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摘要：基于大量地幔包体的岩石学和地球化学研究，推断在大陆岩石圈地幔内部发育着熔体与橄榄岩反应，以华北克拉通岩石圈地幔最具典型。依据地幔捕虏体的矿物交代特征和相关元素地球化学指标，华北克拉通岩石圈地幔发育着硅酸盐熔体与橄榄岩反应（如吉林辉南、安徽女山、山东山旺、河北汉诺坝、内蒙古集宁、河北符山等地区）和碳酸岩熔体与橄榄岩反应（如河南鹤壁、山东铁铜沟、河南信阳等地区）。已有的熔体与橄榄岩反应高温高压实验研究的初始熔体也可以归为硅酸盐熔体和碳酸岩熔体两大类。这些实验研究为探讨异剥橄榄岩、纯橄岩、高镁安山岩、高镁埃达克质岩等特殊岩石成因及岩石圈地幔组成的变化提供了直接证据。今后通过进一步的熔体与橄榄岩反应高温高压实验研究，建立反应产物特征与初始熔体性质、组成的对应关系，是揭示华北克拉通岩石圈地幔从古老难熔型向“年轻”饱满型演化的重要途径。

关键词：实验岩石学；熔体与橄榄岩反应；高温高压实验；岩石圈地幔；硅酸盐熔体；碳酸岩熔体；华北克拉通

中图分类号：P589.1文献标志码：A

Abstract： It has been concluded that there are meltperidotite reactions occurring within continental lithospheric mantles from the petrological and geochemical studies on a large number of mantle xenoliths. This case is especially typical in the lithospheric mantle of North China Craton. Based on the mineralogical metasomatic characteristics in mantle xenoliths and the related element geochemical signatures， it is identified that the melt reacted with peridotite within the lithospheric mantle of North China Craton is silicate melt such as in Huinan of Jilin， Nushan of Anhui， Shanwang of Shandong， Hannuoba of Hebei， Jining of Inner Mongolia and Fushan of Hebei， and carbonatite melt such as in Hebi of Henan， Tietonggou of Shandong and Xinyang of Henan. The starting melts used in previous reaction experiments under hightemperature and highpressure conditions can be also classified into silicate and carbonatite melts. The experimental studies have provided direct evidence for the origin of some special rocks， such as wehrlite， dunite， highMg andesite， highMg adakite， and for the compositional change in lithospheric mantle. Further experimental study on meltperidotite reaction under hightemperature and highpressure conditions， in which the characteristic of run product is correlated with the property and composition of the starting melt， is an important way to reveal lithospheric mantle evolution of North China Craton from ancient refractory to “young” fertile.

Key words： experimental petrology； meltperidotite reaction； experiment under hightemperature and highpressure conditions； lithospheric mantle； silicate melt； carbonatite melt； North China Craton

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图件引自文献[15]

岩石圈地幔是地球内部连接地壳和软流圈的重要圈层，是岩石圈的主体。大陆岩石圈地幔以莫霍面为界，下伏于大陆地壳，上覆于软流圈。特殊的位置决定了大陆岩石圈地幔对大陆地壳和整个大陆岩石圈的性质和组成有重要影响。古老的克拉通型岩石圈地幔主要由富Mg的方輝橄榄岩组成，其主要矿物是橄榄石和斜方辉石[17]。根据前人对大陆岩石圈地幔的研究，南非Debeers、Jagersfontein及Bultfontein等地金伯利岩区中常出现主要含有金云母、角闪石和富含不相容元素的FeTi氧化物等交代矿物[814]。这些交代矿物的出现意味着富含K、Ba、Ti、Zr、Nb和稀土元素（REE）等不相容元素的熔体与地幔橄榄岩发生了反应，改变了岩石圈地幔的组成。前人通过对中国华北克拉通古生代金伯利岩、中生代玄武岩或闪长岩、新生代玄武岩所携带的地幔岩包体系统的岩石学、矿物学和地球化学研究（图1），推断在华北克拉通岩石圈地幔演化过程中较为广泛地发育着橄榄岩与不同性质熔体的反应。