| Инд. авторы: | Fedoraeva A.S., Shatskiy A., Litasov K.D. |
| Заглавие: | The join CaCO3-CaSiO3 at 6 GPa with implication to Ca-rich lithologies trapped by kimberlitic diamonds. |
| Библ. ссылка: | Fedoraeva A.S., Shatskiy A., Litasov K.D. The join CaCO3-CaSiO3 at 6 GPa with implication to Ca-rich lithologies trapped by kimberlitic diamonds. // High Pressure Research. - 2019. - Т.4. - № 39. |
| Внешние системы: | DOI: 10.1080/08957959.2019.1660325; WoS: 000485108100001; SCOPUS: 2-s2.0-85071975530; |
| Реферат: | eng: Phase relations in the CaCO3-CaSiO3 system have been studied at 6 GPa and 1300-1750 degrees C. At 1300 degrees C, the subsolidus assemblage comprises of aragonite and walstromite. The eutectic was established at 1400 degrees C and 57 mol% CaSiO3. Just below its melting temperature at 1660 degrees C, the CaCO3 solid quenches to calcite, while, at <= 1600 degrees C, it quenches to aragonite. At 1700 degrees C, a walstromite + larnite + liquid assemblage appears, indicating that the system deviates from a simple binary. Incongruent melting of walstromite to produce larnite and a liquid occurs at 1750 degrees C. The diamonds containing inclusions of walstromite and CaCO3 could be formed as a result of the partial reduction of the CaCO3-CaSiO3 melt derived by melting of walstromite-bearing CaCO3 limestones on the top of basaltic crust subducted to a depth of >= 180 km and warming to >= 1400 degrees C.
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| Ключевые слова: | aragonite; walstromite; superdeep diamonds; PHASE-RELATIONS; HIGH-PRESSURE; KANKAN DIAMONDS; CaCO3-CaSiO3; KILOBARS; MELTS; EQUILIBRIUM; TRANSITIONS; INCLUSIONS; SUBSOLIDUS; SYSTEM; Ca-rich lithology in the mantle; |
| Издано: | 2019 |