Iyini i-Pangea Theory?
I-Pangea Theory iyinkolelo-mbono eyisisekelo kwezesayensi ye-geology kanye nomhlaba echaza ukwakheka kwamazwekazi amakhulu ayekhona esikhathini esidlule. Ngokwalo mbono, wonke amazwekazi omhlaba anamuhla ake ahlanganiswa, akha izwekazi elilodwa elikhulu elibizwa ngokuthi i-Pangea. Igama elithi "Pangaea" ngokwalo livela esiGrekini sasendulo, lapho elithi "Pan" lisho konke, kanti elithi "Gea" lisho umhlaba noma umhlaba, ngakho-ke i-Pangea ngokwezwi nezwi isho "wonke umhlaba."
Umsuka Wethiyori
Ithiyori yePangea yaqala ukwethulwa yisazi sezulu saseJalimane kanye nesazi se-geophysicist, u-Alfred Wegener ngo-1912. UWegener, kumbono wakhe owaziwa ngokuthi yithiyori ethi “Continental Drift”, wathi eminyakeni ecishe ibe yizigidi ezingu-300 edlule, wonke amazwekazi akhona namuhla ake ahlanganiswa kwelinye izwekazi elikhulu ngaphambi kokuba ekugcineni ahlukane futhi athuthele ezindaweni zawo zamanje.
UWegener wasebenzisa izinhlobo ezahlukene zobufakazi ukusekela umbono wakhe. Esinye sezingcezu eziyinhloko zobufakazi kwakuwukufana ogwini lolwandle lwaseNtshonalanga Afrika nasempumalanga yeNingizimu Melika, okwakubukeka njengezingcezu zephazili ezingahlanganiswa ndawonye. Wathola nokufana ekwakhekeni kwe-geological kuzo zombili izinhlangothi zoLwandlekazi i-Atlantic. Amaphethini okusatshalaliswa kwezinsalela zezitshalo nezilwane nawo anikeze ukwesekwa okwengeziwe kombono kaWegener. Isibonelo, izinsalela zezitshalo zohlobo lwe-Glossopteris zatholakala emazwekazini manje ahlukaniswe ulwandle olukhulu.
Ubufakazi Obengeziwe kanye Nokuthuthukiswa Kwethiyori
Ngemva kokufa kukaWegener ngo-1930, ubufakazi obengeziwe kanye nokuthuthukiswa kwenkolelo-mbono ye -plate tectonics kwanikeza incazelo eningiliziwe yokuthi i-continental drift isebenza kanjani. Ngawo-1960, inkolelo-mbono ye-plate tectonics ekugcineni yamukelwa kabanzi emphakathini wesayensi futhi yanikeza uhlaka lokuqonda izenzakalo eziyinkimbinkimbi kakhulu eMhlabeni.
Ngokusho kwenkolelo-mbono ye-plate tectonics , ungqimba loMhlaba luqukethe amapuleti amaningi amakhulu e-tectonic antanta phezu kongqimba olumanzi kakhulu olubizwa ngokuthi i-asthenosphere. Ukunyakaza kwala mapuleti kubangelwa yi-convection currents e-mantle ngaphansi kongqimba. Ukusebenzisana phakathi kwala mapuleti kubangela izenzakalo eziningi ze-geological, okuhlanganisa ukuzamazama komhlaba, izintaba-mlilo, ukwakheka kwezintaba, kanye, nokuhlukana nokuhamba kwamazwekazi.
Inqubo Yokwakheka Nokuhlukaniswa KwePangea
I-Pangea ayizange yakheke yonke ngesikhathi esisodwa, kodwa yadalwa ngochungechunge lwezinqubo zokuhlangana phakathi nesikhathi eside se-geologic. Amazwekazi amaningana asendulo asondelana futhi ahlangana ngokuhamba kwesikhathi ngaphambi kokuba ekugcineni akhe i-supercontinent Pangea eminyakeni engaba yizigidi ezingu-335 edlule ngesikhathi seCarboniferous.
I-Pangaea yaqala ukuqhekeka eminyakeni engaba yizigidi ezingu-175 eyedlule ngesikhathi sokuqala kweJurassic. Ukuqhekeka kwayo kwaqala ukudala amazwekazi amabili amakhulu amakhulu: iLaurasia enyakatho neGondwana eningizimu. ILaurasia kamuva yaqhekeka yaba iNyakatho Melika, iYurophu, kanye neNyakatho ye-Asia, kwathi iGondwana yahlukana yaba iNingizimu Melika, i-Afrika, i-Antarctica, i-Australia, kanye ne-Indian subcontinent. Lokhu kuqhubeka kuze kube namuhla futhi kuye kwabumba isimo samazwekazi njengoba siwazi namuhla.
Umthelela kanye Nethonya Le-Pangea
Ukwakheka nokuqhekeka kwePangaea kwaba nomthelela omkhulu esimweni sezulu, impilo, kanye nokwakheka komhlaba weplanethi yethu. Lapho iPangaea isungulwa, yayizungezwe ulwandle olulodwa olubizwa ngokuthi iPanthalassa. Ububanzi bezwekazi babangela ukuthi ingaphakathi lalo libe yisomiso futhi libhekane nezimo zezulu ezibucayi kakhulu zezwekazi. Lokhu kushintsha kwesimo sezulu kungenzeka kube nomthelela omkhulu emaphethini okuziphendukela kwemvelo kanye nokusabalala kwezinto eziphilayo ezaziphila ngaleso sikhathi.
Ukuhlukana kwePangea kwaholela nasezindleleni ezahlukene zokuziphendukela kwemvelo emhlabeni wonke. Njengoba amazwekazi ehlukana, izinhlobo zezinto eziphilayo zahlukaniswa futhi zavela ngokwazo, okuchaza ukuthi kungani sibona ukuhlukahluka okuningi kwezinto eziphilayo kuwo wonke amazwekazi namuhla. Isibonelo, izilwane zase-Australia zihluke kakhulu kwezase-Asia noma e-Afrika ngoba i-Australia yahlukaniswa ulwandle isikhathi eside.
Imibuzo Nezimpikiswano
Njengoba ukubonwa kanye nezindlela zesayensi kuye kwavela, inkolelo-mbono yePangea kanye ne-plate tectonics ithole ukwesekwa okubanzi emphakathini wesayensi. Kodwa-ke, kusenemibuzo eminingana kanye nezimpikiswano, njengokuthi imisinga ye-convection e- mantle yoMhlaba ithonya kanjani ukunyakaza kwe-plate, nokuthi amazwekazi amadala angaphambi kwePangea, njengeRodinia neNuna, athonya kanjani ukuvela koqweqwe lomhlaba kanye ne-mantle yoMhlaba.
Abanye ochwepheshe bazama nokuqonda iphethini yokujikeleza kokwakheka kwezwekazi elikhulu ngokuhamba kwesikhathi. Isibonelo, enye inkolelo-mbono iphakamisa ukuthi amazwekazi amakhulu angakheka futhi aqhekeke okungenani njalo eminyakeni eyizigidi ezingu-500-700. Uma lokhu kuyiqiniso, singase sibe phakathi komjikelezo wokwakheka kwezwekazi elikhulu esikhathini esizayo.
Isiphetho
Ithiyori yePangea inikeza ukuqonda okujulile ngomlando we-geological kanye nokuguquguquka kwamazwekazi oMhlaba. Ukuqonda lo mlando kusenza siqonde ukuthi uMhlaba wavela kanjani waba yiplanethi esiyaziyo namuhla, enazo zonke izinhlobo, izimo zezulu, kanye nezinto eziphilayo ezihlala kuyo.
Kusukela u-Alfred Wegener ethula lo mbono eminyakeni engaphezu kwekhulu edlule, ucwaningo luye lwaqhubeka, lunikeza ukuqonda okucacile nokuningiliziwe. Ngokuthuthuka kobuchwepheshe obusha kanye nezindlela, cishe sizoqhubeka nokuthola ulwazi olwengeziwe ngomlando woMhlaba kanye mhlawumbe nokuma kwawo esikhathini esizayo.
