Urcontinent

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A primary continent is generally referred to as a continent that does not correspond to today's continents that have existed for around 50 million years and whose previous existence can be derived from various geological findings (cf. geo- archive ). The geoscientists, who postulate their previous existence, give these primary continents a name by means of which they can be clearly distinguished from other primary continents.

Examples

The primary continents include the supercontinent Pangea , Rodinia and Kenorland , the large southern continent Gondwana , the large northern continent Laurasia as well as the smaller Baltica ("Ur-Europe"), Laurentia ("Ur-North America"), Nena and others that have an independent existence before they merged with other major continents to form a major or supercontinent and / or emerged from the disintegration of a major or supercontinent. The underlying continental movement was described by Alfred Wegener , among others , who also named the supercontinent Pangea.

Historical

After much more specific and especially fixistischen definition of Hans Stille is a supercontinent or Ur kraton a mainland complex, which at least since " algonkischen has consolidated tectonic upheaval". Alfred Wegener, on the other hand, is credited with considering "his" Pangea as the primary continent from which all of today's continents emerged. Since plate tectonics has established itself as the dominant doctrine to explain continental movement , it has been assumed that Pangea only represents a relatively short and comparatively young phase of geological history, and that smaller and larger drifting continents must have existed before (see also →  Wilson Cycle ).

Individual evidence

  1. ↑ Rudolf Hohl (ed.): The history of the development of the earth. Brockhaus reference work geology. With an ABC of geology. 6th edition, (unchanged reprint of the 5th, revised edition). VEB FABrockhaus Verlag, Leipzig 1981, pp. 184-185, 664. ISBN 3-325-00100-9 .
  2. ↑ Helmut W. Flügel: The virtual world of Otto Ampferer and the reality of his time. Geo.Alp. Vol. 1, 2004, pp. 1-9 ( PDF ), pp. 3 f.
  3. ^ DAD Evans, ZX Li and JB Murphy: Four-dimensional context of Earth's supercontinents. Geological Society, London, Special Publications. Vol. 424, 2016, pp. 1–14, doi: 10.1144 / SP424.12