Some of the oldest rocks on earth have been found in the African Cratonic Basement rocks of ages in excess of 2 billion years.
12.
Continental lithosphere is typically ~ 200 km thick, though this varies considerably between basins, mountain ranges, and stable cratonic interiors of continents.
13.
The host rocks for the intrusions are middle Proterozoic granites and gneiss and the complex was associated with the Cambrian rifting of the cratonic rocks.
14.
Ur can, nevertheless, be half a billion years younger than Vaalbara, but the concepts of these two early cratonic assemblages are incompatible.
15.
Attempts to identify equivalent cratonic sequences on other continents have met with only limited success, suggesting that eustasy is unlikely to be the sole responsible mechanism.
16.
It marks the progressive submergence of this landmass by a shallow cratonic sea and its burial by shallow marine sediments of the Cambrian-Early Ordovician Sauk sequence.
17.
Mantle tomography shows that cratons are underlain by anomalously cold mantle corresponding to lithosphere more than twice the typical thickness of mature oceanic or non-cratonic, continental lithosphere.
18.
Several plate tectonic reconstructions propose an Archean-Paleoproterozoic connection between the cratonic core of North America, the continent Laurentia, and that of Siberia, the continent paleomagnetic evidence.
19.
Some microcontinents are fragments of Gondwana or other ancient cratonic continents : Newfoundland for example are within the continental shelves of their adjacent continents, separated from the mainland by inland seas flooding its margins.
20.
The synchroneity and extent of the Tokwe Segment is considered strong evidence supporting a predominantly intra-cratonic origin for the Late Archaean greenstone belts of Zimbabwe and refuting an arc accretion origin for the craton.
