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根据2002年迪纳利断层地震前后的主应力方向及应力变化,采用一种新方法得到了沿该地震破裂的断层在空间上平均的绝对偏应力张量。应力是在沿迪纳利断层在3个区域估计的,其中一个区域还包括苏西特纳冰川断层,一个区域沿托茨昌达断层。估计的地震前分解到地震破裂断层上的空间平均剪切应力约为1MPa到约4MPa。得到的所有这些区域地震后沿断层的剪切应力几乎为零(0±1MPa)。这些结果表明:沿走向数十千米的平均偏应力水平较低,地震时的应力下降较为完全。
According to the principal stress direction and stress change before and after the 2002 Denali Fault Earthquake, a new method is used to obtain the spatially averaged absolute deviatoric stress tensor of the fault ruptured along the earthquake. Stress is estimated in three areas along the Denali Fault, one of which also includes the Susitna Glacier fault and one along the Totz Prayer Fault. The estimated average shear stress on the rupture faulting before the earthquake is about 1 MPa to about 4 MPa. The shear stress along the faults after these earthquakes was almost zero (0 ± 1 MPa) in all of these areas. These results show that the mean deviatoric stress level is lower along the tens of kilometers and the stress drop during the earthquake is more complete.