The reactions between pyroxenes and carbonates have been studied in the CaMgSi₂O₆ + MgCO₃ (Di + 2Mgs), CaMgSi₂O₆ + NaAlSi₂O₆ + 2MgCO₃ (Di + Jd + 2Mgs), CaMgSi₂O₆ + Na₂Mg(CO₃)₂ (Di + Eit), and CaMgSi₂O₆ + K₂Mg(CO₃)₂ (Di + K₂Mg) systems at pressures of 3.0 and 4.5 GPa in the temperature range 850–1300 °C and compared with those established previously at 6.0 GPa. The Di + 2Mgs solidus locates at 1220 °C / 3 GPa and 1400 °C / 6 GPa. Near-solidus melt is carbonatitic with SiO₂ < 4 wt% and Ca# 56. The Di + Jd + 2Mgs solidus locates near 1050 °C at 3 GPa, rises to 1200 °C at 4.5 GPa, and 1350 °C at 6 GPa. The solidus is controlled by the reaction: 4NaAlSi₂O₆·2CaMgSi₂O₆ (clinopyroxene) + 12MgCO₃ (magnesite) = 2MgAl₂SiO₆·5Mg₂Si₂O₆ (clinopyroxene) + 2[Na₂CO₃·CaCO₃·MgCO₃] (liquid) + 6CO₂. As pressure increases, the composition of solidus melt evolves from 26Na₂CO₃∙74Ca_0.58Mg_0.42CO₃ at 3 GPa to 10Na₂CO₃∙90Ca_0.50Mg_0.50CO₃ at 6 GPa. Melting in the Di + Eit and Di + K₂Mg systems is controlled by the reactions: CaMgSi₂O₆ (clinopyroxene) + 2(Na or K)₂ Mg(CO₃)₂ (eitelite) = Mg₂Si₂O₆ (orthopyroxene) + 2[(Na or K)₂CO₃∙Ca_0.5Mg_0.5CO₃] (liquid). The Di + Eit solidus locates at 925 °C / 3 GPa and 1100 °C / 6 GPa, whereas the Di + K₂Mg solidus is located at 50 °C lower. The resulting melts have alkali-rich carbonate compositions, (Na or K)₂CO₃∙Ca_0.4Mg_0.6CO₃. The obtained results suggest that most carbonates belong to the ultramafic suite would survive during subduction into the deep mantle and experience partial melting involving alkaline carbonates, eitelite or K₂Mg(CO₃)₂, under geothermal conditions of the subcontinental lithospheric mantle (35–40 mW/m²). On the other hand, the jadeite component in clinopyroxene would be an important fluxing agent responsible for the partial melting of carbonated rocks under the rift margin geotherm (60 mW/m²) at a depth of about 100 km, yielding the formation of Na-carbonatite melt.

在CaMgSi ₂ O ₆  + MgCO ₃（Di + 2Mgs），CaMgSi ₂ O ₆  + NaAlSi ₂ O ₆  + 2MgCO ₃（Di + Jd + 2Mgs），CaMgSi ₂ O ₆  + Na中研究了辉石与碳酸盐之间的反应₂ Mg（CO ₃）₂（Di + Eit）和CaMgSi ₂ O ₆  + K ₂ Mg（CO ₃）₂（Di + K ₂Mg）系统在850-1300°C的温度范围内处于3.0和4.5 GPa的压力下，与之前建立的6.0 GPa的系统进行了比较。Di + 2Mgs固相线的温度为1220°C / 3 GPa和1400°C / 6 GPa。接近固相线的熔体是含SiO ₂  <4 wt％和Ca＃56的碳酸盐岩。Di + Jd + 2Mgs固相线在3 GPa时位于1050°C附近，在4.5 GPa时升至1200°C，在6 GPa时升至1350°C 。固相线受以下反应控制：4NaAlSi ₂ O ₆ ·2CaMgSi ₂ O ₆（斜向吡咯）+ 12MgCO ₃（菱镁矿）= 2MgAl ₂ SiO ₆ ·5Mg ₂ Si ₂ O ₆（斜向吡咯）+ 2 [Na ₂ CO₃ ·CaCO ₃ ·MgCO ₃ ]（液体）+ 6CO ₂。随着压力的增加，固相线熔体的组成从3 GPa时的26Na ₂ CO ₃ ∙74Ca _0.58 Mg _0.42 CO ₃演变为6 GPa时的10Na ₂ CO ₃ ∙90Ca _0.50 Mg _0.50 CO ₃。Di + Eit和Di + K ₂ Mg系统中的熔融受以下反应控制：CaMgSi ₂ O ₆（斜向芴）+ 2（Na或K）₂  Mg（CO ₃）₂（沸石）= Mg ₂Si ₂ O ₆（邻二甲苯）+ 2 [（（Na或K）₂ CO ₃ ∙Ca _0.5 Mg _0.5 CO ₃ ]]（液体）。Di + Eit固相线位于925°C / 3 GPa和1100°C / 6 GPa，而Di + K ₂ Mg固相线位于低50°C。所得的熔体具有富含碱的碳酸盐成分，（Na或K）₂ CO ₃ ∙Ca _0.4 Mg _0.6 CO ₃。获得的结果表明，大多数属于超镁铁质碳酸盐的碳酸盐都将在俯冲到深地幔的过程中幸存下来，并经历部分熔化，包括碱性碳酸盐，iteitelite或K _2。Mg（CO ₃）₂，在亚大陆岩石圈地幔的地热条件下（35–40 mW / m ²）。另一方面，斜辉石中的翡翠成分是重要的助熔剂，负责裂谷缘地热（60 mW / m ²）下约100 km深度的碳酸盐岩的部分熔融，形成了Na-碳酸盐熔体。