Volcanic Rock yog dab tsi?
Jan 17, 2024| Cov pob zeb hluav taws xob xa mus rau cov pob zeb tsim los ntawm kev sib xyaw ntawm cov magma kub ntawm qhov tob hauv ntiaj teb los ntawm cov volcanic vents, uas tuaj yeem muab faib ua cov pob zeb nqaim volcanic thiab cov pob zeb volcanic dav.
Narrowly txhais, volcanic pob zeb hais txog volcanic lava, uas yog ib hom uas tsis muaj viscosity, tsis tshua muaj volatile magma (xws li yooj yim magma) uas ntws tawm ntawm lub roob hluav taws nyob rau hauv daim ntawv ntawm yaj. Nyob rau hauv lub lig theem ntawm ib tug volcanic eruption, ib co high viscosity acidic magma kuj tuaj yeem tsim lava thaum muaj ntau cov teeb meem tsis haum xeeb hauv magma chamber khiav tawm thiab nkag mus rau saum npoo.
Cov muaj pes tsawg leeg ntawm magma yog txawv, thiab cov pob zeb tsim tom qab txias thiab solidification kuj txawv. Cov pob zeb extrusive yog basalt, cov pob zeb nruab nrab extrusive yog andesite, cov pob zeb acidic extrusive yog rhyolite, thiab semi alkaline thiab alkaline extrusive pob zeb yog trachyte thiab phonolite.
Cov pob zeb ejected feem ntau muaj cov qauv xws li pores, almonds, thiab cov qauv ntws, thiab feem ntau yog tsim los ntawm cov iav, cryptocrystalline, lossis porphyritic cov qauv. Glassy obsidian, perlite, turquoise, pumice, thiab lwm yam pob zeb tawg yog hu ua volcanic glassy pob zeb.
Hauv kev txiav txim siab dav, pob zeb volcanic suav nrog tsis yog lava xwb tab sis kuj yog pob zeb pyroclastic. Cov pob zeb pob zeb volcanic feem ntau yog cov pob zeb acidic nrog cov viscosity siab thiab cov ntsiab lus tsis zoo uas yuav tawg mus rau saum npoo los ntawm kev tawg tawg, feem ntau sib xyaw nrog qee cov sediment lossis cov khoom lava.