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本文提出的超镁铁质岩包体的全岩成分,矿物化学和微量元素地球化学的全部资料表明,大部分二辉橄榄岩包体代表饱满的地幔样品,而黑色二辉岩包体代表来自下部地壳的麻粒岩样品。二辉橄榄岩包体在980—1120℃有限的温度范围内平衡,但是平衡压力在计算的温度下变化相当大(12.5—24千巴)。黑色二辉岩包体有相对低的平衡条件(850—950℃,8千巴)。和大洋、地盾地温相比,在深度小于100公里时,由二辉橄榄岩体包体所确定的古地温有陡得多的斜率。可以推断最少亏损的地幔可能直接位于被研究的地区之下。
All the data of the whole rock, mineral chemistry and trace element geochemistry of the ultramafic intrusive inclusions presented in this paper show that most of the imlolite inclusions represent plump mantle samples and the black dolomite inclusions represent Lower crust of granulite samples. The lherzolitic inclusions are balanced over a limited temperature range of 980-1120 ° C, but the equilibrium pressure varies considerably at the calculated temperature (12.5-24 kbar). The black dolomite inclusions have relatively low equilibrium conditions (850-950 ° C, 8 kPa). Compared with the geotemperature of the ocean and the earth’s shield, the paleo-geothermal temperature determined by the lherzolite inclusions is much steeper at a depth of less than 100 km. It can be concluded that the least depleted mantle may be directly under the area under study.