proterozoic

/prot-er-uh-zoh-ik, proh-ter-/US // ˌprɒt ər əˈzoʊ ɪk, ˌproʊ tər- //UK // (ˌprəʊtərəʊˈzəʊɪk) //

原生代,前生代,原生代的,近生代

Definitions

adj.形容词 adjective

1
- : noting or pertaining to the latter half of the Precambrian Era, from about 2.5 billion to 570 million years ago, characterized by the appearance of bacteria and marine algae; Algonkian.

n.名词 noun

1
- : the Proterozoic division of geologic time or the rock systems formed then; Algonkian.

Proterozoic , the age of invertebrate dominance, containing an early and a late ice age.
Proterozoic fossils have been found in places where the present average temperature approaches 0°C.
The recent discovery of glaciation in latitudes as low as 30° in the Proterozoic is correspondingly significant.
Hence, uplift alone cannot account for extensive glaciation in subtropical latitudes during the Permian and Proterozoic.
The late Proterozoic or very earliest Cambrian was probably the time of the great splitting up into groups.