Dunite tshwm sim hauv layered, gabbroic igneous complexes (saib gabbro). Tej zaum nws yuav tshwm sim los ntawm cov tsub zuj zuj ntawm ntom, thaum ntxov crystallizing nplej ntawm olivine uas tog rau hauv qab ntawm tsawg silica magma. Intrusion ntawm dunite daim ntawv sills los yog dikes.
Dunite txheej twg los?
Dunite yog cov neeg nplua nuj olivine kawg ntawm peridotite pawg ntawm mantle-derived pob zeb. Dunite thiab lwm cov pob zeb peridotite yog suav tias yog cov khoom tseem ceeb ntawm lub ntiaj teb lub mantle saum qhov tob ntawm 400 km (250 mi).
Dunite tsim yooj yim li cas?
Cumulative dunite yog tsim los ntawm feem ntawm olivine los ntawm mafic yajHloov dunite yog cov khoom lag luam ntawm cov tshuaj tiv thaiv ntawm pyroxene-cov kabmob host pob zeb thiab olivine-saturated magma, uas dissolves orthopyroxene hauv tus tswv tsev peridotite thiab qee zaum crystallizes olivine.
Dab tsi yog pob zeb tsis pom kev yog dunite?
Dunite yog ib qho igneous plutonic pob zeb ntawm ultramafic muaj pes tsawg leegnrog ntxhib-grained granular lossis phaneritic kev ntxhib los mos thiab feem ntau loj lossis txheej.
Dunite yog dab tsi?
Dunite yog pob zeb ultramafic plutonic uas yog tsim los ntawm olivine "Ultramafic" txhais tau tias mafic minerals tsim ntau dua 90% ntawm cov pob zeb muaj pes tsawg leeg. Feem ntau cov mafic minerals nyob rau hauv ultramafic pob zeb yog tiag tiag pyroxenes thiab olivine (yog hais tias hornblende yog tam sim no nws yog ntxiv rau pyroxenes).
