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通过对采自福建明溪的幔源包体样品的详细研究,建立了该区上地幔的地温线,探讨其流变学特征。所获地温线高于大洋地温线,但稍低于中国东部和澳大利亚东南部地温线。由该地温线推导的壳幔边界为38 km左右,但尖晶石二辉橄榄岩在32 km左右即已开始出现,表明存在上地幔物质的底侵作用。同样,尖晶石二辉橄榄岩和石榴子石二辉橄榄岩包体平衡温度有所重叠,表明两者不是截然分开,其间存在有5～10 km的过渡带。包体的变形特征表明,该区上地幔曾发生过较强烈的变形作用,可能与软流圈的底辟上涌有关。它导致在60 km深度附近形成以高差异应力、高应变速率和低粘滞度为特征的剪切带。
Based on a detailed study of the mantle-derived inclusions collected from Mingxi, Fujian Province, the geothermal line of the upper mantle in the area was established and its rheological characteristics were discussed. The geothermal line was higher than the ocean geothermal line, but slightly lower than in eastern China and southeastern Australia geothermal line. The crust and mantle boundary derived from this geothermal line is about 38 km, but spinel lherzolites begin to appear at about 32 km, indicating that there is an underplating of upper mantle material. Similarly, the equilibrium temperatures of the spinel lherzolites and garnet lherzanites overlap, indicating that the two are not completely separated, with a 5 to 10 km transition between them. The deformation features of the enclaves show that the upper mantle in the area had a stronger deformation and may be related to the upwelling of the diapir. It results in the formation of shear bands characterized by high differential stress, high strain rates and low viscosity near a depth of 60 km.