Puas yog cov viscosities ntawm magmas nce nrog nce feem pua ntawm silica?
Puas yog cov viscosities ntawm magmas nce nrog nce feem pua ntawm silica?

Video: Puas yog cov viscosities ntawm magmas nce nrog nce feem pua ntawm silica?

Video: Puas yog cov viscosities ntawm magmas nce nrog nce feem pua ntawm silica?
Video: Lub paum tsi muaj kua li es yuav ua cas thiaj muaj kua 5/3/2021 2024, Hlis ntuj nqeg
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Cov viscosities ntawm magmas nce nrog nce feem pua ntawm silica . Kev tawg ntawm cov roob hluav taws Hawaii tuaj yeem piav qhia tias tawg tau sib piv rau xyoo 1980 Mount St. Helens eruption. Basaltic lavas feem ntau yog kub dua thiab khov dua li andesite lavas.

Ib yam li ntawd ib tug yuav nug, uas magma muaj pes tsawg leeg yog feem ntau tawg?

Gas muab magmas lawv tawg tus cwj pwm, vim tias qhov ntim ntawm cov pa nthuav tawm thaum lub siab txo. Cov muaj pes tsawg leeg ntawm cov gases hauv magma yog: Feem ntau H2O (dej vapor) & qee qhov CO2 (cov pa roj carbon dioxide)

Kub ntawm Magmas

  • Basaltic magma - 1000 txog 1200oC.
  • Andesitic magma - 800 rau 1000oC.
  • Rhyolitic magma - 650 txog 800oC.

Qhov thib ob, qhov muaj pes tsawg leeg ntawm magma cuam tshuam li cas? Magmas txawv hauv muaj pes tsawg leeg , qho cuam tshuam viscosity. Magma muaj pes tsawg leeg muaj loj nyhuv pe qas a roob hluav taws tawg. Felsic lavas yog viscous ntau dua thiab tawg explosively los yog ua tsis yog tawg . Mafic lavas tsis tshua khov thiab tawg effusively.

Hais txog qhov no, cov ntsiab lus silica cuam tshuam li cas rau viscosity ntawm magma?

Magmas uas muaj siab silica cov ntsiab lus Yog li ntawd yuav ua kom pom ntau dua ntawm polymerization, thiab muaj viscosities siab dua, dua li cov uas muaj tsawg- silica cov ntsiab lus . Tus nqi ntawm yaj gases nyob rau hauv lub magma kuj cuam tshuam nws yog viscosity , tab sis nyob rau hauv ib txoj kev tsis meej tshaj qhov kub thiab txias silica cov ntsiab lus.

Yam twg ntawm cov magma hauv qab no muaj cov ntsiab lus roj ntau tshaj?

Felsic magma muaj cov ntsiab lus silica siab tshaj plaws ntawm tag nrho magma hom , ntawm 65-70%. Yog li ntawd, felsic magma kuj muaj cov roj ntau tshaj plaws thiab viscosity, thiab qis tshaj qhov ntsuas kub, ntawm 650 ° thiab 800 ° C (1202 ° thiab 1472 ° Fahrenheit).

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