大陆板内塑性流动波与地震迁移（一）

PLASTIC-FLOW WAVS AND EARTHQUAKE MIGRATION IN CONTINETAL PLATE（Ⅰ）

大陆岩石圈下层的网络状塑性流动，通过能量的远距离传递，控制着板内地震的空间分布，而脉动式塑性流动波的传播决定了地震的迁移。根据地震时、空分布特征的分析结果，以喜马拉雅碰撞带为驱动边界的中东亚网络系统主要存在着两种塑性流动波，波速的沿网带分量分别约为１～７ｋｍ／ａ和１２～４５ｋｍ／ａ，边界起波的时间间隔平均为９３．７ａ和１０．８ａ，分别称之为“百年波”和“十年波”。塑性流动波的波峰带为地震的发生提供必要的能量背景条件。

The results of our studies show that the spatbial distribution of earthquakes in continent iscontrolled mainly by the plastic-flow network in the lower lithosphere which is reponsible for theintraplate long-range energy transmission, while the migration of earthquakes depends mainlyon the propagation of the plastic-flow waves similar to tidal bores advancing. Based on the analy-sis of the time-space distribution of earthquakes, in the central-eastern Asian plastic-flow net-work system with the Himalayan collision zone to be its driven boundary there are at least twosorts of plastic-flow waves, the 1st- and 2nd-velocity waves, or called ' century-wave'and'decade-wave ' respectively, which propagate with different velocities. The along-seismic-beltcomponents of the propagation velocities are about 1～7 km／a and 12～45 km／a, respectively,and the intervals of wave-originated times at the plate boundary for them are 68～133a（93.7aon average）and 7～18a（10. 8a on average）, respectively, showing quasi-periodicity. One mov-ing wave-crest belt is produced for each wave-originated stage, which provides a necessary condi-tion in energy background for the occurrence of earthquakes. The plastic-flow waves here are vis-coplastic deformation waves propagating mainly in the lower lithosphere and induced under thecombinative actions of plate boundary compression and intraplate gravity potential. The conceptof plastic-flow waves can not only reasonably explain the physical mechanism of earthquake mi-gration, but also gives an important basis for earthquake prediction considering the condition ofenergy background.