of boundary stratotypes (Salvador 1994). However, in contrast to the rest of the Phanerozoic, the division of Quaternary sequences on the basis of climatic changes documented in the sedimentary record is fundamental and has a long tradition. Classifications based on climatostratigraphic units such as ‘glacials’ or ‘interglacials’ are reasonably well-established in different countries or areas of Central Europe, and are accepted as regional chronostratigraphic standards (Gibbard & West 2000; Gibbard & Kolfschoten 2004; Litt et al. 2005).
The climatostratigraphic terms ‘interglacial’ and ‘interstadial’ were first defined by Jessen & Milthers (1928) for periods with characteristic records of non-glacial climate, as indicated by palaeobotanical evidence for major vegetation changes. Following these suggestions, interglacials in Central Europe are classified as temperate periods with a climate optimum at least as strong as the present interglacial (Holocene) in the same region. Interstadials are assumed to have been either too short or too cold to reach the climate level of interglacial type in the same region.
In North America, the fundamental units of geological-climate classification have been defined as follows (American Commission on Stratigraphic Nomenclature 1961): ‘A glaciation is a climatic episode during which extensive glaciers developed, attained a maximum extent, and receded. A stadial is a climatic episode, representing a subdivision of a glaciation, during which a secondary advance of glaciers took place. An interstadial is a climatic episode within a glaciation during which a secondary recession or standstill of glaciers took place. An interglacial is an episode during which the climate was incompatible with the wide extent of glaciers that characterize a glaciation’ (see also Gibbard & Kolfschoten 2004). The glacially based terms, however, are very difficult to apply in regions which were not directly affected by ice activity. Furthermore, cold rather than glacial climates have often tended to characterize the periods between interglacial events. Therefore, the term ‘cold stage’ has been adopted instead of ‘glacial’ or ‘glaciation’ (Gibbard & West 2000).
The status of the Quaternary, long regarded as a geological period, has recently been questioned as a formal stratigraphic unit, with proposals for its abandonment or modification (Grad-stein et al. 2004; Pillans 2004; Steininger 2002). Gibbard et al. (2005), however, argue that the Quaternary should be retained as a formal period of geological time following the Neogene which would be formally subdivided into the Pleistocene and Holocene epochs (see also Bowen & Gibbard 2006). A formal decision on its chronostratigraphic status is pending.
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This two-volume set provides the first comprehensive account in English of the geology of Central Europe. Written by more than 200 scientists from universities and research centres spread across Europe and North America, the 21 chapters are based on the main stratigraphic periods. Individual chapters outline the evolution of the region divided into a variety of sections which include overviews of the stratigraphic framework, climate, sea-level variations, palaeogeography and magmatic activity. These are followed by more detailed descriptions of the Central European succession, covering the main basins and magmatic provinces. Each chapter is thoroughly referenced, providing a unique and valuable information source.
Volume 1 focuses on the evolution of Central Europe from the Precambrian to the Permian, a dynamic period which traces the formation of Central Europe from a series of microcontinents that separated from Gondwana through to the creation of Pangaea. Separate summary chapters on the Cadomian, Caledonian and Variscan orogenic events as well as on Palaeozoic magmatism provide an overview of the tectonic and magmatic evolution of the region. These descriptions sometimes extend beyond the borders of Central Europe to take in the Scottish and Irish Caledonides as well as the Palaeozoic successions in the Baltic region.
Volume 2 provides an overview of the Mesozoic and Cenozoic evolution of Central Europe. This period commenced with the destruction of Pangaea and ended with the formation of the Alps and Carpathians and the subsequent Ice Ages. Separate summary chapters on the Permian to Cretaceous tectonics and the Alpine evolution are also included. The final chapter provides an overview of the fossil fuels, ore and industrial minerals in the region.
The Geology of Central Europe is a key reference work suitable not only for libraries across the world, but of interest to all researchers, teachers and students of European Geology.