• Tuisblad
  • Afrika
  • Korrels van Vredefort-koepel se meteoriet in Noord-Kaap gekry
Korrels van Vredefort-koepel se meteoriet in Noord-Kaap gekry
Korrels van Vredefort-koepel se meteoriet in Noord-Kaap gekry

Korrels van Vredefort-koepel se meteoriet in Noord-Kaap gekry

Navorsing bewys die skokminerale is 1,6 miljoen jaar gelede deur die Vaalrivier afgevoer en as sandkorrels begrawe.
Onlangse navorsing bewys dat sandkorrels by Kantienkopje in Barkly-Wes, Noord-Kaap, miljoene jare gelede deel was van meteorietrotse wat die aarde getref het en die Vredefort-koepel in Gauteng gevorm het.

Dr. Aaron Cavosie, navorser van die Curtin-universiteit in Perth, Australië, en sy medenavorser, dr. Ryan Gibbon van die Universiteit van Kaapstad, het bevind dat die Rietputsformasie naby Kantienkopje op die Vaalrivier waardevolle bewyse hiervan het.

Volgens Cavosie het die drastiese impak van die meteoriet enorme skokgolwe deur die aardkors gestuur en skade berokken. Plekke waar die impak groot was, het vandag waardevolle nikkel- en goudneerslae.

Oor die millennia heen het die meteorietrotse tot sandkorrels erodeer wat deur water, ys en wind weggevoer is. Al oorblywende teken van die impak is die krater.

Cavosie en Gibbon en andere het die erodering by die Vredefort-koepel, die aarde se grootste (deursnit van 300 km) en oudste (twee miljard jaar) krater, bestudeer.

Die sogenaamde skokminerale van die impak teen die aardkors bevat kwartsiet, monasiet en sirkoon, wat die mikroskopiese bewyse van die meteorietbotsing se skade bewaar. Dit is uniek aan meteorietbotsings.

Hul navorsing bewys die skokminerale is 1,6 miljoen jaar gelede deur die Vaalrivier afgevoer en as sandkorrels begrawe.

Die navorsers het die afgelope dekade bevind dat dié skokminerale deur die Vaal- en Oranjerivier tot so ver as Alexanderbaai, 2 000 km verder, weggevoer is.

Die vraag was hoe lank die sediment behoue bly.

In hul navorsing beskryf hulle die oer-Vaalrivier se sedimentneerslae van die Vredefort-koepel wat by Barkly-Wes, Windsorton en Douglas gevind is. Dit word ook ontbloot by diamantmyne op die Vaalrivier.

Die Rietputformasie (1,6 miljoen jaar oud) by Kantienkopje bevat benewens die skokminerale ook groot versamelings steentydperk-handwerktuie.

Hul navorsing bewys die skokminerale is 1,6 miljoen jaar gelede deur die Vaalrivier afgevoer en as sandkorrels begrawe. Uranium-lood-toetse op die sandkorrels toon dit kom beslis van die Vredefort-koepel, sowat 500 km stroomop.

Die ontdekking en navorsing benadruk die noodsaaklikheid daarvan dat Kantienkopje as erfenisterrein en ook as ’n geologiese argief bewaar moet word omdat daar geen ander terrein is waar die skokminerale ongeskonde gevind word nie. Kantienkopje bevat ook ander argeologiese skatte. –Netwerk24

Kommentaar

Republikein 2024-05-02

Geen kommentaar is op hierdie artikel gelaat nie

Meld asseblief aan om kommentaar te lewer

LaLiga: Barcelona 4 vs 2 Valencia SerieA: Genoa 3 vs 0 Cagliari European Championships Qualifying: Coventry City 1 vs 2 Ipswich Town | Preston North End 0 vs 3 Leicester City English Championship: Coventry City 1 vs 2 Ipswich Town | Preston North End 0 vs 3 Leicester City Katima Mulilo: 12° | 33° Rundu: 12° | 31° Eenhana: 14° | 33° Oshakati: 16° | 32° Ruacana: 15° | 32° Tsumeb: 15° | 31° Otjiwarongo: 14° | 29° Omaruru: 15° | 32° Windhoek: 13° | 27° Gobabis: 15° | 28° Henties Bay: 16° | 21° Wind speed: 40km/h, Wind direction: E, Low tide: 04:26, High tide: 10:41, Low Tide: 16:45, High tide: 23:19 Swakopmund: 16° | 18° Wind speed: 30km/h, Wind direction: S, Low tide: 04:24, High tide: 10:39, Low Tide: 16:43, High tide: 23:17 Walvis Bay: 17° | 25° Wind speed: 30km/h, Wind direction: S, Low tide: 04:24, High tide: 10:38, Low Tide: 16:43, High tide: 23:16 Rehoboth: 15° | 29° Mariental: 18° | 31° Keetmanshoop: 20° | 32° Aranos: 18° | 30° Lüderitz: 14° | 25° Ariamsvlei: 20° | 34° Oranjemund: 14° | 22° Luanda: 25° | 28° Gaborone: 16° | 29° Lubumbashi: 11° | 26° Mbabane: 14° | 25° Maseru: 10° | 26° Antananarivo: 15° | 25° Lilongwe: 14° | 28° Maputo: 18° | 28° Windhoek: 13° | 27° Cape Town: 16° | 24° Durban: 18° | 26° Johannesburg: 17° | 26° Dar es Salaam: 26° | 30° Lusaka: 15° | 27° Harare: 13° | 27° Currency: GBP to NAD 23.18 | EUR to NAD 19.86 | CNY to NAD 2.56 | USD to NAD 18.53 | DZD to NAD 0.14 | AOA to NAD 0.02 | BWP to NAD 1.32 | EGP to NAD 0.38 | KES to NAD 0.14 | NGN to NAD 0.01 | ZMW to NAD 0.68 | ZWL to NAD 0.04 | BRL to NAD 3.58 | RUB to NAD 0.2 | INR to NAD 0.22 | USD to DZD 133.94 | USD to AOA 834.06 | USD to BWP 13.64 | USD to EGP 47.9 | USD to KES 134.48 | USD to NGN 1349.9 | USD to ZAR 18.53 | USD to ZMW 26.87 | USD to ZWL 321 | Stock Exchange: JSE All Share Index 76076.19 Down -0.5% | Namibian Stock Exchange (NSX) Overall Index 1690.93 Down -0.96% | Casablanca Stock Exchange (CSE) MASI 13322.85 Up +0.03% | Egyptian Exchange (EGX) 30 Index 26113.71 Up +6.81% | Botswana Stock Exchange (BSE) DCI 9146.09 Same 0 | NSX: MTC 7.75 SAME | Anirep 8.99 SAME | Capricorn Investment group 17.34 SAME | FirstRand Namibia Ltd 49 DOWN 0.50% | Letshego Holdings (Namibia) Ltd 4.1 UP 2.50% | Namibia Asset Management Ltd 0.7 SAME | Namibia Breweries Ltd 31.49 UP 0.03% | Nictus Holdings - Nam 2.22 SAME | Oryx Properties Ltd 12.1 UP 1.70% | Paratus Namibia Holdings 11.99 SAME | SBN Holdings 8.45 SAME | Trustco Group Holdings Ltd 0.48 SAME | B2Gold Corporation 47.34 DOWN 1.50% | Local Index closed 677.62 UP 0.12% | Overall Index closed 1534.6 DOWN 0.05% | Osino Resources Corp 19.47 DOWN 2.41% | Commodities: Gold US$ 2 307.34/OZ UP +0.69% | Copper US$ 4.47/lb DOWN -0.0074 | Zinc US$ 2 923.50/T UP 0.18% | Brent Crude Oil US$ 84.56/BBP DOWN -0.0245 | Platinum US$ 955.09/OZ UP +2.18% Sport results: LaLiga: Barcelona 4 vs 2 Valencia SerieA: Genoa 3 vs 0 Cagliari European Championships Qualifying: Coventry City 1 vs 2 Ipswich Town | Preston North End 0 vs 3 Leicester City English Championship: Coventry City 1 vs 2 Ipswich Town | Preston North End 0 vs 3 Leicester City Weather: Katima Mulilo: 12° | 33° Rundu: 12° | 31° Eenhana: 14° | 33° Oshakati: 16° | 32° Ruacana: 15° | 32° Tsumeb: 15° | 31° Otjiwarongo: 14° | 29° Omaruru: 15° | 32° Windhoek: 13° | 27° Gobabis: 15° | 28° Henties Bay: 16° | 21° Wind speed: 40km/h, Wind direction: E, Low tide: 04:26, High tide: 10:41, Low Tide: 16:45, High tide: 23:19 Swakopmund: 16° | 18° Wind speed: 30km/h, Wind direction: S, Low tide: 04:24, High tide: 10:39, Low Tide: 16:43, High tide: 23:17 Walvis Bay: 17° | 25° Wind speed: 30km/h, Wind direction: S, Low tide: 04:24, High tide: 10:38, Low Tide: 16:43, High tide: 23:16 Rehoboth: 15° | 29° Mariental: 18° | 31° Keetmanshoop: 20° | 32° Aranos: 18° | 30° Lüderitz: 14° | 25° Ariamsvlei: 20° | 34° Oranjemund: 14° | 22° Luanda: 25° | 28° Gaborone: 16° | 29° Lubumbashi: 11° | 26° Mbabane: 14° | 25° Maseru: 10° | 26° Antananarivo: 15° | 25° Lilongwe: 14° | 28° Maputo: 18° | 28° Windhoek: 13° | 27° Cape Town: 16° | 24° Durban: 18° | 26° Johannesburg: 17° | 26° Dar es Salaam: 26° | 30° Lusaka: 15° | 27° Harare: 13° | 27° Economic Indicators: Currency: GBP to NAD 23.18 | EUR to NAD 19.86 | CNY to NAD 2.56 | USD to NAD 18.53 | DZD to NAD 0.14 | AOA to NAD 0.02 | BWP to NAD 1.32 | EGP to NAD 0.38 | KES to NAD 0.14 | NGN to NAD 0.01 | ZMW to NAD 0.68 | ZWL to NAD 0.04 | BRL to NAD 3.58 | RUB to NAD 0.2 | INR to NAD 0.22 | USD to DZD 133.94 | USD to AOA 834.06 | USD to BWP 13.64 | USD to EGP 47.9 | USD to KES 134.48 | USD to NGN 1349.9 | USD to ZAR 18.53 | USD to ZMW 26.87 | USD to ZWL 321 | Stock Exchange: JSE All Share Index 76076.19 Down -0.5% | Namibian Stock Exchange (NSX) Overall Index 1690.93 Down -0.96% | Casablanca Stock Exchange (CSE) MASI 13322.85 Up +0.03% | Egyptian Exchange (EGX) 30 Index 26113.71 Up +6.81% | Botswana Stock Exchange (BSE) DCI 9146.09 Same 0 | NSX: MTC 7.75 SAME | Anirep 8.99 SAME | Capricorn Investment group 17.34 SAME | FirstRand Namibia Ltd 49 DOWN 0.50% | Letshego Holdings (Namibia) Ltd 4.1 UP 2.50% | Namibia Asset Management Ltd 0.7 SAME | Namibia Breweries Ltd 31.49 UP 0.03% | Nictus Holdings - Nam 2.22 SAME | Oryx Properties Ltd 12.1 UP 1.70% | Paratus Namibia Holdings 11.99 SAME | SBN Holdings 8.45 SAME | Trustco Group Holdings Ltd 0.48 SAME | B2Gold Corporation 47.34 DOWN 1.50% | Local Index closed 677.62 UP 0.12% | Overall Index closed 1534.6 DOWN 0.05% | Osino Resources Corp 19.47 DOWN 2.41% | Commodities: Gold US$ 2 307.34/OZ UP +0.69% | Copper US$ 4.47/lb DOWN -0.0074 | Zinc US$ 2 923.50/T UP 0.18% | Brent Crude Oil US$ 84.56/BBP DOWN -0.0245 | Platinum US$ 955.09/OZ UP +2.18%