{"id":36398,"date":"2019-08-30T03:23:42","date_gmt":"2019-08-30T00:23:42","guid":{"rendered":"https:\/\/bilimvegelecek.com.tr\/?p=36398"},"modified":"2019-08-27T16:28:27","modified_gmt":"2019-08-27T13:28:27","slug":"volkan-ve-volkanizma-nedir-nasil-olusur-urunleri-nelerdir","status":"publish","type":"post","link":"https:\/\/bilimvegelecek.com.tr\/index.php\/2019\/08\/30\/volkan-ve-volkanizma-nedir-nasil-olusur-urunleri-nelerdir","title":{"rendered":"Volkan ve volkanizma nedir? Nas\u0131l olu\u015fur, \u00fcr\u00fcnleri nelerdir?"},"content":{"rendered":"

Volkanlar \u00e7e\u015fitli olmalar\u0131na ra\u011fmen, tan\u0131mlar\u0131 \u00e7ok basittir. Volkan, magma k\u00f6kenli lavlar\u0131n d\u0131\u015far\u0131ya \u00e7\u0131kmas\u0131n\u0131 sa\u011flayan, yerkabu\u011funda olu\u015fmu\u015f bir k\u0131r\u0131k ya da a\u00e7\u0131kl\u0131kt\u0131r. Volkan kelimesinin k\u00f6keni Sicilya dilinde \u201cVurcanu\u201ddur. Vulcano (Roma dilinde) Tirheniyen Denizi\u2019nde k\u00fc\u00e7\u00fck bir volkanik adad\u0131r ve Sicilya\u2019n\u0131n 25 km kuzeyinde bulunur. Di\u011fer taraftan Vulkan, Roma\u2019n\u0131n Ate\u015f Tanr\u0131s\u0131\u2019d\u0131r.<\/p>\n

Volkanlar, s\u0131cak magmay\u0131 d\u0131\u015far\u0131ya att\u0131klar\u0131 gibi, su buhar\u0131 ve di\u011fer gazlar\u0131, \u00f6rne\u011fin k\u00fck\u00fcrt oksitleri (SO2, SO), karbondioksit (CO2) ve karbonmonoksitleri de (CO) d\u0131\u015far\u0131ya \u00e7\u0131kart\u0131rlar. Ayr\u0131ca, k\u0131zg\u0131n k\u00fcller ve \u00e7ok \u00e7e\u015fitli kat\u0131 malzeme de f\u0131rlat\u0131rlar. \u00d6rne\u011fin volkan bombas\u0131, lapilli ad\u0131 verilen f\u0131nd\u0131k b\u00fcy\u00fckl\u00fc\u011f\u00fcndeki volkanik malzemelerin b\u00fcy\u00fck bir bas\u0131n\u00e7la d\u0131\u015far\u0131ya f\u0131rlat\u0131lmas\u0131yla olu\u015fur. Y\u00fcksek s\u00fcrat nedeniyle, volkan bombalar\u0131n\u0131n her iki ucu sarmal bi\u00e7imli olur.<\/p>\n

Volkanlar\u0131n olu\u015fumu<\/strong><\/p>\n

Volkanlar genelde uzakla\u015fan ve yak\u0131nla\u015fan tektonik levhalar\u0131n bulundu\u011fu yerlerde geli\u015fir. \u00d6rne\u011fin Orta Atlantik Okyanus s\u0131rt\u0131, levhalar\u0131n birbirinden uzakla\u015fmas\u0131 sonras\u0131nda, bazaltik magman\u0131n deniz alt\u0131 volkanizmas\u0131 \u015feklinde okyanus taban\u0131ndan yukar\u0131 \u00e7\u0131kmas\u0131yla olu\u015fmu\u015ftur. Di\u011fer bir \u00f6rnek de Pasifik Ate\u015f Halkas\u0131\u2019nda g\u00f6r\u00fcl\u00fcr ki bu da tektonik levhalar\u0131n birbirlerine yakla\u015fmas\u0131 sonucunda g\u00f6r\u00fclen deniz alt\u0131 volkanizmas\u0131d\u0131r. Volkanlar ayr\u0131ca ve genellikle, yerkabu\u011funun zay\u0131f zonlar\u0131n\u0131 tercih ederek magman\u0131n yery\u00fcz\u00fcne \u00e7\u0131kt\u0131\u011f\u0131 yerlerde olu\u015fur. \u00d6rne\u011fin Afrika Rift Vadisi, Rio Grande Rifti gibi. S\u0131cak magman\u0131n yery\u00fcz\u00fcne \u00e7\u0131kt\u0131\u011f\u0131 noktalara s\u0131cak nokta ya da hot-spot ad\u0131 verilir. Bunlar \u00f6zellikle Pasifik Okyanusu\u2019nda \u00e7ok yayg\u0131nd\u0131r. Birka\u00e7 \u00f6rnek verirsek Hawai, Galapagos Adalar\u0131 \u00f6nemli s\u0131cak noktalard\u0131r.<\/p>\n

Volkan tipleri<\/strong><\/p>\n

\u00c7atlak tipi volkanlar:<\/strong> Bu tip volkanlar birka\u00e7 metre ila kilometrelerce uzunlukta olan \u00e7atlak ya da yar\u0131klard\u0131r. Buradan \u00e7\u0131kan lav, genelde bazalt ak\u0131nt\u0131lar\u0131 \u015feklindedir. Bu tip volkanlarda kaldera olarak tan\u0131mlayabilece\u011fimiz k\u0131sm\u0131 (volkan\u0131n a\u011fz\u0131, krateri) d\u00fczd\u00fcr. Bunlar karada olabildi\u011fi gibi, okyanus taban\u0131nda da bulunabilir. Bu tip volkanlar genelde yar\u0131klardan lav \u00e7\u0131k\u0131\u015flar\u0131 olarak bilinir ve en tipik \u00f6rnekleri Do\u011fu Afrika Rift Vadileri\u2019nde g\u00f6r\u00fcl\u00fcr.<\/p>\n

\"\"
Volkanlar genelde uzakla\u015fan ve yak\u0131nla\u015fan tektonik levhalar\u0131n bulundu\u011fu yerlerde geli\u015fir.<\/figcaption><\/figure>\n

Kalkan tipi volkanlar:<\/strong> \u015eekilleri nedeniyle bu ismi alm\u0131\u015flard\u0131r. D\u00fc\u015f\u00fck ak\u0131c\u0131l\u0131ktaki lavlardan olu\u015fmu\u015ftur. Lavlar ana \u00e7\u0131k\u0131\u015f yerinden \u00e7ok uzun mesafelere kadar akabilme \u00f6zelli\u011fine sahiptir. Katastrofik patlamalar bu tip volkanlarda g\u00f6zlenmez. D\u00fc\u015f\u00fck akmazl\u0131ktaki (viskozitedeki) magma, d\u00fc\u015f\u00fck silis oran\u0131na sahiptir. Kalkan tipli volkanlar k\u0131tasal yerle\u015fimlerde, okyanus yerle\u015fmelerinden daha azd\u0131r. Hawai volkan zinciri, tipik kalkan tipli volkanlardan meydana gelmi\u015ftir ve ayr\u0131ca \u0130zlanda volkanlar\u0131 da bu tip olmalar\u0131yla dikkati \u00e7eker.<\/p>\n

Lav kubbeleri \u015feklindeki volkanlar:<\/strong> Bu tip volkanlar genelde kaba, dairesel, tepe bi\u00e7imli \u00e7\u0131k\u0131nt\u0131lar \u015feklindedir. Son derece yava\u015f akan lav, y\u00fcksek silikat bile\u015fimli bazalt ya da riyolittir. St. Helen Yanarda\u011f\u0131 bu tiptedir.<\/p>\n

Cryptodom (gizli kubbe) \u015feklindeki volkanlar:<\/strong> Cryptodom ya da gizli kubbeler ak\u0131c\u0131 olamayan lav i\u00e7erir ve bu nedenle bir balon gibi lav \u00e7\u0131k\u0131nt\u0131s\u0131 olu\u015fur. \u00d6rne\u011fin 1980\u2019deki St. Helen volkanik patlamas\u0131nda, y\u00fcksek bas\u0131n\u00e7 alt\u0131ndaki lav \u00e7\u0131k\u0131nt\u0131s\u0131 aniden patlayarak da\u011f\u0131n kuzey k\u0131sm\u0131n\u0131n bir anda yok olmas\u0131na neden olmu\u015ftur. Bu katastrofik patlamaya \u00f6nemli bir \u00f6rnek olarak bilimsel kay\u0131tlara ge\u00e7mi\u015ftir.<\/p>\n

Volkanik ya da k\u00fcl konileri:<\/strong> Bu tip volkanlarda p\u00fcsk\u00fcrme, taneli piroklastik malzeme \u015feklindedir. Bu nedenle bunlara volkanik koni ya da k\u00fcl konileri ad\u0131 verilir. Piroklastik malzeme t\u00fcm bacan\u0131n etraf\u0131n\u0131 sarm\u0131\u015f bi\u00e7imdedir. Bu malzemenin y\u00fcksekli\u011fi yakla\u015f\u0131k 30-400 m kadar olabilir. New Meksika ve Arizona\u2019da bu tip k\u00fcl konileri olduk\u00e7a yayg\u0131nd\u0131r.<\/p>\n

Strato volkanlar:<\/strong> Bu volkan tipi kar\u0131\u015f\u0131k yap\u0131l\u0131d\u0131r. Volkan\u0131n yap\u0131s\u0131ndaki karma\u015f\u0131kl\u0131k ve konik yap\u0131, lav ak\u0131nt\u0131lar\u0131 ile volkan\u0131n \u00e7\u0131kartt\u0131\u011f\u0131 di\u011fer piroklastik malzemelerin ard\u0131\u015f\u0131kl\u0131 olarak s\u0131ralanmas\u0131ndan olu\u015fmu\u015ftur. En g\u00fczel \u00f6rne\u011fi Vez\u00fcv\u2019d\u00fcr. Stromboli de \u00f6nemli strata tip volkand\u0131r. Bunlar\u0131n patlamalar\u0131 tarihte \u00f6nemli katastrofik olaylara neden olmu\u015f, binlerce insan hayat\u0131n\u0131 kaybetmi\u015ftir. \u00d6rne\u011fin Vez\u00fcv\u2019\u00fcn 24 A\u011fustos 79\u2019da patlamas\u0131 sonras\u0131 p\u00fcsk\u00fcrtt\u00fc\u011f\u00fc piroklastik malzeme (k\u0131zg\u0131n k\u00fcl, \u00e7amur ve lav kar\u0131\u015f\u0131m\u0131) da\u011f\u0131n ete\u011findeki Pompei \u015eehri\u2019ni haritadan silmi\u015f ve binlerce ki\u015fi hayat\u0131n\u0131 kaybetmi\u015ftir. G\u00fcn\u00fcm\u00fczde bu katastrofik felaketi g\u00f6steren t\u00fcm ayr\u0131nt\u0131lar, bir a\u00e7\u0131k hava m\u00fczesinde koruma alt\u0131na al\u0131nm\u0131\u015ft\u0131r.<\/p>\n

S\u00fcper volkanlar:<\/strong> Bu volkanlar\u0131n, b\u00fcy\u00fck kalderalar\u0131 ile her zaman i\u00e7in k\u0131tasal \u00f6l\u00e7ekte tahribat potansiyeli vard\u0131r. Bunlar\u0131n jeoloji tarihi boyunca olu\u015fturduklar\u0131 patlamalar yoluyla atmosfere sald\u0131klar\u0131 y\u00fcksek orandaki k\u00fck\u00fcrt ve k\u00fcl, volkanik k\u0131\u015flar\u0131n olu\u015fumuna neden olmu\u015f, k\u00fcresel \u00f6l\u00e7ekte \u0131s\u0131 d\u00fc\u015fm\u00fc\u015f, b\u00fcy\u00fck felaketler meydana gelmi\u015ftir. Dinozorlar\u0131n yok olu\u015funda s\u00fcper volkanlar\u0131n rol\u00fc oldu\u011fu d\u00fc\u015f\u00fcn\u00fclmektedir. G\u00fcn\u00fcm\u00fczde s\u00fcper volkan \u00f6zelli\u011fine sahip en \u00f6nemli \u00f6rneklerin ba\u015f\u0131nda Amerika\u2019daki Yellowstone Kalderas\u0131 gelir. Yeni Zelanda\u2019da ki Taupo G\u00f6l\u00fc, Sumatra\u2019daki Toba G\u00f6l\u00fc ile Tanzanya\u2019da ki Ngorogora Krateri de s\u00fcper volkand\u0131r.<\/p>\n

Denizalt\u0131 volkanlar\u0131:<\/strong> Yayg\u0131n olarak deniz taban\u0131nda bulunur ve olu\u015furlar. Baz\u0131lar\u0131 s\u0131\u011f sularda aktif olabilir. Onlar\u0131n meydana geli\u015fleri deniz y\u00fczeyinden e\u011fim a\u015fa\u011f\u0131 yuvarlanan b\u00fcy\u00fck lav bloklar\u0131n\u0131n gaz patlamalar\u0131 \u015feklindedir. Bunlar\u0131n \u00fcr\u00fcnleri \u00e7ok klasik olarak bazaltik k\u00f6kenli yast\u0131k lavlar\u0131d\u0131r. Hidrotermal damarlar bu volkanlar\u0131n yan\u0131nda bulunur ve ilgin\u00e7 g\u00f6r\u00fcn\u00fcml\u00fc canl\u0131lar\u0131n ya\u015fad\u0131\u011f\u0131 denizalt\u0131 ekosistemlerinin geli\u015fimini desteklerler.<\/p>\n

Subglasiyal volkanlar:<\/strong> Tabla tipi volkanlar da denilir. Bu volkanlar buz \u015fapkalar\u0131n\u0131n alt\u0131nda geli\u015fir. D\u00fczg\u00fcn lavlardan olu\u015fmu\u015flard\u0131r. Genelde bile\u015fimleri yast\u0131k lavlar\u0131 ve bazalta benzeyen palagonittir. Buz \u015fapkas\u0131 eridi\u011finde, tepedeki lav \u00e7\u00f6ker. En tipik \u00f6rne\u011fi \u0130zlanda\u2019da bulunan ve yak\u0131nlarda, 22 Mart 2010\u2019da patlayan, Eyyafyallay\u00f6k\u00fcll Buzulu alt\u0131ndaki volkand\u0131r. Ayr\u0131ca \u0130ngiliz Kolombiyas\u0131\u2019ndaki Tuya Volkan\u0131 da bu tiptedir.<\/p>\n

\u00c7amur volkanlar\u0131:<\/strong> Bu volkan jeolojik olarak likit ve gaz \u00e7\u0131kartan \u00e7amur domlar\u0131 (kubbeleri) \u015feklindedir. Boyutlar\u0131 bazen 10 km \u00e7ap\u0131nda olabilmektedir.<\/p>\n

\"\"
Volkan Bombas\u0131.<\/figcaption><\/figure>\n

Volkan \u00fcr\u00fcnleri<\/strong><\/p>\n

Bunlar akan lavlar\u0131n olu\u015fturdu\u011fu ve volkan\u0131n b\u00fcy\u00fck bir bas\u0131n\u00e7la atmosfere f\u0131rlatt\u0131\u011f\u0131 piroklastik denilen malzemelerdir.<\/p>\n

Lav ak\u0131nt\u0131lar\u0131:<\/strong> Bloklar ya da volkan bombalar\u0131, \u00e7ok ak\u0131\u015fkan lav ak\u0131nt\u0131lar\u0131, yast\u0131k lavlar\u0131.<\/p>\n

Piroklastik malzeme:<\/strong> Volkanik k\u00fcller, bloklar, volkanik bombalar.<\/p>\n

Volkanik bombalar bi\u00e7imlerine g\u00f6re isim alabilir. \u00d6rne\u011fin fusiform, \u015ferit, inek teze\u011fi, k\u00fcresel ve d\u00fczensiz bi\u00e7imli volkanik bombalar. Lav kitlesi s\u00fcratle kraterden f\u0131rlad\u0131\u011f\u0131nda, atmosfere y\u00fckselirken ve h\u0131z\u0131n\u0131 kaybedip a\u015fa\u011f\u0131ya d\u00fc\u015ferken, \u00e7ok de\u011fi\u015fik bi\u00e7imlerde \u015fekillenebilmektedir.<\/p>\n

Volkan bombalar\u0131n\u0131n g\u00fczel \u00f6rneklerini, \u00fclkemizde Van-Do\u011fubeyaz\u0131t aras\u0131ndaki Tend\u00fcrek ve S\u00fcphan volkanlar\u0131n\u0131n k\u00fclleri aras\u0131nda g\u00f6rebilirsiniz.<\/p>\n

Kaynak: <\/strong>Mehmet Sak\u0131n\u00e7, 50 Soruda Yer\u2019in Evrimi, Bilim ve Gelecek Kitapl\u0131\u011f\u0131, Ocak 2011, 1.Bask\u0131. s.65-69<\/p>\n","protected":false},"excerpt":{"rendered":"

Volkanlar \u00e7e\u015fitli olmalar\u0131na ra\u011fmen, tan\u0131mlar\u0131 \u00e7ok basittir. Volkan, magma k\u00f6kenli lavlar\u0131n d\u0131\u015far\u0131ya \u00e7\u0131kmas\u0131n\u0131 sa\u011flayan, yerkabu\u011funda olu\u015fmu\u015f bir k\u0131r\u0131k ya da a\u00e7\u0131kl\u0131kt\u0131r. Volkan kelimesinin k\u00f6keni Sicilya dilinde \u201cVurcanu\u201ddur. Vulcano (Roma dilinde) Tirheniyen Denizi\u2019nde k\u00fc\u00e7\u00fck bir volkanik adad\u0131r ve Sicilya\u2019n\u0131n 25 km kuzeyinde bulunur. Di\u011fer taraftan Vulkan, Roma\u2019n\u0131n Ate\u015f Tanr\u0131s\u0131\u2019d\u0131r. Volkanlar, s\u0131cak magmay\u0131 d\u0131\u015far\u0131ya att\u0131klar\u0131 gibi, su […]<\/p>\n","protected":false},"author":429,"featured_media":36399,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[19],"tags":[2750,4079,2895,5239,422],"class_list":["post-36398","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-bilim-gundemi","tag-lav","tag-volkan","tag-volkanizma","tag-yanardag","tag-yerin-evrimi"],"acf":[],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t