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假设圣安德烈斯断层(加州)中存在高孔隙压力流体,并用其来解释断层的主动性失稳,这或许直接影响着对地震发生机理的认识。但最近在位于加州东部圣安德烈斯断层上的钻探(SAFOD,San Andreas Fault Observatory at Depth)中,未发现存在高孔隙压力流体的相关证据[1]。假如没有高孔隙压力普遍存在的证据,这将影响我们对圣安德烈斯断层或其他活断层上地震发生机理的认识。然而,笔者认为圣安德烈斯断层深钻现有的证据,尚不足以否定高孔隙压力流体存在的假说。要充分认识断层中孔隙压力的特征,还需要在圣安德烈斯断层的钻孔上进行长期监测。以上分析结果或许对解释其他活断层钻探项目结果有所帮助。
The assumption of high pore pressure fluids in the San Andreas Fault (California) and their use to account for the instability of the faults may have a direct impact on the understanding of the underlying mechanism of the earthquake. However, no evidence of high pore pressure fluids has been found recently in the San Andreas Fault Observatory at Depth (SAFOD) drilling in the eastern part of California [1]. Without the ubiquitous evidence of high pore pressure, this will affect our understanding of the mechanism of earthquakes on the San Andreas Fault or other active faults. However, I believe that the evidence available for deep drilling of the San Andres fault is not enough to deny the hypothesis of the presence of highly porous fluids. To fully understand the characteristics of pore pressure in faults, long-term monitoring on the boreholes of the San Andreas fault is also required. The above analysis may help explain the results of other active fault drilling projects.