In geology, Rodinia (from the Russian Родинa, rodina, meaning "motherland") is the name of a supercontinent, a continent which contained most or all of Earth's landmass. According to plate tectonic reconstructions, Rodinia existed between 1100 and 750 million years ago, in the Neoproterozoic era. It formed at ~1.0 Ga by accretion and collision of fragments produced by breakup of the older supercontinent, Columbia, which was assembled by global-scale 2.0-1.8 Ga collisional events .
Rodinia broke up in the Neoproterozoic and its continental fragments were re-assembled to form another supercontinent, called Pangaea 300-250 million years ago. In contrast with Pangaea, little is known yet about the exact configuration and geodynamic history of Rodinia. 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.
The extreme cooling of the global climate around 700 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 often thought to have been triggered by the breaking up of Rodinia.
The idea that a supercontinent existed in the early Neoproterozoic arose in the 1970s, when geologists mentioned that orogens of this age exist on virtually all cratons. Examples are the Grenville orogeny in North America, the Uralian orogeny in Siberia and the Dalslandian orogeny in Europe.
Since then many alternative reconstructions have been proposed for the configuration of the cratons in this supercontinent. Most of these reconstructions are based on the correlation of the orogens on different cratons. Though the configuration of the core cratons in Rodinia is now reasonably well known, recent reconstructions still differ in many details. Geologists try to decrease the uncertainties by collecting geological and paleomagnetical data.
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