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在蓬莱赤山新生代碱性玄武岩中以包体形式产出的榴辉岩,由于受碱性玄武岩岩浆的热作用影响,发生了变质作用。致使榴辉岩的主要组成矿物石榴石发生了等化学组成的分解,形成尖晶石(X_(Mg)=0.51),斜长石(An=60～70)和富Al斜方辉石(X_(Mg)=0.71,Al_2O_312.6wt％)组成的集合体,达到了新的相平衡、其再平衡的温度为1200～1300℃;压力为9kbar。榴辉岩包体虽经变质作用,但没有改变它的REE丰度,它的典型的平坦型REE分配模式与碱性火山作用的富集LREE这样不相容元素的地幔区不同,它很可能是与碱性玄武岩岩浆无成因联系的随机捕虏的原始地幔物质。
The eclogite, which was produced by means of inclusion in Cenozoic alkaline basalt in Penglaizhan, was metamorphosed due to the thermal effect of alkaline basalt magma. Resulting in the decomposition of the mineral garnet, the major component of the eclogite, to form spinel (X_ (Mg) = 0.51), plagioclase (An = 60-70) and Al-rich orthopyroxene (Mg) = 0.71, Al_2O_312.6wt%), reaching a new phase equilibrium, the re-equilibrium temperature of 1200 ~ 1300 ℃; pressure of 9kbar. Although the metamorphism of the eclogite does not change its REE abundance, its typical flat REE distribution pattern is different from the mantle zone of incompatible elements such as LREE, which is enriched with alkaline volcanoes Is a random captive primitive mantle material associated with the originless basaltic magma.