Uma ufunda i-geology uzwile ngokuqinisekile ngakho umkhawulo wolwandle. Umqondo wayo uchazwa esimweni esiyinkimbinkimbi. Kungokwemibono yokwakheka komhlaba njenge Amapuleti eTectonic. Lena imibono esekela umsuka wamagquma amaphakathi nolwandle.
Futhi ukuthi udonga lwasolwandle aluyilutho ngaphandle kohambo lwentaba olungaphansi kwamanzi olwenziwe ukufuduswa kwamapuleti e-tectonic. Ngabe ufuna ukwazi imvelaphi, izici nezinhlobo zemikhawulo yolwandle ekhona emhlabeni wethu?
Izici nemvelaphi yokhalo lwasolwandle
Lapho kwakhiwa imimango eminingana yolwandle ngaphansi kwezilwandle, izinhlelo zezintaba eziyiqiniso zakhiwa ngaphansi kolwandle. Izintaba ezinkulu kakhulu ezingaphansi kwamanzi emhlabeni ubude besikhathi esingamakhilomitha angama-60.000. Amaphethelo olwandle ahlukaniswa ngamachibi olwandle.
Umsuka wayo unikezwa ukunyakaza kwamapuleti e-tectonic akha i- Ukuqhuma komhlaba. Izinsalela ezinqwabelana ezintabeni ezingaphansi kwamanzi zijiya ngokuphindwe kashumi kunezakuleli zwekazi. Lokhu kudala i-geosynclinal theory. Lona umbono othi i-continental crust ikhula ngenxa yokuqoqwa okuqhubekayo nokukhulu okuvela ku-geosynclines yasendulo kanye nokugoqa. Ngokuhamba kwesikhathi baye baqina futhi bahlanganisa amapuleti amanje.
Ucwaningo lwe amagquma aphakathi nolwandle Kubalulekile ukuqonda ithonya layo ekukhululekeni komhlaba.
Isakhiwo se-dorsal
Ubuningi balezi zintaba ezingaphansi kwamanzi bungafinyelela linganisa phakathi kwamamitha ayi-2000 kanye nama-3000 ukuphakama. Imvamisa zinendawo emangelengele, enemithambeka ebanzi nemikhawulo evezwe kakhulu. Lapho lawa maqaqa enemfantu ejulile kubizwa ngokuthi isigodi esicwilayo noma ukuqhekeka. Emifantwini eminingi kukhiqizwa ukuzamazama komhlaba okungajulile nokuqhuma kwentaba-mlilo lapho kukhishwa khona inqwaba ye-basalt.
Ama-basalts enza ukwakheka kolwandle lonke. Ezinhlangothini zomgogodla, ukushuba koqweqwe lwentaba-mlilo nobukhulu beziduli kuyanda. Kukhona nezintaba-mlilo ezingaphansi kwamanzi, kodwa zihlakazekile futhi zinesizungu. Akudingeki ukuthi ube sengozini.
Amaphethelo wemikhawulo angahle asuswe kamuva ezigabeni ezibanzi ezihambelana nezindawo zokuphuka. Lapho sihlangana nomngcele ophakathi kwamapuleti amabili, udaka olushisayo noluncibilikile lukhuphukela phezulu. Lapho selufikile, luyaphola futhi luqine ngenkathi uqweqwe oludala kakhulu luhlukana ezinhlangothini zombili zomqolo.
Lokhu kuhlala kuskrola. Ubufakazi balokhu ukuthi ukuhamba kwemifula yolwandle kukalwe ezindaweni ezithile e-Atlantic. Ukuhanjiswa okungafika kumasentimitha amabili ngonyaka kubhaliwe. Ngakolunye uhlangothi, empumalanga yePacific, izilinganiso zokuhamba kanye idatha ye-14 cm ngonyaka itholakele. Lokhu kusho ukuthi amaphethelo olwandle oluphakathi awahambi yonke indawo ngejubane elifanayo. Ushintsho kumthamo ocwilisiwe wamagquma kudala ushintsho oluncane olwandle ngezinga le-geological. Uma sibhekisa esikalini sokuma komhlaba, sikhuluma ngezinkulungwane zeminyaka.
Ukuba yinkimbinkimbi kogu lolwandle
Emaphethelweni wezintaba singathola imifantu ye-hydrothermal. Umusi onenqwaba yamaminerali uyaphuma kuwo uwenze ezingeni lokushisa lama-350 degrees. Lapho kufakwa amaminerali, enza kanjalo ngokwakha izakhiwo ezifana nekholomu ezinokuqukethwe okuyisisekelo okungamakhemikhali ensimbi e-sulfide. Lawa ma-sulfide ayakwazi ukuxhasa amakoloni ezilwane angavamile. Lezi zinhlanganisela ziyingxenye ebalulekile ekusebenzeni kwemvelo yasolwandle. Ngenxa yalokhu, ukwakheka kwamanzi kuzinze ngokwengeziwe.
I-oceanic crust entsha ekhiqizwa emagqumeni enengxenye yengubo engaphezulu futhi uqweqwe olungaphezulu lwakha lithosphere. Zonke izikhungo zasolwandle zinwebela emaphethelweni olwandle oluphakathi. Ngakho-ke, izici eziningi ezitholakala kulezi zindawo zehlukile.
Ziyisifundo sezifundo eziningi. Ukuze uthole ukuqonda okujulile kokubunjwa nokuziphendukela kwemvelo, ama-basaltic lavas ayafundwa. Ingabe uyageza Zigqitshwa kancane kancane yizinsalela ezibekwe phezu kwendawo yonke. Ezimweni eziningi, ukugeleza kokushisa kunamandla ngaphakathi kwamagquma kunasemhlabeni wonke.
Kuvame kakhulu ukuthi ukuzamazama komhlaba kwenzeke eduze kwamagquma futhi, ngaphezu kwakho konke, ku- amaphutha enguquko. Lawa maphutha ajoyina izingxenye ze-offset ridge. Ukuzamazama komhlaba okwenzeka kulezi zindawo kufundwa ngokujula ukuze kuqondwe ingaphakathi loMhlaba.
Ukuhlakazeka kwe-Dorsal
Ngakolunye uhlangothi, kunobudlelwano obuqinile phakathi kokujula okukhona igebe lasolwandle nobudala balo. Ngokuvamile, kukhonjisiwe ukuthi ukujula kolwandle kuyalingana nempande eyisikwele yeminyaka yoqweqwe. Le mbono isuselwe ebudlelwaneni obuphakathi kweminyaka yobudala nokuncipha okushisayo koqweqwe lwasolwandle.
Ukupholisa okuningi kokwakhiwa kwamagquma olwandle kwenzeka eminyakeni eyizigidi ezingama-80 edlule. Ngaleso sikhathi, ukujula kolwandle kwakungu-5 km kuphela. Njengamanje, yaziwa ngaphezu kwamamitha ayi-10.000 XNUMX ukujula. Ngoba lokhu kupholisa kungumsebenzi wobudala, imigwaqo esabalala kancane, efana neMid-Atlantic Ridge, incane kunamagquma akhula ngokushesha, njenge-East Pacific Ridge.
Ububanzi be-ridge bungabalwa ngokuya ngesilinganiso sokuhlakazeka. Ngokuvamile zikhula cishe ngo-160 mm ngonyaka, okuyinto enganakwa esikalini somuntu. Nokho, ngesilinganiso sokwakheka komhlaba kuyaphawuleka. Ama-dorals anensa kakhulu yilawo zihlakazeka okuncane okungama-50 mm ngonyaka kanti ezisheshayo zifinyelela ku-160 mm.
Ezikhula kancane zinomfantu, kanti ezishesha kakhulu azinawo. Ama-ridges asakazeka kancane anesimo sendawo esingavamile emaceleni awo, kuyilapho ama-ridges asakazeka ngokushesha anezinhlangothi ezibushelelezi.
Njengoba ubona, umgwaqo ophakathi nolwandle uyinkimbinkimbi kunalokho okubonakala. I-dynamics yayo ichazwa yi- umsebenzi wasemhlabeni enyakaza njalo.
