Uma ufunda i-geology uzwile ngokuqinisekile ngakho umkhawulo wolwandle. Umqondo wayo uchazwa ngendlela ethile eyinkimbinkimbi. Kungokwesisekelo semibono yokwakheka komhlaba njengama-plate tectonics. Yile mibono esekela umsuka wemifula yolwandle.
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 ukuhamba kwamacwecwe ama-tectonic akha uqweqwe lomhlaba. Iziduli ezinqwabelana emigqeni yezintaba ezingaphansi kolwandle zijiyile okungenani izikhathi eziyishumi kunalezo ezisenkabeni yezwe. Lokhu kuphakamisa umbono we-geosyncline. Lona ngumbono othi umkhumbi wezwekazi uyakhula ngenxa yokuqoqeka okuqhubekayo nokukhulu okuvela kuma-geosyncline asendulo futhi agoqiwe. Ngokuhamba kwesikhathi ziye zaqina futhi zahlanganiswa zaba amapuleti amanje.
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. Ekuqhekekeni kukhona ukuzamazama komhlaba okungajulile nokuqhuma kwentaba-mlilo lapho kukhishwa khona inani elikhulu le-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.
Isigaxa esisha sasolwandle esakhiwe emaphethelweni ngengxenye yengubo engenhla yengubo ephezulu kanye noqweqwe lwakha i-lithosphere. Zonke izikhungo zasolwandle zinwebela emaphethelweni olwandle oluphakathi. Ngakho-ke, izici eziningi ezitholakala kulezi zindawo zehlukile.
Ziyisihloko sezifundo eziningi. Ukuze wazi ngokujula ukwakheka nokuvela kwamagquma, kufundwa ama-basaltic lavas. Lawa lavas angcwatshwa kancane kancane yizinsalela ezifakwe kuwo wonke umhlaba. Ezimweni eziningi, ukugeleza kokushisa kunamandla kakhulu ngaphakathi kwemifantu emhlabeni wonke.
Kujwayelekile kakhulu ukuthi ukuzamazama komhlaba kwenzeke emaphethelweni futhi, ngaphezu kwakho konke, emaphutheni wenguquko. La maphutha ajoyina izingxenye zesinxephezelo sezinxephezelo. Ukuzamazama komhlaba okwenzeka kulezi zindawo kucwaningwa ngokujulile ukuthola ulwazi mayelana nengaphakathi 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 beqolo bungabalwa ngokususelwa kunani lokusabalalisa. Imvamisa zikhula cishe ngama-160 mm ngonyaka, okungasho lutho ngesilinganiso somuntu. Kodwa-ke, esikalini se-geological kuyabonakala. Izinombolo ezihamba kancane yilezo zihlakazeka okuncane okungama-50 mm ngonyaka kanti ezisheshayo zifinyelela ku-160 mm.
Lezo ezinweba kancane kancane zinokugqashuka kanti ezisheshayo azinazo. Kancane kancane imisele eklebhukile inesimo sendawo esingajwayelekile ezinhlangothini zayo, kuyilapho imigwaqo esabalala ngokushesha inezikhala ezibushelelezi kakhulu.
Njengoba ukwazi ukubona, udonga lwasolwandle luyinkimbinkimbi kakhulu kunokuba lubonakala. Amandla ayo achazwa ngomsebenzi womhlaba ohamba ngokuqhubekayo.
Kuhle kakhulu!