地震地质 ›› 1990, Vol. 12 ›› Issue (4): 303-310.

• 科研简报 • 上一篇    下一篇

注水诱发地震的震源应力场和尾波衰减特征

赵根模, 杨港生   

  1. 天津市地震局
  • 收稿日期:1989-12-31 出版日期:1990-12-11 发布日期:2009-11-25

FOCAL STRESS FIELD BY WATER INJECTION-INDUCED EARTHQUAKES AND CHARACTERISTICS OF CODA WAVE ATTENUATION

Zhao Gen-mo, Yang Gang-sheng   

  1. Seismological Bureau of Tianjin City, Tianjin 300201
  • Received:1989-12-31 Online:1990-12-11 Published:2009-11-25

摘要: 利用区域性台网记录测定了任邱油田注水诱发地震的震源应力场和尾波衰减特征,结果表明地壳上层有很大水平应力,断层面解受注水井附近局部原生断层影响与华北现代应力场的优势破裂方向和错动方式有差别。地震应力降分布范围为0.2—3.0巴。平均尾波Q0值为75,属于地壳上部沉积岩层的正常情况,发现在时间上表现出与注水量增减有关的波动。在空间上表现出震群密集区Q0值较外围区偏低的特点。

关键词: 注水诱发地震, 尾波Q值, 应力降

Abstract: The focal mechanism solution,the coda wave value Q and the stress drop were obtained for the water injection-induced earthquakes with ML>2.0 which occurred in a period from sept. 1986,in the Renqiu oil field of North China.The obtained result indicates that the focal machanism of induced earthquakes under the effect of movement along the primary fault close to water injection well is different from that of natural earthquakes. The average coda wave value Q0 is 75 within the oil field which is smaller than that in the neardy areas. The stress drop by induced earthquakes changes from 0.2 to 3.0 bars. It shows that the stress background level in the oil field is not high.

Key words: Induced earthquake, Coda wave Q value, Stress drop