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迄今已有的实验资料促使许多地质工作者提出:关于海相火山岩中占优势的低钾拉斑玄武岩,不能直接在高压下从上地幔的火成岩基底熔出的结论。鉴于这种情况,有许多作者推测:洋中脊的拉斑玄武岩是在不深处(～30公里)形成。因为根据实验资料所知,在这样的压力下,只是部分拉斑玄武岩能从橄榄岩中熔出。据(?)等人的计算说明,在这一深度橄榄岩熔解而形成高镁的熔岩,即这熔岩被队为是海洋拉斑玄武岩的原岩。因此,最近几年来有大量的文献论述有关具体的拉斑玄武岩系的原始
The experimental data available to date have led many geologists to conclude that the low-potassium tholeiite basalts, which are dominant in marine volcanic rocks, can not be directly melted from the igneous basement of the upper mantle under high pressure. In view of this situation, many authors speculate that tholeiites in the mid-ocean ridge are formed not deep (~ 30 km). Because according to experimental data, under such pressure, only part of tholeiite can be melted from peridotite. According to the calculation of (?) Et al., At this depth the peridotite melts to form high-magnesium lava, ie the lava is being marketed as the original rock of marine tholeiitic basalts. Therefore, in recent years a large number of literatures have dealt with the primitive