Neoproterozoic
Speech parts
1. Neoproterozoic - Adjective
2. Neoproterozoic - Proper noun
Meaning
Neoproterozoic (not comparable)
(geology) Of a geologic era within the Proterozoic eon; comprises the Tonian, Cryogenian and Ediacaran periods from about 1000 to 544 million years ago, when algae and sponges flourished.
Neoproterozoic
(geology) The Neoproterozoic era.
Examples
Emerging evidence suggests that the Earth underwent a number of glaciations during the Neoproterozoic, which would stand strongly at odds with the snowball hypothesis.
Possibly as a consequence of the low-latitude position of most continents, several large-scale glacial events occurred during the Neoproterozoic Era including the Sturtian and Marinoan glaciations of the Cryogenian.
Extensive lava flows and volcanic eruptions of Neoproterozoic age are found on most continents, evidence for large scale rifting about 750 million years ago.
However, in 2004, the International Union of Geological Sciences ratified the Ediacaran age to be a geological age of the Neoproterozoic, ranging from to million years ago.
Long before the advent of the snowball Earth hypothesis many Neoproterozoic sediments had been interpreted as having a glacial origin, including some apparently at tropical latitudes at the time of their deposition.
Palaeomagnetic measurements have indicated that some sediments of glacial origin in the Neoproterozoic rock record were deposited within 10 degrees of the equator, citation although the accuracy of this reconstruction is in question.