Early Earth

<p>Early Earth also known as proto-earth is loosely defined as encompassing <a href="/facts/Earth/HLLmDfj0">Earth</a> in its first one billion years, or <a href="/facts/Year/51V242hh">gigayear</a> (Ga, 109 y), from its initial formation in the young Solar System at about 4.55 Ga to some time in the <a href="/facts/Archean/PHt8Sm8n">Archean</a> eon in approximately 3.5 Ga. On the <a href="/facts/Geologic_time_scale/vBAm0D8Q">geologic time scale</a>, this comprises all of the <a href="/facts/Hadean/j7LWS4ah">Hadean</a> eon, starting with the formation of the Earth about 4.6 billion years ago, and the <a href="/facts/Eoarchean/q7KzQNHD">Eoarchean</a>, starting 4 billion years ago, and part of the <a href="/facts/Paleoarchean/5cldXjwo">Paleoarchean</a> era, starting 3.6 billion years ago, of the Archean eon.
</p><p>This period of <a href="/facts/History_of_Earth/0aEAQF0k">Earth's history</a> involved the planet's formation from the <a href="/facts/Solar_nebula/cgElXHpM">solar nebula</a> via a process known as <a href="/facts/Accretion_(astrophysics)/atcWRsDP">accretion</a>. This time period included intense <a href="/facts/Meteorite/NsmHlBlX">meteorite</a> bombardment as well as giant impacts, including the <a href="/facts/Giant-impact_hypothesis/x2cw2Xxn">Moon-forming impact</a>, which resulted in a series of <a href="/facts/Magma_ocean/PGcKDMRg">magma oceans</a> and episodes of <a href="/facts/Planetary_differentiation/fvjC1107">core formation</a>. After formation of the core, meteorites or comets may have delivered water and other volatile compounds to the Earth in a "late veneer". Although little crustal material from this period survives, the <a href="/facts/Oldest_dated_rocks/gR7PoRR0">oldest dated specimen</a> is a <a href="/facts/Zircon/84APfbLt">zircon</a> mineral of 4.404 ± 0.008 <a href="/facts/Gigaannum/51V242hh">Ga</a> enclosed in a <a href="/facts/Metamorphism/8eWHgy6K">metamorphosed</a> <a href="/facts/Sandstone/RP8B6fqL">sandstone</a> <a href="/facts/Conglomerate_(geology)/llpnLX76">conglomerate</a> in the <a href="/facts/Jack_Hills/CaDaRdue">Jack Hills</a> of the <a href="/facts/Narryer_Gneiss_terrane/eNCgCpND">Narryer Gneiss terrane</a> of <a href="/facts/Western_Australia/1ouCbwNh">Western Australia</a>. The earliest <a href="/facts/Supracrustal/IslJg6wj">supracrustals</a> (such as the <a href="/facts/Isua_greenstone_belt/QGMG0uPp">Isua greenstone belt</a>) date from the latter half of this period, about 3.8 Ga, around the same time as peak <a href="/facts/Late_Heavy_Bombardment/PBUlnPJX">Late Heavy Bombardment</a>.
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Early Earth open-in-new

Early Earth