Glacier hav

glacier hauv iceland

Glacier valleys, tseem hu ua ice valleys, xa mus rau kwj ha uas loj-scale glaciers circulate los yog ib zaug circulated, tawm ntshiab glacial landforms. A glacier hav Nws yog ib qho tseem ceeb heev rau biodiversity ntawm ecosystems thiab ecological tshuav nyiaj li cas.

Vim li no, peb yuav qhia koj txhua yam koj yuav tsum paub txog dab tsi lub hav glacial yog, nws cov yam ntxwv geomorphology.

Dab tsi yog lub hav glacial

cantabrian hav

Cov hav dej glacial, uas feem ntau hu ua glacial troughs, yog cov kwj ha uas peb tuaj yeem pom tau tias lawv tau tso tseg cov ntawv nyem ntawm cov dej khov.

Nyob rau hauv luv luv, glacial hav zoo li glaciers. Glacial kwj ha yog tsim thaum cov dej khov loj sib sau ua ke hauv glacial cirques. Cov dej khov los ntawm cov khaubncaws sab nraud nws thiaj li txav mus rau hauv qab ntawm lub hav, qhov twg nws thiaj li dhau los ua lub pas dej.

Ib qho ntawm cov yam ntxwv tseem ceeb ntawm cov hav dej glacial yog tias lawv muaj qhov zoo li tus ntoo khaub lig, uas yog vim li cas lawv tseem hu ua glacial troughs. Qhov no feature yog lub ntsiab feature uas tso cai rau geologists paub qhov txawv ntawm cov kwj ha uas loj npaum li cas ntawm cov dej khov swb los yog puas tau swb. Lwm cov cim ntawm glacial kwj ha yog lawv hnav thiab dhau-kev khawb cov cim, tshwm sim los ntawm kev sib txhuam ntawm cov dej khov thiab cov khoom rub tawm.

Ancient glaciers nyob rau hauv lub ntiaj teb tso cov khoom yav tas los eroded los ntawm dej khov. Cov ntaub ntawv no yog heterogeneous heev, thiab feem ntau sib txawv hom moraines, xws li hauv qab moraines, sab moraines, tumbling moraines, thiab txawm phem dua, nruab nrab ntawm lub pas dej nto moo glacial feem ntau yog tsim. Piv txwv ntawm tom kawg yog cov pas dej glacial uas peb tuaj yeem pom ntawm cov npoo ntawm European Alps (hu ua Como, Tus Tswv Cuab, Garda, Geneva, Constanta, thiab lwm yam) lossis hauv qee thaj chaw hauv nruab nrab Sweden thiab ntau lwm tus.

Dynamics ntawm lub hav glacial

glacial hav nta

Hais txog cov txheej txheem yaig ntawm cov dej khov, nws yog ib qho tseem ceeb uas yuav tsum tau taw qhia tias cov glaciers yog cov erosive heev thiab tuaj yeem ua raws li txoj siv sia rau cov khoom siv ntawm txhua qhov ntau thiab tsawg pab txhawb nqa los ntawm txoj kab nqes, thauj lawv mus rau hauv hav.

Ntxiv thiab, muaj ntau npaum li cas ntawm meltwater nyob rau hauv lub glacier, uas tuaj yeem ncig ntawm kev kub ceev hauv qhov tunnels hauv glacier, thauj cov khoom nyob rau hauv qab ntawm lub glacier, thiab cov subglacial tam sim no zoo heev. Cov khoom uas nws nqa ua kom puas, thiab pob zeb nyob rau hauv lub glacier yuav crushed mus rau hauv ib tug zoo sib tov ntawm silt thiab glacier av nplaum hmoov.

Glaciers tuaj yeem ua haujlwm hauv peb txoj hauv kev tseem ceeb thiab lawv yog: glacial pib, abrasion, thrust.

Nyob rau hauv qhov tawg thaiv quarrying, lub zog ntawm cov dej khov tuaj yeem txav thiab nqa cov chunks loj ntawm cov pob zeb tawg. Qhov tseeb, qhov ntev ntawm lub txaj glacier yog qhov tsis sib xws, nrog cov cheeb tsam uas nthuav dav thiab sib sib zog nqus hauv daim ntawv ntawm kev nyuaj siab hu ua troughs lossis troughs, uas tob zuj zus los ntawm kev khawb ntawm cov pob zeb tsawg dua thiab muaj zog dua. Tom qab ntawd, thaj chaw yog nqaim thiab hu ua latch lossis qhov pib.

Hauv ntu ntu, cov platforms tau tsim nyob rau hauv cov pob zeb muaj zog uas flatten tawm ntawm qhov siab, hu ua lub xub pwg pads. Abrasion muaj xws li kev sib tsoo, scraping, thiab sib tsoo ntawm bedrock los ntawm rougher ice-borne pob zeb tawg. Qhov no tsim cov khawb thiab grooves. Hauv polishing, nws yog cov ntsiab lus zoo, zoo li cov ntawv xuab zeb ntawm pob zeb.

Nyob rau tib lub sijhawm, vim kev puas tsuaj, pob zeb yog crushed, ua av nplaum thiab silt, hu ua ice hmoov vim hais tias ntawm nws zoo grain loj, uas muaj nyob rau hauv cov dej yaj thiab muaj cov tsos ntawm skimmed mis nyuj.

Los ntawm thrust, lub glacier thauj thiab thawb mus rau nws tus kheej cov khoom decomposing uas nws crushes thiab transforms raws li tau piav saum toj no.

daim ntawv ntawm erosion

glacier hav

Ntawm lawv tau lees paub circuses, tarn, ridges, horn, caj dab. Thaum ua qauv glacial kwj ha, lawv nyiam nyob hauv cov hav uas twb muaj lawm, uas nthuav dav thiab tob rau hauv U-puab. Glaciers kho thiab ua kom yooj yim cov nkhaus ntawm cov kwj hav qub thiab cov pob zeb eroded, tsim cov duab peb sab loj lossis truncated spurs.

Nyob rau hauv ib txwm longitudinal profile ntawm ib tug glacial hav, kuj tiaj basins thiab extensions ua raws li ib tug, tsim chains ntawm pas dej uas tau txais lub npe ntawm peb niam txiv thaum lub basins sau nrog dej.

Rau lawv, Hanging Valley yog ib qho chaw qub qub ntawm lub qhov dej khov loj. Lawv tau piav qhia vim hais tias kev yaig ntawm cov dej khov yog nyob ntawm qhov tuab ntawm daim ntawv dej khov, thiab cov dej khov tuaj yeem nkag mus tob rau lawv cov kwj deg tab sis tsis yog lawv cov ceg.

Fjords tsim thaum dej hiav txwv nkag mus rau hauv cov hav dej khov, xws li cov hauv Chile, Norway, Greenland, Labrador, thiab sab qab teb fjords hauv Alaska. Lawv feem ntau cuam tshuam nrog kev ua txhaum thiab qhov sib txawv lithological. Lawv ncav cuag qhov tob tob, xws li Messier channel hauv Chile, uas Nws yog 1228 meters tob. Qhov no tuaj yeem piav qhia los ntawm kev khawb ntau dhau ntawm cov dej khov eroding hauv qab hiav txwv.

Glaciation kuj tuaj yeem ua raws li cov pob zeb uas tsim cov pob zeb zoo li yaj, uas nws qhov chaw du, sib npaug zoo li ib pab yaj uas pom los ntawm qhov siab. Lawv nyob rau hauv qhov loj ntawm ib meter mus rau kaum ntawm meters thiab ua raws li cov kev taw qhia ntawm dej khov. Sab ntawm lub qhov dej khov nab kuab muaj qhov profile du vim muaj kev sib tsoo, thaum lwm sab muaj angular thiab irregular profiles vim yog pob zeb tshem tawm.

Cov ntawv ntawm tsub zuj zuj

Cov nplooj ntawv dej khov tau rov qab los txij li lub hnub nyoog dej khov kawg, txog 18.000 xyoo dhau los, qhia txog kev pab cuam qub txeeg qub teg nyob rau txhua ntu lawv nyob hauv lub sijhawm dej khov kawg.

Glacial deposits yog deposits ua los ntawm cov khoom tso ncaj qha los ntawm glaciers, tsis muaj ib tug stratified qauv thiab nws fragments muaj striations. Los ntawm qhov pom ntawm qhov loj ntawm cov nplej, lawv muaj ntau yam sib txawv, xws li cov hmoov nplej glacial mus rau cov khoom tsis ruaj khov thauj 500 km ntawm lawv thaj tsam ntawm keeb kwm, xws li cov uas pom hauv Central Park hauv New York; hauv Chile, hauv San Alfonso, hauv Maipo tub rau khoom. Thaum cov deposits sib xyaw ua ke, lawv tsim tilites.

Lo lus moraine yog siv rau ntau hom ntawv uas feem ntau yog roob. Muaj ntau hom moraines thiab ntev toj hu ua drumlins. Lub frontal moraine yog lub mound nyob rau hauv pem hauv ntej ntawm ib tug glacier uas tsim nyob rau hauv ib tug arc thaum lub glacier tseem nyob ruaj khov nyob rau hauv ib txoj hauj lwm rau xyoo los yog kaum xyoo. Yog hais tias ntws ntawm lub glacier txuas ntxiv, sediment yuav txuas ntxiv mus ntxiv rau ntawm qhov thaiv no. Yog hais tias cov glaciers rov qab, ib txheej ntawm maj mam undulating moraine, hu ua basal moraine, yog tso, xws li nyob rau hauv cov av ntub dej ntawm Great Lakes cheeb tsam ntawm lub tebchaws United States. Ntawm qhov tod tes, yog tias lub glacier tseem thim rov qab, nws cov thawj coj tuaj yeem ruaj khov dua, ua kom rov qab moraine.

Lateral moraines yog ib yam ntawm cov hav dej glaciers thiab nqa sediment raws cov ntug hav, tso cov ridges ntev. Lub hauv paus moraine tsim qhov twg ob sab moraines sib ntsib, xws li ntawm qhov sib txuam ntawm ob lub hav.

Drumlins yog du, slender parallel toj roob hauv pes tsim los ntawm moraine deposits nteg los ntawm continental glaciers. Lawv tuaj yeem ncav cuag li 50 meters thiab ntev ib mais, tab sis feem ntau yog me me. Hauv Ontario, Canada, lawv pom nyob rau hauv cov teb nrog ntau pua tus drumlins. Thaum kawg, cov ntaub ntawv uas muaj stratified glacial fragments xws li kame, kame terraces thiab eskers raug txheeb xyuas.

Kuv vam tias nrog cov ntaub ntawv no koj tuaj yeem kawm paub ntxiv txog dab tsi lub hav glacial yog thiab nws cov yam ntxwv.


Cov ntsiab lus ntawm tsab xov xwm ua raws li peb cov ntsiab cai ntawm kev tswj hwm kev ncaj nceesCov. Tshaj tawm ib qho yuam kev nyem no.

Yog thawj tus tuaj tawm tswv yim

Tso koj saib

Koj email chaw nyob yuav tsis tsum luam tawm.

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  1. Lub luag haujlwm rau cov ntaub ntawv: Miguel Ángel Gatón
  2. Lub hom phiaj ntawm cov ntaub ntawv: Tswj SPAM, kev tswj xyuas tawm tswv yim.
  3. Sau raws cai: Koj kev tso cai
  4. Kev sib txuas lus ntawm cov ntaub ntawv: Cov ntaub ntawv yuav tsis raug xa mus rau lwm tus neeg thib peb tsuas yog los ntawm kev txiav txim siab raug cai.
  5. Cov ntaub ntawv khaws cia: Cov Ntaub Ntawv khaws tseg los ntawm Occentus Networks (EU)
  6. Txoj Cai: Txhua lub sijhawm koj tuaj yeem txwv, rov qab thiab tshem tawm koj cov ntaub ntawv.