The second of two eons in the Precambrian period, lasting from 2500 to 570 Ma. It is preceded by the Archean eon and followed by the Phanerozoic eon, and is comprised of the Early (2500-1600 Ma), Middle (1600-900 Ma), and Late (900-570 Ma) eras. It is characterized by the earliest forms of life on earth.
Rocks formed between 2,500 and 600 million years ago.
The later part of Precambrian time (2500-590 million years ago).
The most recent of the Precambrian eons.
(= Cryptozoic) is one of three major subdivisions (eons) of Earth crust history, that lasted from 2600 until 590 mln years B.P.
means the more recent of the two great divisions of the Precambrian.
The more recent of the two divisions of the Precambrian. View timeline of geologic events.
from 2,500 to 544 million years ago; bacteria and fungi; primitive multicellular organisms
formed in the later of two divisions of the Precambrian era; "proterozoic life forms"
Eon of Precambrian time from 2.5 billion years to the base of the Cambrian. It is divided into three eras and ten periods that are classified on the basis of their radiometric ages.
Upper Precambrian deposits.
It is a period of geological time which is the uppermost of the two main Precambrian divisions. It extends from 2500 to 545 million years ago.
The final era of the Precambrian, spanning the time between 2.5 billion and 544 million years ago. Fossils of both primitive single celled and more advanced multicellular organisms begin to appear in abundance in rocks from this era. Its name means "early life."
(see Geological Timescale)
the eon of geologic time from 2500 Ma to 540 Ma.
Period of Earth's history from 2.5 billion to 600 million years ago.
An era of geological time spanning the period from 2,500 million years to 570 million years before present.
a time period roughly 2.7 billion to 570 million years ago.
That part of the Precambrian time represented by rocks in which traces of life appear or the younger part of Precambrian time.
Geologic eon that occurred from 570 to 2500 million years ago. During this time period, the first single-celled and multi-celled eukaryotic organisms evolved and developed.
the later of two divisions of the Precambrian time, during which sponges, sea worms, and other forms of sea life appeared; the rocks formed during this time. [AHDOS
The Proterozoic (IPA: ) is a geological eon representing a period before the first abundant complex life on Earth. The Proterozoic Eon extended from 2500 Ma to 542.0 ± 1.0 Ma (million years ago). The Proterozoic is the most recent part of the old informal Precambrian time.