Though the configuration of the core cratons in Rodinia is now reasonably well known, recent reconstructions still differ in many details. Most of these reconstructions are based on the correlation of the orogens on different cratons. Since then, many alternative reconstructions have been proposed for the configuration of the cratons in this supercontinent. Examples are the Grenville orogeny in North America and the Dalslandian orogeny in Europe. The idea that a supercontinent existed in the early Neoproterozoic arose in the 1970s, when geologists determined that orogens of this age exist on virtually all cratons. The extreme cooling of the global climate around 717–635 million years ago (the so-called Snowball Earth of the Cryogenian period) and the rapid evolution of primitive life during the subsequent Ediacaran and Cambrian periods are thought to have been triggered by the breaking up of Rodinia or to a slowing down of tectonic processes. Paleomagnetic evidence provides some clues to the paleolatitude of individual pieces of the Earth's crust, but not to their longitude, which geologists have pieced together by comparing similar geologic features, often now widely dispersed. In contrast with Pannotia, little is known yet about the exact configuration and geodynamic history of Rodinia. Rodinia broke up in the Neoproterozoic with its continental fragments reassembled to form Pannotia 633–573 million years ago. 1.23 Ga by accretion and collision of fragments produced by breakup of an older supercontinent, Columbia, assembled by global-scale 2.0–1.8 Ga collisional events. It was renamed 'Rodinia' by McMenamin & McMenamin 1990 who also were the first to produce a reconstruction and propose a temporal framework for the supercontinent. Valentine & Moores 1970 were probably the first to recognise a Precambrian supercontinent, which they named 'Pangaea I'. Rodinia (from the Russian родина, rodina, meaning "motherland, birthplace" ) was a Neoproterozoic supercontinent that assembled 1.1–0.9 billion years ago and broke up 750–633 million years ago. Red dots indicate 1.3–1.5 Ga A-type granites.
Proposed reconstruction of Rodinia for 750 Ma, with orogenic belts of 1.1 Ga age highlighted in green.
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