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The Hadean (/ h eɪ ˈ d iː ə n, ˈ h eɪ d i ə n / hay-DEE-ən, HAY-dee-ən) is the first and oldest of the four known geologic eons of Earth's history, starting with the planet's formation about 4.6 billion years ago [4] [5] (estimated 4567.30 ± 0.16 million years ago [2] set by the age of the oldest solid material in the Solar System — protoplanetary disk dust particles — found as ...
2.1 Hadean Eon. 2.2 Archean Eon. 2.3 Proterozoic Eon. 2.4 Phanerozoic Eon. ... Oldest evidence for microbial life on land in the form of organic matter-rich paleosols
The oldest dated rocks formed on Earth, as an aggregate of minerals that have not been subsequently broken down by erosion or melted, are more than 4 billion years old, formed during the Hadean Eon of Earth's geological history, and mark the start of the Archean Eon, which is defined to start with the formation of the oldest intact rocks on Earth.
The first eon in Earth's history, the Hadean, begins with the Earth's formation and is followed by the Archean eon at 3.8 Ga. [2]: 145 The oldest rocks found on Earth date to about 4.0 Ga, and the oldest detrital zircon crystals in rocks to about 4.4 Ga, [34] [35] [36] soon after the formation of the Earth's crust and the Earth
c. 4,533 Ma – Hadean Eon, Precambrian Supereon and unofficial Cryptic era start as the Earth–Moon system forms, possibly as a result of a glancing collision between proto-Earth and the hypothetical protoplanet Theia (the Earth was considerably smaller than now, before this impact). This impact vaporized a large amount of the crust, and sent ...
The Cryptic era is an informal term for the earliest geologic evolution of the Earth and Moon.It is the oldest (informal) era of the Hadean eon, and it is commonly accepted to have begun close to about 4.533 billion years ago when the Earth and Moon formed, and lasted to about 4.15 billion years ago.
The Precambrian includes approximately 90% of geologic time. It extends from 4.6 billion years ago to the beginning of the Cambrian Period (about 539 Ma).It includes the first three of the four eons of Earth's prehistory (the Hadean, Archean and Proterozoic) and precedes the Phanerozoic eon.
Early Earth also known as proto-earth is loosely defined as encompassing Earth in its first one billion years, or gigayear (Ga, 10 9 y), [1] from its initial formation in the young Solar System at about 4.55 Ga to some time in the Archean eon in approximately 3.5 Ga. [2] On the geologic time scale, this comprises all of the Hadean eon, starting ...