Esikhatsini seSakhiwo se Ningizimu Afrika
Licembu Lekuphtsa
Kungumcabango kutsi tinshwana letincane telicembu le sive sentiwa kuminyaka lengaba ngu 3.07 yemakhulu netigidzi teminyaka yandvulo, esigodzini lesasikadze sinetinkinga letakhiwa ngesikhatsi tintfo letingaphansi kwencenye yemhlaba ticala kululeka. Lokukukhatsateka kwabese kugcwaliseka ngekwakhiwa kungenela kusuka ku mantle. Letinye taletintfo teLicembu Lemhlaba tatitfwele ligolide, lelalikadze ligujwe emayini ngemphumelelo lencane.
Kute lokungakanani ngalelicembu Lemhlaba lokwatikwako, njengoba konkhe loku kwenteka esikhatsini sakadzeni futsi timbalwa tindzawo lapho lamatje asegcinekile. Kulendzawo ye Vredefort, ngesibonelo nje, Lelicembu Lemhlaba lichazeka ngalencenye yalo lencane yelitje lelincibilikile lelibonakala kuyinye noma timbili tindzawo.
Ngemuva kweLicembu Lemhlaba selilele phansi, tincenye te mhlaba we Kaapvaal tabheka phansi noma tashona phansi tindishi takhukhuleka ngemanti. Loku kwenta intfo lokukhulu, lwandle lolushonako ikakhulu etifundzeni kantsi netikali letinkhulu letacala ematje lamancane. Ngalesi sikhatsi, kumcoka kutsatsa kubuka dvute umsebenti lowentiwa ngemanti ngendlela yematje lamancane lakhiwa tinshwana.
Inkundla Lenkhulu I Witwaterand
Ecinisweni, tintfo letihambisa emanti tiyahlukaniseka etintfweni tematje. Lokugijima kwalamanti kuvame kukala libanga lelihanjwa nguletintfo. Uma imifula ifika kumitimba lemikhulu yemanti (sitiba noma lwandle), lokuhamba kwlamanti kuyancipha bese incumbi yetinfo letesendzako tehlela phansi bese tindanda ngetulu. Tintfo letilula, letifana nesihlabatsi kanye neludzaka, tisala tinyamalala kulamanti sikhatsi lisedze bese tiyakhweshiseka ngaselusentseni lwemanti. Lesizatfu lesingenta nginitjele konkhe loku kutsi titovela muva.
Ngako, iminyaka yasendvula lengaba ngu 2.97 yemakhulu etigidzi, tincenye letiningi tematje lakhiwe ngaletinye tintfo tehlela phansi kulolwandle lolushonako loluvala liningi lelilanga lelikhona lase Ningizimu Afrika. Loku kubitwa nge West Rand Group futsi kwakhe tintfo letiningi letichazanako, njengentfo lechaza iWitwatersrand ridge legijima phakatsi kwe Germiston ne Krugersdorp.
Ngalesinye sikhatsi muva, incenye yemhlaba iyaphakama kancane bese nalomhlaba ugucuka uba yinombolo lephakeme kanye netindishi. Lemifula nyalo yabalekela kusuka etindzaweni letisetulu enyakatfo kanye nase nshonalanga yemachibi kanye netinkinga, lapho kwabalukhuni kukunaka. Lamatje lakheka ngalesisikhatsi abitwa ngekutsi yi Witwatersrand Supergroup.
Sikatsi Lesimangalisako
Licembu le Central Rand lalicishe limcoka, nomakunjalo, ngoba tinhlanyelo letisindzako teligolide taphumela kulemibhedze lesindzako, kanye kanye nalesihlabatsi. Loku kwasungula ludlelo loludulile lweligolide eMhlabeni, lutfwele cishe ihhavu yegolide yemhlaba. Muva, leli ligolde lelakhiwako lihlanganisa incenye yematje (labitwa ngema reefs) ayagujwa ngemphumelelo letsite. Intfo lengiyo mbamba yaletinshwana letincane teligolide, nomakunjalo, isala ibe yintfo yesikhatsi lesimangalisako.
Ngetikhatsi ta 2.7 yemakhulu etigidzi tandvulo, Lencenye Yemhlaba we Kaapvaal yashayisana nemhlaba wase Zimbabwe kuya enyakatfo. Loku kwakha intsaba ye mammoth leyakhulela ngasendzaweni lebitwa ngekutsi yi Limpopo Mobile Belt. Nayo yaphumela yaya kulelitje lelincibilikako lelavela licitsekela kumikhatsi yencenye yemhlaba, lokwavala lamathe eWitwatersrand Supergroup. Lenamincibiliko yakha incenye ngetulu kwe Ventersdorop Supergroup.
Licembu Lelikhulu lase Transvaal
Kuchubekala phambili kancane, nga 2.5 wemakhulu etigidzi teminyaka yakadzeni, lencenye yemhlaba yaphendvuka futsi yabese icishe iba yintfo lengaphansi kwemanti ngelwandle lendzawo lengekhatsi. Loku kwasusa lenye intfo yematje lakhiwe tintfo letincane lasindzako kwaphindze kwamaka kucala kwe Transvaal Supergroup. Loku kuphindze kuhlangane ne kuphela kwe Archaean kanye nekucala kwe Proterzoic era, lokwatsatsa iminyaka lengemakhulu nemashumi lasikhombisa etigidzi teminyaka tandvulo.
Le Traansvaal Supergroup isicumbi lesichazako sematje. Incenye lephansi, lebitwa nge Black Reef Formation, itfwele tintfo teligolide. Ngetulu kwaloko li Cembu le Chuniespoort. Lenancenye itfwele lizibithi laletinye tintfo tasekucaleni kwemphilo yeMhlaba – iphotosynthesising cyanobacteria. Yebo, akuvakali kuchaza loku, kepha.
Translated by
Phindile Malotana