Ukwakheka Kweziqhingi

“IHAWAII.” IziQhingi zaseHawaii zenza umuntu acabange ngepharadesi, amabhishi afudumele nemimoya epholile ehelezayo. Kodwa ubuqaphela yini ukuthi lezi ziqhingi zisemajukujukwini kangakanani? Uma ufuna iHawaii ebalazweni, uyothola lezi ziqhingi zisenkabeni yeNorth Pacific Ocean—zikude nezwe! Ngakho, ungase uzibuze, ‘Kwenzeka kanjani ukuba lezi ziqhingi zibe kule ndawo? Ingabe ososayensi bakholelwa ukuthi kuyoba neziqhingi ezengeziwe esikhathini esizayo? Lezi ziqhingi zisitshelani ngalo mhlaba esihamba phezu kwawo?’

Iqoqo Leziqhingi ZaseHawaii

Abantu abaningi abavakashela eHawaii bajwayelene neqoqo leziqhingi ezingu-8 ezisuka enyakatho-ntshonalanga ziye eningizimu-mpumalanga, ezinkulu kuzo okuyiKauai, i-Oahu, iMolokai, iLanai, iMaui neHawaii. Isiqhingi esincane iNiihau singasentshonalanga yeKauai, kanti iKahoolawe iseningizimu-ntshonalanga yeMaui. Isiqhingi saseHawaii, esibizwa nangokuthi isiQhingi Esikhulu, sinobukhulu obungaphezu kwamakhilomitha-skwele angu-10 000, kanti esincane iKahoolawe singaba nje amakhilomitha-skwele angu-117. Ngaphezu kwalokho, leli qoqo leziqhingi lihlanganisa nezinye iziqhingi ezincane kakhulu ezingu-124, ezidlulela ngisho nakude enyakatho-ntshonalanga. Isiqhingi iMidway, esingasemaphethelweni aleli qoqo leziqhingi ngasenyakatho-ntshonalanga, siqhele ngamakhilomitha angaba ngu-2500 ukusuka esiQhingini Esikhulu! Iziqhingi ezincane, ngokuyinhloko ezakhiwe ama-coral nesihlabathi, zihlanganisa ibanga elingamakhilomitha-skwele angu-8 kuphela. Ngokufanele, abanye basebenzisa amagama athi Iqoqo Leziqhingi ZaseHawaii bebhekisela kuzo zonke lezi ziqhingi.

Uma sicabangela ukuthi lezi ziqhingi neziqhingana ziphezu komhlaba obanzi ophakeme ngamamitha angaphezu kwangu-4000 ukusuka ekujuleni kolwandle, siyaqaphela ukuthi lezi ziqhingi zimane ziyiziqongo zezintaba eziphakeme kakhulu ezivele ngaphezu kwamanzi. Eqinisweni, uma zilinganiswa ubude kusuka lapho siqala khona ekujuleni kolwandle, iMauna Kea neMauna Loa esiqhingini saseHawaii zingamamitha angaba ngu-10 000 ukuphakama. Ngakho, ngomqondo othile ziyizintaba eziphakeme kunazo zonke emhlabeni!

Ukwakheka Kwesiqhingi

Ake siqhubeke sihlola isiqhingi saseHawaii. Izazi zokuma komhlaba ziye zathola ukuthi isiQhingi Esikhulu sinezintaba-mlilo ezinhlanu ezinkulu ezihlangene. Izivakashi eziningi zijwayelene nezintathu ezinkulu—iMauna Kea, okuthiwa ayisaqhumi futhi ephakeme kunazo zonke eHawaii, engamamitha angu-4205 ngaphezu kogu lolwandle; iMauna Loa, engamamitha angu-4169 futhi eyintaba-mlilo enkulu kunazo zonke eHawaii; neKilauea, okuyintaba-mlilo encane kunazo zonke engaseningizimu yesiqhingi. Ngaphezu kwalokho, intaba-mlilo iKohala isemngceleni walesi siqhingi ongasenyakatho-ntshonalanga, kanti iHualalai yengamele ugu lwaseKona.

Intaba-mlilo ngayinye yakhula ngenxa yokuchitheka nokunqwabelana kodaka olushisayo izikhathi eziyizinkulungwane. Ukuqhuma kuqala ngaphansi kwamanzi, lapho udaka olushisayo lusheshe luphole khona, lwakhe izingqimba ezifana nolimi okuthi lapho sezinqwabelene zifane nemicamelo eminingi. Lapho intaba-mlilo ekhulayo ivela ngaphezu kwamanzi, udaka oluphuma kuyo luyashintsha lubukeke ngenye indlela. Izazi zezintaba-mlilo zisebenzisa igama lesiHawaii elithi “pahoehoe” uma zichaza udaka olubushelelezi, olunsongensonge noluhlangene kanye nelithi “aa” ukuchaza udaka olumahhadla noluyimvithi. Intaba-mlilo iba intaba endlalekile, enomthambeka efana namahawu ayephathwa amasosha aseRoma yasendulo. Kuvuleka imigodi emikhulu esiqongweni sentaba-mlilo lapho i-magma, noma amadwala ancibilikile, iqhuma noma ibuyela emigodini eseduze nomlomo wentaba. Futhi, indawo lapho la madwala ephuma khona ngaphakathi kwentaba-mlilo inomfutho. Lo mfutho usunduzela ingxenye yentaba-mlilo ngasolwandle, okuvula imifantu eminingi emikhulu. Ekugcineni, njengasendabeni yeMauna Kea, ukuqhuma kongqimba lwentaba-mlilo kuba kukhulu, kuphume inqwaba yamalahle aqoqana phezulu.

IMauna Loa neKilauea ziye zabonakala ziphakathi kwezintaba-mlilo eziqhuma kakhulu kunazo zonke emhlabeni. Ukulandisa okungokomlando kwabantu baseHawaii, izithunywa zevangeli, ososayensi nabanye kubonisa ukuthi iMauna Loa iye yaqhuma izikhathi ezingu-48 kusukela ngo-1832, kanti iKilauea iye yaqhuma izikhathi ezingaphezu kwezingu-70 kusukela ngo-1790. Lokhu kuqhuma kuye kwathatha amahora ambalwa noma iminyaka eminingi. Okuyingqopha-mlando kwakuyichibi lodaka olushisayo emlonyeni weHalemaumau eKilauea, eyaqhuma cishe inganqamuki kusukela ekuqaleni kwawo-1800 kwaze kwaba ngo-1924. Okwamanje, iKilauea ibilokhu iqhuma kusukela ngo-January 1983, ngezinye izikhathi ikhipha umlilo omkhulu ophethukayo nemifula yodaka olushisayo egelezela olwandle.

Ngenxa yodaka lwazo olushisayo olugelezayo, ukuqhuma kwezintaba-mlilo eziningi eHawaii kuthulile noma akunamandla kakhulu. Nokho, ngezikhathi ezingavamile, amanzi angaphansi axubana namadwala ancibilikile, bese kuba ukuqhuma okukhulu okukhipha isitimu. Ngo-1790, ukuqhuma okunjalo kwabulala abantu abangaba ngu-80 lapho iqembu lamasosha omdabu namalungu emikhaya yawo lisitshekelwa isisi esishisayo namalahle avuthayo ayephuma eKilauea.

Iziqhingi Ezihambayo

Umlando olotshiwe kule minyaka engu-200 edlule ubonisa ukuthi yiziqhingi ezimbili kuphela ezisemaphethelweni eningizimu-mpumalanga, iHawaii neMaui, ebezilokhu ziqhuma. Lesi simo esididayo sashukumisa ososayensi ukuba baqhubeke behlola umlando wamadwala aleli qoqo leziqhingi. Ngaphakathi kodaka olushisayo kunengcosana ye-potassium ekhipha imisebe kanye nomkhiqizo wayo osuvundile, i-argon, ababengayilinganisa ezikhungweni zocwaningo ukuze bathole isilinganiso sobudala bamadwala. Lolo cwaningo lwembula ukuguga kwalo lonke leliQoqo Leziqhingi ZaseHawaii ngasenyakatho-ntshonalanga osekuyizigidi zeminyaka kwenzeka.

Njengoba ukuqhuma kwezintaba-mlilo zaseHawaii bekwenzeka kakhulu engxenyeni eseningizimu-mpumalanga yalezi ziqhingi, ingabe lokhu kusho ukuthi umthombo wamadwala ancibilikile ongaphansi kwazo nawo ubulokhu uhamba? Eqinisweni, izazi zokuma komhlaba ziye zathola ukuthi umthombo walolu daka, abawubiza ngokuthi i-hot spot, umi ndawonye. Kunalokho, iphansi lePacific Ocean belilokhu lihamba phezu kwale hot spot, lidedisela lezi ziqhingi eziyizintaba-mlilo kude ne-hot spot, njengamadwala amaningi phezu kwebhande elihambayo elithwala impahla. Lokhu kuhamba okufanayo kwenza iphansi lePacific ligudlane namazwekazi angomakhelwane nezinye izindawo ezingaphansi kolwandle, okubangela ukuzamazama komhlaba okukhulu okwenzeka endaweni yePacific Rim. Uma uhlala eHawaii, umuzi wakho uye washenxa ngamasentimitha angu-7,5 ngasenyakatho-ntshonalanga kusukela ngonyaka odlule!

Ososayensi basikisela ukuthi amanye ama-hot spot anjengaleyo engaphansi kweHawaii abangela izintaba-mlilo eziningi emhlabeni wonke, ezweni nasolwandle. Amaningi ala ma-hot spot abonisa nokuthi kunokuqhuma okudlulela kwezinye izindawo, okusho ukuthi ungqimba lwenhlabathi kungenzeka beluhamba nalapho uhlala khona.

Ukwakheka Kweziqhingi Ezintsha . . .

Njengoba kuye kwathatha amakhulu ezinkulungwane zeminyaka ukwakha izintaba-mlilo ezinkulu ezisesiQhingini Esikhulu, singalindela ukuthi lesi siqhingi besilokhu sidedela kude ne-hot spot phakathi naleso sikhathi. Khona-ke, kufanele kwakheke izintaba-mlilo neziqhingi ezintsha ngaphezu kwe-hot spot njengoba idlula ezindaweni ezingenalutho ezisekujuleni kolwandle. Ingabe ikhona intaba-mlilo ewumlandeli wezintaba-mlilo zesiQhingi Esikhulu esibonakele kakade?

Yebo. Intaba eqhumayo engaphansi kwamanzi, iLoihi, iyakhula eningizimu yesiqhingi saseHawaii. Nokho, ungalindeli ukuba ivele ngaphezu kolwandle maduzane. Kusadingeka iphakame ngamanye amamitha angu-900, okungase kuthathe amashumi ezinkulungwane zeminyaka.

 . . .Nokushabalala Kweziqhingi Ezindala

Izintaba-mlilo ezinkulu nodaka olumahhadla okwakha iziQhingi zaseHawaii kubonakala sengathi akunakucwila futhi olwandle. Kodwa iziqhingi ezincane kanye nezintaba ezacwila enyakatho-ntshonalanga yeHawaii zibonisa okuhlukile. Ngokwesibonelo, isihlabathi nezixhobo zama-coral zeziqhingi zaseMidway naseKure kuphezu kwezintaba-mlilo ezinkulu ezineziqongo ezingaphansi kakhulu kogu lolwandle. Kungani iziqhingi zezintaba-mlilo zinyamalala?

Lezi ziqhingi ziguguleka kancane kancane ngenxa yemisele, amagagasi nezinye izinto. Lezi ziqhingi futhi ziyazidilikela njengoba zizika ekujuleni kolwandle. Amawa amakhulu agudla ezinye iziqhingi abonisa ukuthi kunenye inqubo eshabalalisa iziqhingi zezintaba-mlilo—ukudilika kwenhlabathi. Imifanekiso ye-sonar yezindawo ezigudla lezi ziqhingi yembula ukudilika kwenhlabathi okukhulu okushona phansi ekujuleni kolwandle.

Ukusebenza Kwe-hot spot

Esiqhingini saseHawaii, izivakashi eziya eHawaii Volcanoes National Park zingazibonela ngawazo ukuma kwezwe okushintshashintshayo okubangelwa ama-hot spot ezintaba-mlilo. Ososayensi baseHawaiian Volcano Observatory, engasemlonyeni weKilauea, bahlola ukuqhuma okuqhubekayo nokusongelayo. Ukuhlola kwabo kuye kwandisa ukukhanya okukhulu ngendlela izintaba-mlilo ezisebenza ngayo nendlela ungqimba lomhlaba oluye lwagudluka ngayo. Ngokumangala, singabona ukuthi amandla omhlaba amakhulu aye abumba futhi alolonga iQoqo Leziqhingi ZaseHawaii—leli qoqo elihle leziqhingi elisenkabeni yePacific Ocean.

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(Ukuze ubone ukuthi indaba ihlelwe kanjani, bheka encwadini)

IziQhingi zaseHawaii

Niihau

Kauai

Oahu

Molokai

Lanai

Maui

Kahoolawe

Hawaii

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Mountain High Maps® Copyright © 1997 Digital Wisdom, Inc.

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Uhide lwezindawo ezinomlilo ophethukayo emfantwini weKilauea ongasempumalanga

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Ukuqhuma kweKilauea

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Volcanoes: Dept. of Interior, National Park Service

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Umfula wodaka olushisayo eMauna Loa

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Umlilo oqubuka eMauna Loa

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Top left and bottom right: Dept. of Interior, National Park Service

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Umlilo ophethukayo eKilauea

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U.S. Geological Survey

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Ichibi lodaka olushisayo eKilauea

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Top left and bottom right: Dept. of Interior, National Park Service