Archean | Aeon
The (also spelled Archaean ) is a major division of geologic time extending from 4.0 to 2.5 billion years ago (Ga) . It follows the Hadean and precedes the Proterozoic aeon. The name is derived from the Greek word for "beginning," as it represents the earliest substantial part of the Earth's rock record. Geological and Tectonic Environment
During this period, the Earth transitioned from a high-heat "stagnant-lid" or "proto-subduction" state into a more modern style of global plate tectonics. archean aeon
: The end of the Archean (3.0–2.5 Ga) marked the global initiation of "modern-style" subduction-collision cycles as the planet cooled. Atmosphere and Climate The (also spelled Archaean ) is a major
: The Archean Earth was primarily a water world, with much of the early continental crust submerged under oceans deeper than those of today. Geological and Tectonic Environment During this period, the
: The Earth's crust began to stabilize, forming ancient continental nuclei known as cratons .