The paper reports experimental data on the partial melting of hydrous peridotite and basalt at pressures up to 4 GPa and temperatures up to 1400°С, as well as peridotite–basalt association in the presence of alkaline water–carbonate fluid as an experimental model of mantle reservoir with subducted oceanic protoliths. At partial melting of the hydrous peridotite at 3.7–4.0 GPa and 1000–1300°С, critical relations were observed over the entire studied pressure and temperature interval. At partial melting of hydrous basalt, critical relations between silicate melt and aqueous fluid were recorded at 1000°С and 3.7 GPa. The Na-alkaline silicate melt coexists with garnetite at 1100°С and with clinopyroxenite at 1150 and 1300°С. The peridotite–basalt–alkaline-aqueous–carbonate fluid at 4 GPa and 1400°C shows signs of critical relations between a carbonated silicate melt and a fluid. Reaction relations in the residual peridotite minerals with replacements of olivine ← orythopyroxene ← clinopyroxene ← potassic amphibole-type testify to a high chemical activity of the supercritical liquid. Experimental results suggest the existence of regions of partial melting (asthenospheric lenses) in the fluid-bearing upper mantle under supercritical conditions. These lenses contain near-solidus highly reactive supercritical liquids enriched in incompatible elements. Mantle reservoirs with supercritical liquids are geochemically similar to undepleted mantle and could serve as sources of magmas enriched in incompatible elements. The modal and cryptic upper mantle metasomatism under the effect of supercritical liquids leads to the refertilization of peridotite via enrichment of residual minerals in incompatible elements.

中文翻译：

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橄榄岩-玄武岩-流体体系的实验研究：亚临界和超临界Р-Т条件下的相关系

该论文报道了在压力高达4 GPa，温度高达1400°С时水合橄榄岩和玄武岩的部分熔融的实验数据，以及在碱性水-碳酸盐流体存在下橄榄岩-玄武岩的结合作为地幔的实验模型。俯冲的海洋原生质岩储层。在3.7–4.0 GPa和1000–1300°С的含水橄榄岩部分熔融时，在整个研究的压力和温度区间内观察到了临界关系。在含水玄武岩部分熔融时，在1000°С和3.7 GPa下记录了硅酸盐熔体与含水流体之间的临界关系。钠碱性硅酸盐熔体与石榴石在1100°C共存，斜铁辉石在1150和1300°C共存。在4 GPa和1400°C的橄榄岩-玄武岩-碱性水溶液-碳酸盐流体显示出碳酸盐硅酸盐熔体与流体之间存在临界关系的迹象。残余橄榄石矿物与橄榄石←邻苯二酚←斜靠石←钾闪石型的反应关系证明了超临界液体的高化学活性。实验结果表明，在超临界条件下，含流体的上地幔中存在部分熔融的区域（软流圈透镜）。这些镜片包含近固相的高反应性超临界液体，富含不相容元素。具有超临界液体的地幔储层在地球化学上类似于未耗尽的地幔，可以作为富含不相容元素的岩浆来源。