link phase transition
Okumaya devam et...
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The upper mantle is dominantly [[peridotite]], composed primarily of variable proportions of the minerals [[olivine]], [[Pyroxene|clinopyroxene]], [[orthopyroxene]], and an aluminous phase. The aluminous phase is [[plagioclase]] in the uppermost mantle, then [[spinel]], and then [[garnet]] below ~{{cvt|100|km}}.<ref>{{cite journal |last1=McDonough |first1=William F. |last2=Rudnick |first2=Roberta L. |editor1-first=Russell J |editor1-last=Hemley |title=Chapter 4. Mineralogy and composition of the upper mantle |journal=Ultrahigh Pressure Mineralogy |date=1998-12-31 |pages=139–164 |doi=10.1515/9781501509179-006|isbn=9781501509179 }}</ref> Gradually through the upper mantle, pyroxenes become less stable and transform into [[Majorite|majoritic garnet]].<ref>{{cite journal |last1=van Mierlo |first1=W. L. |last2=Langenhorst |first2=F. |last3=Frost |first3=D. J.|author3-link=Daniel Frost (earth scientist) |last4=Rubie |first4=D. C. |title=Stagnation of subducting slabs in the transition zone due to slow diffusion in majoritic garnet |journal=Nature Geoscience |date=May 2013 |volume=6 |issue=5 |pages=400–403 |doi=10.1038/ngeo1772|bibcode=2013NatGe...6..400V }}</ref> | The upper mantle is dominantly [[peridotite]], composed primarily of variable proportions of the minerals [[olivine]], [[Pyroxene|clinopyroxene]], [[orthopyroxene]], and an aluminous phase. The aluminous phase is [[plagioclase]] in the uppermost mantle, then [[spinel]], and then [[garnet]] below ~{{cvt|100|km}}.<ref>{{cite journal |last1=McDonough |first1=William F. |last2=Rudnick |first2=Roberta L. |editor1-first=Russell J |editor1-last=Hemley |title=Chapter 4. Mineralogy and composition of the upper mantle |journal=Ultrahigh Pressure Mineralogy |date=1998-12-31 |pages=139–164 |doi=10.1515/9781501509179-006|isbn=9781501509179 }}</ref> Gradually through the upper mantle, pyroxenes become less stable and transform into [[Majorite|majoritic garnet]].<ref>{{cite journal |last1=van Mierlo |first1=W. L. |last2=Langenhorst |first2=F. |last3=Frost |first3=D. J.|author3-link=Daniel Frost (earth scientist) |last4=Rubie |first4=D. C. |title=Stagnation of subducting slabs in the transition zone due to slow diffusion in majoritic garnet |journal=Nature Geoscience |date=May 2013 |volume=6 |issue=5 |pages=400–403 |doi=10.1038/ngeo1772|bibcode=2013NatGe...6..400V }}</ref> |
At the top of the transition zone, olivine undergoes isochemical phase transitions to [[wadsleyite]] and [[ringwoodite]]. Unlike nominally anhydrous olivine, these high-pressure olivine polymorphs have a large capacity to store water in their crystal structure. This has led to the hypothesis that the transition zone may host a large quantity of water.<ref>{{Cite journal|last1=Bercovici|first1=David|last2=Karato|first2=Shun-ichiro|date=September 2003|title=Whole-mantle convection and the transition-zone water filter|journal=Nature|language=En|volume=425|issue=6953|pages=39–44|doi=10.1038/nature01918|pmid=12955133|bibcode=2003Natur.425...39B|s2cid=4428456|issn=0028-0836}}</ref> At the base of the transition zone, ringwoodite decomposes into [[bridgmanite]] (formerly called magnesium silicate perovskite), and ferropericlase. Garnet also becomes unstable at or slightly below the base of the transition zone.<ref>{{cite journal |last1=Anderson |first1=Don L. |last2=Bass |first2=Jay D. |title=Transition region of the Earth's upper mantle |journal=Nature |date=March 1986 |volume=320 |issue=6060 |pages=321–328 |doi=10.1038/320321a0|bibcode=1986Natur.320..321A |s2cid=4236570 }}</ref> | At the top of the transition zone, olivine undergoes isochemical [[phase transition]]s to [[wadsleyite]] and [[ringwoodite]]. Unlike nominally anhydrous olivine, these high-pressure olivine polymorphs have a large capacity to store water in their crystal structure. This has led to the hypothesis that the transition zone may host a large quantity of water.<ref>{{Cite journal|last1=Bercovici|first1=David|last2=Karato|first2=Shun-ichiro|date=September 2003|title=Whole-mantle convection and the transition-zone water filter|journal=Nature|language=En|volume=425|issue=6953|pages=39–44|doi=10.1038/nature01918|pmid=12955133|bibcode=2003Natur.425...39B|s2cid=4428456|issn=0028-0836}}</ref> At the base of the transition zone, ringwoodite decomposes into [[bridgmanite]] (formerly called magnesium silicate perovskite), and ferropericlase. Garnet also becomes unstable at or slightly below the base of the transition zone.<ref>{{cite journal |last1=Anderson |first1=Don L. |last2=Bass |first2=Jay D. |title=Transition region of the Earth's upper mantle |journal=Nature |date=March 1986 |volume=320 |issue=6060 |pages=321–328 |doi=10.1038/320321a0|bibcode=1986Natur.320..321A |s2cid=4236570 }}</ref> |
The lower mantle is composed primarily of bridgmanite and [[ferropericlase]], with minor amounts of [[silicate perovskite|calcium perovskite]], calcium-ferrite structured oxide, and [[stishovite]]. In the lowermost ~{{cvt|200|km}} of the mantle, bridgmanite isochemically transforms into post-perovskite.<ref>{{cite journal |last1=Tsuchiya |first1=Taku |last2=Tsuchiya |first2=Jun |last3=Umemoto |first3=Koichiro |last4=Wentzcovitch |first4=Renata M. |title=Phase transition in MgSiO3 perovskite in the earth's lower mantle |journal=Earth and Planetary Science Letters |date=August 2004 |volume=224 |issue=3–4 |pages=241–248 |doi=10.1016/j.epsl.2004.05.017|bibcode=2004E&PSL.224..241T }}</ref> | The lower mantle is composed primarily of bridgmanite and [[ferropericlase]], with minor amounts of [[silicate perovskite|calcium perovskite]], calcium-ferrite structured oxide, and [[stishovite]]. In the lowermost ~{{cvt|200|km}} of the mantle, bridgmanite isochemically transforms into post-perovskite.<ref>{{cite journal |last1=Tsuchiya |first1=Taku |last2=Tsuchiya |first2=Jun |last3=Umemoto |first3=Koichiro |last4=Wentzcovitch |first4=Renata M. |title=Phase transition in MgSiO3 perovskite in the earth's lower mantle |journal=Earth and Planetary Science Letters |date=August 2004 |volume=224 |issue=3–4 |pages=241–248 |doi=10.1016/j.epsl.2004.05.017|bibcode=2004E&PSL.224..241T }}</ref> |
Okumaya devam et...