from Wikipedia, the free encyclopedia
Avalonia Basement in Europe.

Avalonia is the name of a small continent in geological history that broke off from the northern edge of the southern continent of Gondwana in the Lower Ordovician and collided with Baltica in the Upper Ordovician . Today it forms the foundation of northern Germany, the southern North Sea, Central England, Wales, southern Ireland and smaller parts of North America (Newfoundland, Nova Scotia, New Brunswick, parts of the New England states and the northern part of Florida). The parts of Avalonia today, European, are also referred to as Eastern Avalonia, while the North American parts are also known as West Avalonia. They have also been viewed by some authors as two independent terranes.


The name was apparently first used by a group of authors around Christopher Scotese , Richard Bambach and Rob Van der Voo in 1979. Avalonia is named after the Avalon Peninsula in what is now Newfoundland . However, the area was recognized earlier as a separate structural tectonic unit of the Appalachians and referred to as the Avalon Platform or later the Avalon Zone. In the early 1980s, the term Avalon-Terrane was often used in the literature for Avalonia .

History of the small continent

Schematic representation of the paleogeographic development of Avalonia, Baltica and Laurentia from the Ordovician to the Devonian.

In the Young Proterozoic and Old Paleozoic (approx. 700-480 million years) Avalonia was in front of the northern (present-day) South America and northern part of West Africa, and thus part of the supercontinent Gondwana , which is located in the southern hemisphere and positioned around the South Pole . These peripheral parts of Gondwana were recorded in the late Proterozoic by the Cadomian orogeny (650-550 ma).

In the Lower Ordovician , Avalonia broke off at higher southern latitudes from Gondwana and drifted in the direction of the equator towards Baltica and Laurentia . The Rhine Ocean opened up between Avalonia and Gondwana . To the north of Avalonia, under the western part of the Iapetus, under the eastern part of Avalonia, the Tornquist Ocean was subducted. In the low southern latitudes Avalonia collided with Baltica (today's Northern and Eastern Europe) in the upper Ordovician . The Tornquist Ocean between Baltica and Avalonia was closed. The dividing line (" suture ") is called the Tornquist line . In the Silurian, the now connected Baltica and Avalonia collided with Laurentia (today's North America with Greenland, northern Ireland and Scotland), closing the Iapetus Ocean . The new major continent resulting from Baltica, Laurentia and Avalonia is called Laurussia .

Opening of what is now the North Atlantic

The opening of the North Atlantic from south to north in the Mesozoic and Cenozoic meant that parts of the former small continent Avalonia are now located in northern Central Europe and eastern North America ( Newfoundland , New England states).


In the ARD television film "Play" from 2019, "Avalonia" refers to a virtual reality computer game that first becomes the elixir of life and later an addiction for the leading actress Jennifer.

Individual evidence

  1. ^ H. Williams: The Appalachians in northeastern Newfoundland - A two-sided symmetrical system. American Journal of Science, 262; 1137-1158, New Haven 1964 ISSN  0002-9599
  2. Video: Play , ard.de.


Web links