Proterozoic

Definitions

  • WordNet 3.6
    • adj proterozoic formed in the later of two divisions of the Precambrian era "proterozoic life forms"
    • n Proterozoic from 2,500 to 544 million years ago; bacteria and fungi; primitive multicellular organisms
    • ***
Century Dictionary and Cyclopedia
    • Proterozoic Of or pertaining to the life existing before the time of the Cambrian or first fossils: a term originally proposed as a substitute for Azoic, Eozoic, Archæan, etc., in order to avoid the assertions contained in these words if taken literally.
    • n Proterozoic The time during which the simplest life-forms were developed: applied to the interval between the Archeozoic and Paleozoic as used by Chamberlin and Salisbury. It is assumed that life existed, but no determinable forms have yet been found. The subdivisions of the Proterozoic are Keweenawan, Animikean, and Huronian.
    • ***

Usage

In literature:

Moreover, they could live in most latitudes, for the indirect evidences of life in the Archeozoic and Proterozoic rocks are widely distributed.
"Climatic Changes" by Ellsworth Huntington
***

In science:

The Neo-Proterozoic (1000 - 550 Myr BP) was probably an intrinsically cooler period in Earth’s history, and glaciation was more abundant than in the Phanerozoic.
The Spiral Structure of the Milky Way, Cosmic Rays, and Ice Age Epochs on Earth
Also depicted are the periods during which glaciations were seen on Earth: The late Archean (3 Gyr) and mid-Proterozoic (2.2-2.4 Gyr BP) which correlate with the previous LMC perigalacticon passage , , and the consequent SFR peak in the MW and LMC.
The Spiral Structure of the Milky Way, Cosmic Rays, and Ice Age Epochs on Earth
The late Neo-Proterozoic ice ages correlate with a less clear SFR peak around 500-900 Myr BP.
The Spiral Structure of the Milky Way, Cosmic Rays, and Ice Age Epochs on Earth
The Proterozoic part is its extension using the data in Crowell.
The Spiral Structure of the Milky Way, Cosmic Rays, and Ice Age Epochs on Earth
Data gathered from seismic experiments were averaged globally for similar geological and tectonic settings (such as Archean, early Proterozoic, rifts, etc.).
Geo-neutrinos and Earth's interior
***