Development of the method for evaluation of subusurface fracture permeability by the multiplet-clustering analysis

本人开展了研究，以发展的方法来评估太阳表面裂缝的渗透性。我已经形成了评价渗透性的方法。本文在前人研究成果的基础上，指出了利用多重聚类分析确定的震源位置的时移分布来估计流体流动方向和渗透性裂缝系统的发育过程是可能的。我还发现，压力梯度以及在地热储层的水力刺激过程中的裂缝的临界孔隙压力，可以估计通过整合的构造应力场和裂缝的方向和时间推移分布的AE源位置，在那里我使用了在法国的Soultz HDR字段的诱发AE数据。我还指出，很难估计压力传播的速度，因为事件的数量是不够的数量和源不分布在整个水库。另一方面，我已经证明，流体在储层中的流动程度可以通过细化地震矩释放的增加率和震源面积的增加率来评估。本文还研究了地下破裂的动力学行为，（多重峰）和由多重峰的源位置所描绘的结构。因此，我在通过多重聚类分析精确确定的源位置的基础上开发了评估地热储中裂缝渗透率的方法，也暴露了评价的局限性。

I have carried out the research for the development of the method to evaluate the permeability of sunsurface fracture. I have taken form the method for the evaluation of permeability. On the basis of the results which obtained through the research before, I have shown that it is possible to estimate the direction of fluid flow and the growing process of permeable fracture system by the time lapse distribution of source location determined by the multiplet-clustering analysis. I have also revealed that the pressure gradient as well as the critical pore-pressure of fractures during the hydraulic stimulation of geothermal reservoir can be estimated by the integration of the tectonic stress field and the fracture orientation and the time lapse distribution of AE source location, where I used the induced AE data at the Soultz HDR field in France. I have also shown that it is difficult to estimate the velocity of pressure propagation because the number of events is insufficient number and the source does not distribute all over the reservoir. On the other hand, I have demonstrated that the degree of fluid flow in the reservoir can be evaluated by refining the increasing rate of seismic moment release and the increasing rate of source area. The dynamic behavior of subsurface fracture was also examined, where the relationship between the frequency band for identifying similar microearthquakes (multiplet) and the structures delineated by the source location of multiplet.As the results, I have developed the procedure to evaluate the fracture permeability in the geothermal reservoir on the basis of the precisely determined source location by the multiplet-clustering analysis, and also revealed the restriction on the evaluation.