Enye ye izingqimba zomhlaba okutholakala ngezansi kwe-lithosphere yi- asthenosphere. Ungqimba olwakhiwe ikakhulu yidwala eliqinile elibhekene nengcindezi enkulu nokushisa okungaziphatha ngendlela yepulasitiki nokugeleza. Ibizwa ngokuthi ungqimba olubunjiwe ngenxa yokuthungwa nokwakheka kwayo. Lolu ungqimba lunezinhlelo eziningi ezisebenzayo olwazini lweplanethi yethu nasensimini ye-geology.
Kulesi sihloko sizokutshela konke odinga ukukwazi mayelana ne-asthenosphere.
Izici eziyinhloko
Amadwala atholakala e-asthenosphere anokuxinana okuphansi kunalawo atholakala ku- Ukuqhuma komhlaba. Lokhu kwenza amapuleti ama-tectonic we-lithosphere akwazi ukuhamba ebusweni bomhlaba sengathi ayantanta. Benza lokhu kuhamba ngamatshe akhuphukayo futhi bakwenza kancane kakhulu.
Enye indlela yokubiza i-asthenosphere ingubo ephezulu. Siyakhumbula ukuthi izingqimba zomhlaba zihlukaniswe zaba ziyi-3: uqweqwe, ingubo kanye nomgogodla. Lezo zindawo zeplanethi yonke lapho singathola khona i-asthenosphere eduze komhlaba zingaphansi kwezilwandle. Yilapho kunezindawo ezithile lapho kunokuncane okuncane kakhulu kwe-lithosphere. Ngenxa yalezi zindawo, ukwakheka nokwakheka kwe-asthenosphere kungaphenywa ngokujulile.
Ubukhulu obukhulu balolu ungqimba loMhlaba buba phakathi kwamamayela angama-62 kuye kuma-217. Izinga lokushisa kwalo alinakulinganiswa ngqo kepha lingaziwa ngophenyo olungaqondile. Kukholakala ukuthi ingaba phakathi kuka-300 no-500 degrees Celsius. Ngenxa yalokhu kushisa okukhulu kuba ungqimba we-ductile ngokuphelele. Okusho ukuthi, kunokuthungwa okungabunjwa njengokungathi sisebenzelana nento efana ne-putty.
Njengoba kushiwo ngaphambili, amadwala anokuxinana okuphansi futhi ancibilikile ngokwengxenye. Lokhu kungenxa yokuxubana kwamazinga okushisa aphezulu kanye nengcindezi enkulu abayibekezelelayo.
Imisinga ye-Convection ku-asthenosphere
Impela uzwile ngoJehova imibukiso ye-convection yengubo yomhlaba. Le misinga ye-convection izoba ngenxa yokuthi ukushisa okusuka kwenye indawo kudluliselwa kwenye indawo ngokuhamba koketshezi olufana nedwala elibunjiwe. Umsebenzi wokudlulisa ukushisa kwemisinga ye-convection yilezo ezihambisa imisinga yolwandle yomhlaba, isimo sezulu somkhathi, kanye nokwakheka komhlaba.
Ngenxa yokuhamba kwamazinga okushisa angaphakathi namatshe ancibilikisiwe, amapuleti ama-tectonic angahamba. Lesi yisona sizathu esikhulu esenza ukuthi amazwekazi angalungiswa endaweni eyodwa, kepha kunalokho anyakaze unyaka nonyaka yize engamabanga amancane. Eminyakeni ecishe ibe yizi-10.000 XNUMX amazwekazi asehambise ikhilomitha elilodwa kuphela. Kodwa-ke, uma sikuhlaziya lokhu ngezinga le- isikhathi sokuma komhlaba Singakuqinisekisa ukuthi, esikhathini esizayo sezigidi zeminyaka kusukela manje, kungenzeka ukuthi amapuleti ama-tectonic azokwakha kabusha lokho ngolunye usuku okwaziwa ngokuthi yi-super continent ebizwa ngePangea.
I-convection yehlukile ekuqhubeni ngoba okokugcina kungukudluliswa kokushisa phakathi kwezinto ezixhumene ngqo. Okubangela imisinga ye-convection yengubo ngamatshe ancibilikile ekujuleni ezisakazwa ngenxa yezinguquko ekushiseni. Lawa matshe asesimweni esiwuketshezi oluningi ukuze aziphathe njengolunye uketshezi. Zivuka phansi kwesembatho futhi ngemuva kokuba zishise futhi zingabi maningi ngenxa yokushisa kwengqikithi yoMhlaba.
Njengoba idwala lilahlekelwa ukushisa futhi lingena koqweqwe lomhlaba, liya libanda ngokwengeziwe futhi, ngenxa yalokho, liminyene ngokwengeziwe. Ngale ndlela iphinde yehle iye ngakuyo i-nucleus. Kukholakala ukuthi lokhu kusakazwa okungapheli kwedwala elincibilikile yikhona okunomthelela ngqo ekwakheni izintaba-mlilo, ukuzamazama komhlaba kanye nokuhamba kwamazwekazi.
Ijubane lemisinga yokudlulisa nokubaluleka kwe-asthenosphere
Ijubane lapho imisinga ye-convection yengubo iya khona imvamisa ingama-20mm / ngonyaka, ngakho-ke akunakuthathwa njengenani elibonakalayo. Lokhu kudidizela kuphezulu engubeni ephezulu kune-convection eseduze nengaphakathi. Umjikelezo owodwa we-convection ku-asthenosphere ungathatha cishe iminyaka eyizigidi ezingama-50. Ngakho-ke, sishilo ngaphambili ukubaluleka kokuhlaziya zonke lezi zinqubo ngesikhathi sokwakheka komhlaba. Umjikelezo ojulile we-convection engubeni ungathatha cishe iminyaka eyizigidi ezingama-200.
Mayelana nokubaluleka kwe-asthenosphere, singasho ukuthi ithonya umoya ngokuhamba kolwandle kanye namacwecwe ezwekazi. Ngasikhathi sinye, isikhundla samazwekazi namachibi olwandle nakho kuguqula indlela umoya nesimo sezulu ezihamba ngayo emhlabeni. Ukube bekungengenxa yale mizila ye-convection, ukunyakaza esishilo njengokukhukhuka kwezwekazi ngabe akukho. Inesibopho sokwakhiwa kwezintaba, ukuqhuma kwezintaba-mlilo nokuzamazama komhlaba.
Yize le micimbi ingathathwa njengokubi esikhathini esifushane, kunezinzuzo eziningi esikalini sesikhathi sokuma komhlaba ezifana ukwakheka kwempilo entsha yezitshalo, ukwakhiwa kwezindawo ezintsha zemvelo kanye nokuvuselelwa kokuzivumelanisa nezidalwa eziphilayo. Imithelela ehlukahlukene i-asthenosphere enayo emhlabeni iyasebenza ukuze impilo yenzeke ngokuhlukahluka okukhulu.
Ngaphezu kwalokho, i-asthenosphere nayo ibhekene nokwakhiwa koqweqwe lomhlaba omusha. Lezi zindawo zitholakala emaphethelweni olwandle lapho i-convection yenza le asthenosphere inyukele phezulu. Njengoba okokuncibilikisa okuyingxenye kuqhuma, kuyaphola, kwazisa uqweqwe olusha.
Ngiyethemba ukuthi ngalolu lwazi ungafunda kabanzi nge-asthenosphere.