Luphenyo lwe Vredefort Lesandingilizi
Bacwalingi Bendzawo
Emuva eNingizimu Afrika, nomakunjalo, lentfutfuko yesisindvo sesayensi sabukeka sitosengca. Nga 1916, S.J. Shand wacala wachaza lokuncibilika kwelitje lelihle walibita 'pseudotachylite' kepha akazange asho kutsi imvelaphi yalelitje. Lucwalingo lwekucala lwalendzawo lesandingilizi, leyatsatfa nga 1925, yefika emaphetselweni kutsi lendzawo lesandingilizi yentiwa kugedvuka kwemhlaba lokukhulu ngemoya lowabhoma. Nga 1936, bacwalingi lababili baveta kutsi sisindvo sente lendzawo lesandingilizi, kepha loku akuzange kutsatselwe etulu bacwalingi bendzawo.
Lobekuvimba kwakungiso lesakhiwo salendzawo lesandingilizi cobolwaso. Kungenteka njani kutsi sisindvo lesiphuma etulu sente umhlaba kutsi uphakame? Ngeliciniso kubhoma kwangekhatsi noma kungenelela kwabangiko lokwakha kuphakama kunesisindvo sangephandle. Nanobekunjalo, nga 1947, umfundzi wematje ne mhlaba lobitwa ngekutsi ngu R.A. Daly wabona sisindvo wase utsi lokukhululeka kwemoya ngemuva kwesisindvo kungaba ngiko lokungenta litje kutsi lubuye bese liphakamisa lesakhiwo sendzawo lesandingilizi. Lobabe wemazulu wangengci yase Ningizimu Afrika, Alex du Toit, wasala angakanetiseki wase uchaza kutsi lendzawo lesandingilizi yakhiwa ngetindlela tesakhiwo sangetulu nekunyakata kwako.
Lokuphikisana Kwachubeka
Iminyaka lemine, lokuphikisana kwachubeka. Umcondvo wangaphesheya wacala kubukwa ngelisayidi lwesikolwa sesisindvo. Kepha bacwalingi base Ningizimu Afrika bachubeka kukhokha emaphepha bancoma kwangekhatsi (kwemaginethi noma sakhiwo sangetulu nekunyakata kwako) kweliciniso. Nga 1960, kwaphuma umbiko ku Mfundzi wemhlaba nematje wase Ottawa lowenta umehluko locacako emkhatsini wetinhlobo letimbili temigodzi: leyo lene diameter lekala lokuphansi kunemakhilomitha lambalwa, lokwenta kube nekuphakama kwemkhatsi bematje lamadzala lagegetelwe tincenye letincane.
Loku 'kuhlangahlanganisa' indlela yemgodzi lefakwe kahle eVredefort. Nomakunjalo, bososayensi bakulendzawo bachubeka ngendlela yabo, banikela tinhlito tabo kulomsebenti Wangaphesheya we crypto-explosion, Walter Butcher, lowagcina kutsi sakhiwo sendzawo lesandingilizi sentiwa kuphazamiseka kwemoya loshisako lowaphuma kumalayini lalula kutimvutfu Temhlaba.
iMetamorphic Letfusako
Ngaphandle kwelucwalingo lebendzawo, kuvisisa kwe metamorphic letfusako yachubeka kukhula. Nga 1968, umhlangano lomkhulu wangaphesheya kulesifundvo wabanjwa, wahlanganisa tati letiphuma kumave lamaningi.Loku kwanika lomsebenti intfo lensha, eminyakeni lengetulu letako, kuhamaba lokudze kwenteka. Imibhalo yemigodzi, tibonelo telitje le lunar kanye nemiphumela yase labhorethri tachubeka kushayisana naletinye, kwatsi tikali tacala kukhwebuka macondzana nesisindvo. Ngekuphela kwa 1970, sakhiwo sesisindvo lesilikhulu nemashumi lamabili sabonwa etindzaweni letiningi talomhlaba kanye nesicumbi selitje lelitsite sakha lokufanako kumigodzi leminingi leseyichaziwe. Lawa matje nasahlangene abitwa nge 'nhlanganisela' - ligama lelibuyisa engcondvweni emalunga elikilasi le aerobics, noma bantfu lasicumbi ekheshini.
Ngemnyaka wa 1980, tati letiningi tangaphesheya tatsemba kantsi nemaNyuvesi angaphandle abefundzisa kutsi le Vredefort Lesandingilizi yakhiwa ngesisindvo sentfo. Kepha hhayi eNingizimu Afrika. Lana, dzangamanti (lachutjwa ngumfundzi wemhlaba nematje Louis Nicolaysen) wagcina ematsemba abo nge crypto-volcanic lengiyo yalendzawo lesandingilizi. Ekugcineni, lomhlangano wabitelwa kucedza lokungavani. Wabanjelwa eParys ngemnyaka wa 1987 kwatsi netati letiphuma khempu omabili atisa lomhlangano. Lomhlangano awuphumelelanga kufika emaphetselweni, nomakunjalo, Ngekusho, kukhetsa kwenteka ekupheleni kwemhlangano kwatsi liningi lalabebakhona lakhomba kusekela iexogenic (sisindvo sangephandle) mbamba.
Esigabeni Seliningi
Kujuba indzaba lendze ibe yimfisha, umnyaka lolandzelako wawugcwele tindzaba lebetiphuma kubacwalingi base Ningizimu Afrika nebangaphandle kwemave emhlaba. Lendzawo lesandingilizi yaphushwa bafundzi bemhlaba nematje futsi, kancane, luphawu lwakhula. iCoesite kanye ne Shishovite yatfolwa, kwakheka lokuncane kumatje lamancane kwatfolwa futsi lokukahle kwemvelo ye metamorphism kumatje kwafundvwa. Ekugcineni, ngemnyaka wa 1997, Hughes Leroux wakhona kuchaza incenye yalamanye ematje ngesigaba seliningi. Lakutfola kwakhomba ngalokuphelele kutsi iVredefort Lesandingilizi yahlukumeteka nge sisindvo lesikhulu lokwakha lamatje ngendlela letsite. Lokungabata sekuze kwahlulekiswa ekugcineni.
Translated by
Phindile Malotana