The Archean Eon (IPA: / ɑːr ˈ k iː ə n / ar-KEE-ən, also spelled Archaean or Archæan), in older sources sometimes called the Archaeozoic, is the second of the four geologic eons of Earth's history, preceded by the Hadean Eon and followed by the Proterozoic and the Phanerozoic.

Jan 20, 2025 · The Archean Eon was preceded by the Hadean Eon, an informal division of geologic time spanning from about 4.6 billion to 4 billion years ago and characterized by Earth’s initial formation. Records of Earth’s primitive atmosphere and oceans emerge in the earliest Archean (Eoarchean Era).

The Archean (or Archaean) eon is an interval of geologic time of about 1.4 billion years, beginning with the formation of Earth's crust and the oldest Earth rocks 3,960-3,800 million years ago (mya) and continuing until its boundary at 2,500 mya, with the Proterozoic eon.

Sep 21, 2023 · Welcome to a journey back in time, where we explore the remarkable epoch known as the Archean Eon. This era, which spans roughly from 4 billion to 2.5 billion years ago, represents Earth’s formative years—a time of tumultuous geological changes, the emergence of life, and intriguing mysteries.

Archean Eon, or Archaean Eon or Archeozoic Eon, Older of the two divisions of Precambrian time. The Archean begins with the formation of the Earth’s crust 4 billion years ago and extends to 2.5 billion years ago, up to the start of the Proterozoic Eon, the second division of the Precambrian Period.

During the Archean Eon, which spanned from approximately 4 billion to 2.5 billion years ago, significant geological and biological events unfolded on Earth. Notably, this eon witnessed the formation of the first continents, the development of Earth’s early atmosphere, and the emergence of life in the form of simple, single-celled organisms ...

The Archean Eon, which lasted from 4.0–2.5 billion years ago, is named after the Greek word for beginning. This eon represents the beginning of the rock record. Although there is current evidence that rocks and minerals existed during the Hadean Eon, the Archean has a much more robust rock and fossil record.

The Archean (formerly Archaeozoic) is a geologic eon between the Hadean and Proterozoic eons. The Archean Eon begins at roughly 3.8 billion years ago (Ga) and ends at about 2.5 Ga. But unlike all other geological ages, which are based on stratigraphy, The Archean eon is defined chronometrically.

The Archean is the period in the earth 's history from about 3.8 to 2.5 billion years ago (Ga). The term was derived from the Latin word for first because the beginning of the Archean is defined as the age of the oldest rocks identified on Earth.

The Archean Eon (4 to 2.5 billion years ago) During the Archean Eon, methane droplets in the air shrouded the young Earth in a global haze. There was no oxygen gas on Earth. Oxygen was only in compounds such as water.