Interseismic deformation at the Nankai Trough, Japan, subduction zone
Interseismic deformation at the Nankai Trough, Japan, subduction zone
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日本南海海槽俯冲带的震间形变
DOI：
10.1029/92jb00810
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发表时间：
1992
影响因子：
--
通讯作者：
W. Thatcher
中科院分区：
文献类型：
--
作者：
J. C. Savage;W. Thatcher
根据1950-1985年的验潮记录，推测了1944年东南海（Ms = 8.0）和1946年南海岛（Ms = 8.2）地震后日本西南部沿海沿着的地震活动。虽然隆起率随地理位置而变化，但每个地点的时间相关性可以描述为指数衰减（时间常数为1.5年）瞬变和稳定的震间速率的叠加，该瞬变仅在震后的第一个十年内显著。稳定的震间抬升速率仅在1956-1985年期间被定义，但该抬升记录在时间上的线性使得可以合理地预期在震间周期的剩余时间（1980年）内的抬升将以相同的速率发生。此外，稳定的隆升速率的空间模式和幅度是合理的接近一个简单的位错模型的俯冲预测。然而，目前观测到的稳定抬升速率与前一个地震周期后半期大地水准测量推断的抬升速率并不一致。因此，要么是震后第一个十年后稳定的震间抬升速率的假设是错误的，要么是一次地震的应变积累模式不需要与同一段上的前一次地震相同。
Uplift along the coast of southwestern Japan following the 1944 Tonankai (Ms = 8.0) and 1946 Nankaido (Ms = 8.2) earthquakes has been inferred from the 1950–1985 tide gage records. Although uplift rates vary with geographic position, the temporal dependence at each site can be described as the superposition of an exponentially decaying (time constant ∼5 years) transient, significant only in the first decade postseismic, and a steady interseismic rate. The steady interseismic uplift rate is defined only over the 1956–1985 interval, but the linearity in time ofthat uplift record is such that uplift over the remainder of the interseismic cycle (∼80 years) might reasonably be expected to occur at the same rate. Moreover, the spatial pattern and magnitude of the steady uplift rate are reasonably close to those predicted by a simple dislocation model of subduction. However, the currently observed steady uplift rate is not consistent with the uplift rate inferred from geodetic leveling for the final half of the previous earthquake cycle. Thus, either the hypothesis of a steady interseismic uplift rate after the first decade postseismic is wrong or the strain accumulation pattern for one earthquake need not be the same as for the preceding earthquake on the same segment.