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Little is known about the paleogeography before the formation of Rodinia. Paleomagnetic and geologic data are only definite enough to form reconstructions from the breakup of Rodinia [17] onwards. Rodinia is considered to have formed between 1.3 and 1.23 Ga and broke up again before 750 Ma. [18] Rodinia was surrounded by the superocean Mirovia.
It consisted of a series of continents attached to a central craton that forms the core of the North American Continent called Laurentia. An example of an orogeny (mountain building processes) associated with the construction of Rodinia is the Grenville orogeny located in Eastern North America.
In 1915, German meteorologist Alfred Wegener proposed the existence of a supercontinent that he called Pangaea. In 1937, South African geologist Alexander du Toit proposed that Pangaea was divided into two larger landmasses, Laurasia in the Northern Hemisphere and Gondwana in the Southern Hemisphere, separated by the Tethys Ocean.
At its beginning, all landmasses came together to form the supercontinent Pangaea, surrounded by one expansive ocean called Panthalassa. The Earth was relatively dry compared to the Carboniferous, with harsh seasons , as the climate of the interior of Pangaea was not moderated by large bodies of water.
[133]: 370 [134] Rodinia may have been preceded by Early-Middle Proterozoic continents called Nuna and Columbia. [133]: 374 [135] [136] After the break-up of Rodinia about 800 Ma, the continents may have formed another short-lived supercontinent around 550 Ma. The hypothetical supercontinent is sometimes referred to as Pannotia or Vendia.
The supercontinent Rodinia began to break up 870–845 Ma probably as a consequence of a superplume caused by mantle slab avalanches along the margins of the supercontinent. In a second episode c. 750 Ma the western half of Rodinia started to rift apart: western Kalahari and South China broke away from the western margins of Laurentia ; and by ...
The supercontinent, known as Rodinia, broke up around 750 Ma. A number of glacial periods have been identified going as far back as the Huronian epoch, roughly 2400–2100 Ma. One of the best studied is the Sturtian-Varangian glaciation, around 850–635 Ma, which may have brought glacial conditions all the way to the equator, resulting in a ...
The continents that had drifted away from Rodinia drifted together again during the Paleozoic: Gondwana, Euramerica, and Siberia/Angara collided to form the supercontinent of Pangea during the Devonian and Carboniferous periods, some 350 million years ago. Pangea was a short-lived supercontinent; it began to break apart again in the early ...