Qeybta dhexe ee barafka barafka waxaa hakad galiya joogitaanka godka Kibo. Barafka dushiisa iyo barafka dushiisa ma muujiyaan dhaqdhaqaaqyo jilicsan oo jilicsan sababtoo ah dhumucdooda hoose waxay ka hortagtaa isbeddello waaweyn. Caddaynta juqraafiyeed waxay muujineysaa shan dhacdo oo baraf ah oo isku xigxigay intii lagu jiray muddadii Quaternary, oo kala ah: Kowaad (500,000 BP), Labaad (in ka badan 360,000 sano ka hor ilaa 240,000 BP), Saddexaad (150,000 ilaa 120,000 BP), Afraad (oo sidoo kale loo yaqaan "Main") (20,000 ilaa 17,000 BP), iyo Yar (16,000 ilaa 14,000 BP).
11,700 oo sano