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本文提出了金伯利岩岩浆作用的一种深成阶段底辟-裂隙模式.在地幔中由于化学对流形成了垂向延伸的热底辟上涌.这种底辟提供了在高压条件下裂隙形成和扩展的必要条件,即产生高的差异张应力和足够量的熔体.裂隙扩展是从200-300公里深处底辟顶部的岩浆房开始的.但只有在软流圈底辟体上部没有高程度部分熔融的地区,即只有在地盾区,裂隙才能到达地表.裂隙宽度大约是1-5米,裂隙中岩浆粘度η～10-10~3泊时,岩浆流动速度约为10-30米/秒,这样的速度足以使金伯利岩中的金刚石保持准稳态.岩浆的多次爆发特别是金伯利岩岩浆多次爆发可以由岩浆房围岩应力衰减过程来解释.本文也讨论了金伯利岩的侵入机理中挥发份的作用及受剪切的捕虏体的形成问题.
In this paper, a deep-stage diapirism-fractured pattern of kimberlite magmatism is proposed, and a vertical extension of the thermal diapir is formed due to chemical convection in the mantle.This diapir provides a solution to the formation of fractures under high pressure The necessary conditions for the extension are to produce high differential tensile stress and a sufficient amount of melt.The fracture propagation starts from the magma chamber at the top of the diabase 200-300 km deep, but only in the upper part of asthenospheric diapirs The degree of partial melting of the area, that is, only in the shield zone, the fissure to reach the surface.The fissure width is about 1-5 meters, fissure magma viscosity η ~ 10-10 ~ 3 poise, the magma flow rate of about 10-30 meters / S at a rate sufficient to maintain the quasi-steady state of the diamond in the kimberlite.The multiple outburst of magma, especially the kimberlite magma, can be explained by the stress attenuation process of the magma surrounding rock.In this paper, The Role of Volatiles in Invasion Mechanisms and the Formation of Sheared Xenoliths.