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It is very unlikely that Rodinia was the first supercontinent. However, it was certainly the first global supercontinent - incorporating essentially all of the Earth's continents - about which we have solid information. Rodinia formed perhaps as early as 1200 Mya. Most of its mass was probably located in the low latitudes of the Northern Hemisphere. However, the actual arrangement of cratons is still being debated. (North America) seems to have been the hub of Rodinia. At the time, Laurentia was rotated about 90° clockwise with respect to its present orientation, so that Greenland was on the East side. (northern and eastern Europe) and Siberia lay off to the southeast. and had not yet formed, but various bits and pieces were spread out in a long arc on the west side. and were probably to the north or northwest. The position of other cratons is even less well known.
Rodinia was ripped apart during the Early Neoproterozoic () by the Grenville Orogony, which left enormous amounts of volcanic rock on many of today's continents. Rodinia was surrounded by a single ocean, called the or Sea. Towards the end of the Proterozoic, this supercontinent fragmented, giving rise to the late continents of , , and . From Pannotia in turn came the diverse continents of , , and .
page uploaded 5 April 2002 MAK
last revised ATW051228
checked ATW050822
unless otherwise specified, text © M. Alan Kazlev 2002
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