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Автор: M. R. House, A. S. Gale
Издательство: Geological Society Publishing House
Год издания: 1995
isbn: 1897799233
Количество страниц: 204
Язык: english
Формат: PDF
Размер: 11,1 Мб
Каталожный номер: 30218
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The metronomic variations of the Earth-Moon system and of theEarth-Sun orbital patterns produce gravitational and temperatureeffects that alter the physical environment on the Earth’ssurface. These give an interpenetrating effect of forcing cyclesranging from twice-daily tides, day-night alternations, varioustidal patterns and the annual solar pattern. All of these havebeen used palaeontologically to give precision to short-termage determination in the past. It is cycles of the Milankovitch band that are showing promiseof enabling new practical timescales to be established for partsof the geological record. These depend on changes in the Earth-Sundistance and changes in the tilt of the Earth’s axis withrespect to the Earth’s orbit round the Sun. There is increasingevidence that small-scale sedimentary rhythmic couplets mayrepresent the effect of such changes. The disentangling of theinterpenetrating cycles to produce an orbital forcing timescaleis an exciting problem and challenge for palaeobiology and sedimentology.These should enable numerical dates to be given to bio- andchronostratigraphical timescales and eventually enable manyEarth processes to be analysed in real time. The papers in this volume represent major new developments insedimentological, paIaeontological, geochemical and stratigraphicalresearch being undertaken in this field.
Ключевые теги: космос, астрономия |
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