Arkeyaan

Arkeyaan, oo hore loo yiqiin Arkeyosoyig, waxay ahaayeen eonka julooqika ka hor Broterosoyig oo dhammaaday 2500 milyan oo sano ka hor.  Xadkan looma go'aamin istraatigrafi ahaan ee waa qaab keronometerig ah.  Meesha laga bilaabayo muddadan si rasmi ah uma aqoonsana Guddiga Caalamiga ah ee Istaraatiijiyadda, laakiin waxaa badanaa loo maleynayaa inay dhacday 3800 milyan oo sano ka hor, dhammaadka eonka Hadeyaan.  Arkeyaan-yadu waxay ka kooban yihiin afar xilli, siday u kala horreeyaan: Eoarkeyaan, Balyuuarkeyaan, Mesoarkeyaan, iyo Neoarkeyaan.

Dhacdooyinka Arkeyaan
Siyanobakteriya badan 
Badweynta cagaaran
Sameynta qaaradaha sare
Baraf badan oo ku yaal Antarktika

Tixraac
GeoWhen (firfircoonayn)
Archean