Indlela Ema Meteors Angenela ngayo Umhlaba

© David Fleminger

Interplanetary Projectiles

Uma ubuka kundzawo lengaphandle kwemhlaba nakumnyama ebusuku, konkhe kubukeka kunekuthula. Tinkhanyeti kulesibhakabhaka lesimnyama lesikhanyako kanye ne kungabikhona kwendzawo lengaphandle kwemhlaba ngetulu kwenhloko. Kepha umhlaba uhlukile. Lomhlaba uyagcwaliswa ngetintfo,ikakhulu letitsetfwe kutintfo letincane letilibhande emkhatsini we Mars ne Jupiter. Lokukuhlaselwa ngekushesha kwachubeka sikhatsi futsi, lokungumcabango kutsi inombolo yemaplanetary projectiles iphansi kakhulu namuhla kunendlela beyingiyo ngesikhatsi umhlaba bowakhiwa, kucatjangwa kutsi emathani latinkhulungwane letimashumi lamatsatfu etintfo letisele natibulawa te planetary letisangena emoyeni wetfu mnyaka wonkhe.

Liningi laletintfo letincane natisha natiwa ngekushesha kumoya, ishise ngetulu kwendzawo yekuncibilika ngekwala kwemoya. Lelilambu lelikhanyako lelihanjiswa nguletintfo litenta tibonakale njengemameteors, noma kudubula tinkhanyeti. Umangabe le meteor iyinkhulu kahle, nomakunjalo, incenye yayo ingaphila kulokushisa nakulendzawo emhlabeni njenge meteorite. Ngelwati Lwakho, imeteorite leyatfolwa yebo ikhashane ngule Hoba meteorite, leyatfolwa ngemnyaka wa 1920. Itsintsa umhlaba eceleni kwe Grootfontein, enyakatfo ye Namibia, ngetulu kweminyaka letinkhulungwane letimashumi lasiphohlongo kadzeni futsi ayikasuswa kusukela lapho. Hoba yincenye lecinile ye ayoni kanye ne nickel, ikala emamitha lacishe abematsatfu bese linye limitha liphakeme.

Sisindvo Lesikhulu

Kungabanjani uma intfo lenkhulu kakhulu ichamuka idvumela Emhlabeni? Kungentekani uma ibolide lekala lishumi noma emakhilomitha lalikhulu lecela emhlabatsini loshayekile? Kufundza taphambilini tesisindvo atipendi sonkhe sitfombe lesihle.

Tintfo letinkhulu tibukeka tinendlela yekubulala hhayi nje tintfo tesisindvo tendzawo, kepha indzawo yonkhe. Kutamatama kwemhlaba, ematsunami emikhumbi kanye nemanti lanemandla ekubhidlika laphuma esisindvweni itoklina lendzawo yemphilo. Ngekungeta kakhulu, tinombolo letinkhulu telutfuli kanye netintfo letincane letipheshuliwe emhlabeni tingavimba lilanga, tente lomhlaba ube yicatastrophic webusika lobutsatsatinyanga letiningi noma iminyaka. Ngalamafisha, kubekiwe kutsi tintfo tesisindvo tingenta kungabikho tintfo letiphilako ngesikali semhlaba.

Lokungasaphili

Lokungasaphili yincenye yemvelo yenchubo yengucuko. Ngetulu kwetigidzinetigidzi teminyaka, tilwane noma tintfo letiningi tifile ngenca yengucuko yesimo, umonakalo wemvelo kanye nemicudzelwano naletinye tilwane noma tintfo. Loku kutsatfwa kutsi yimphilo (noma limuva) lokungasaphili futsi kusachubeka nanamuhla-kusitwa bantfu bamanje labanyakata kulomhlaba. Kucatjangwa kutsi, ngaphansi kwesimo lesifanako, phakatsi kwamibili nalesihlanu imindeni letoba ngulengaphili njalo ngemnyaka wetigidzi yetinkhulungwane kepha, ngebukhona bemakhemikhali lamancane lakhona, singakhona kutfola lelinani kahle.

Nomakunjalo, lomubhalo ukhomba kutsi, esikhatsini lesitsite emandvulo, loku bekungulokungaphili kwe mass lapho khona liphesenthi lelitsite layoyonkhe lemphilo emhlabeni lanyamalala ngekushesha. Loku ngalesinye sikhatsi kubitwa tindzawo letinelilayini futsi tiluphawu ngekuchubeka kumatje nakumafossil, lapho khona lunye luhlobo lwemphilo leyakhiwe libuyiswa ngulenye. Lawa malayini avame kuba luphawu etincenyeni tematje etindzaweni letehlukene emhlabeni.

Kungaphili Kwe Mass

Njengoba setsembele kumbhalo we fossil kutsi sitfole emalayini, lenchubekela phambili yale mass lengaphili ibakhona ngemuva kwekukhokha lokuningi kwemphilo ngesikhatsi se Cambrian, kungaba iminyaka letigidzi tetinkhulungwane letimakhulu lasihlanu nemashumi lasihlanu iminyaka leyengcile (Ma).

Kusukela lapho, kubekhona tintfo letinkhulu letisihlanu temass lengaphili: Ekugcineni - ingucuko ye Ordovician (emakhulu lamane nemashumi lamane nakune Ma: kulahleka kwetilwane letimaphesenthi lamashumi lasiphohlongo), losasishiya Devonian (Emakhulu lamatsatfu nemashumi lasitfupha Ma: kulahleka kwetilwane letimaphesenthi lamashumi lasikhombisa nemfica), Kugcina-Permian (Emakhulu lamabili nemashumi lasihlanu Ma, kulahleka emaphesenthi lamashumi layimficanesihlanu - kungaphili kwemhlaba imass), Ekugcineni-Triassic (Emakhulu lamabili Ma, tilwane letilahlekile timasphesenthi lamashumi lasikhombisa nemfica) kantsi Kugcina - kwe Cretaceous (emashumi lasitfupha nesihlanu Ma, tilwane letimaphesenthi lamashumi lasikhombisa letilahlekile).

Bacwalingi besimanje bachubeka bafoselela kutsi kwanyalo sibambe sicinisile entfweni yalenye imass lengaphili, lephangisako leyake yabhalwa. Yasitakala ngekunakwa kwendzawo, loku lokubitwa nge Holocene lengaphili kungasho kutsi lokungaba yihhafu yetilwane temphilo emhlabeni titokufa kungakefiki iminyaka lelandzelako lelikhulu (ngekusho kwayinye kunesikhundla sesayensi).

Kususwa!

Tizatfu talemass lena tilukhuni kutisho. Nguyinye (Ekugcineni-Cretaceous, noma lilayini le K-T) selivele lichumanisiwe nesisindvo. Lalamanye anendzawo lencane, njengobe kute lokuhlanganako kusakhiwo lesitfoliwe noma sikhashane. Ngaphandle kwesisindvo, tintfo letivetiwe tifaka: tingucuko tesimo (lekufana ne ayisi legugako), tintfo letinkhulu tekubhedvuka (lekuphoyizina lendzawo lomoya), igamma-ray iyabhoma (lekufraya letintfo letiphilako ngetulu kwemhlaba) kanye neliplede le tectonic (lekungaletsa tigodzi kanyekanye kuphindze kuhlanganise tilwane temhlaba taphambilini tasemhlabeni, kusungula kuphutfuma ngekushesha kwetilwane letinsha).

Kutsatfwa kancane, nomakunjalo, leyo yinye yato iyinye ingabalelwa tonkhe letintfo temass, kanye nenhlangano yemafactor ibe siphetfo lesicinile. Noma ngusiphi simo, lucwalingo lukhombisa kutsi imass ivela ngendlela lesandingilizi, kambe kaningi njalo ngeminyaka lemashumi lamatsatfu kuya kumashumi lasitfupha etigidzi tetinkhulungwane. Kufanele kuphindvwe kutsatfwe kutsi njengoba asinalo luphawu lwe mass ngaphambi kwemakhulu lasihlanu eMa, akusho kutsi awazange avele.

Ngaphambi kwesikhatsi se Cambrian, imphilo yayikadze imcoka, kufaka tintfo letilula letifana neligciwane, brachiopods kanye ne trilobites. Leti tintfo letincane atiphili ngemuva kwefossil, futsi netinombolo tato tilukhuni kutitfola. Kwengetalapho, ematje kubuyela emuva ngetulu kweminyaka lemakhulu lasitfupha etigidzi tetinkhulungwane asayindlala, njengoba avame kubuyiswa ngalendlela ye tectonic. Loku kususaloluphawu lwencenye yelilayini lelingakhomba sikhatsi semonakalo emhlabeni. Hocisa kona ngekutsi, kube bekukhona kuhlangahlangana lokuningi kwemphilo Emhlabeni ngesikhatsi sesisindvo se Vredefort, ngabe tasuswa noma tawasheka!

Translated by Phindile Malotana