组合坚固体应变扰动及波速异常的破裂前兆特征研究

地震 ›› 1999, Vol. 19 ›› Issue (4): 331-337.

组合坚固体应变扰动及波速异常的破裂前兆特征研究

许昭永¹⁾, 王彬¹⁾, 杨润海¹⁾, 赵晋明¹⁾, 梅世蓉²⁾

1)中国昆明 650041云南省地震局;
2)中国北京 100036中国地震局分析预报中心

收稿日期:1998-10-28 修回日期:1999-01-10 出版日期:1999-10-31 发布日期:2022-09-23
作者简介:许昭永,男, 1943年4月出生,研究员,主要从事实验地球物理学研究工作。

STRAIN SHAKING AND WAVE VELOCITY ANOMALY AND STUDIES ON FRACTURING PRECURSORY FEATURES OF COMBINED STRONG BODY

Xu Zhaoyong¹⁾, Wang Bin¹⁾, Yang Runhai¹⁾, Zhao Jinming¹⁾, Mei Shi rong²⁾

1) Seis mological Bureau of Yunnan Province, Kunmi ng 650041，China;
2) Center for Analysis and Prediction, CSB, Beijng 10036, China

Received:1998-10-28 Revised:1999-01-10 Online:1999-10-31 Published:2022-09-23

摘要/Abstract

摘要： 研究了高、低强度3段拼合岩石样品在单轴压缩和双轴单面直接剪切时的破裂特征及突发应变扰动与波速异常的破裂前兆。从分别置于高、低强度段上的应变变化看,在整个样品破裂前,低强度段(弱岩)先出现突发扰动,高强度段(强岩)后出现突发扰动。从分别穿过高、低强度段上的波速变化看,低强度段波速先出现下降,高强度段后出现下降。主破裂后明显的裂缝贯穿整个拼合岩样。进而讨论了坚固体孕震模式(主破裂前)的突发性应变前兆与波速异常的时空特征。

关键词: 拼合岩样, 坚固体破裂, 应变扰动, P波走时

Abstract: Under the conditions of uniaxial compression and biaxial single-Hateral direct shearing，the authors have studied fractuning features, sudden strain shaking and wave velocity anomalies for fracturing precursors of the 3-segment-com bined sample with high and low strengths. Viewing from the variations of strains in high and low strengths, there appears sudden shaking first in the segment with low strengths (weak rock)，and thenin the segment with high strength (strong rock), before the whole sample fracturing. Viewing from variations of wave velocities passing through segments with high and low strengths, there appears decrease of wave velocities first in the segment with low strength, and then in the segment with high strength. The fissures pass throughout the whole-segm ented sa mple obviously after the main fracture. Further, the authors have discussed spatial-temporal features of the sudden strain precursor and wave velocity anomalies in the seismogenic model of strong body (before main fracture).

Key words: Segmented rock sample, Fracture of strong body, Strain shaking, Ptravel timel

许昭永, 王彬, 杨润海, 赵晋明, 梅世蓉. 组合坚固体应变扰动及波速异常的破裂前兆特征研究[J]. 地震, 1999, 19(4): 331-337.

Xu Zhaoyong, Wang Bin, Yang Runhai, Zhao Jinming, Mei Shi rong. STRAIN SHAKING AND WAVE VELOCITY ANOMALY AND STUDIES ON FRACTURING PRECURSORY FEATURES OF COMBINED STRONG BODY[J]. EARTHQUAKE, 1999, 19(4): 331-337.