• 责任者：Li Yongli (Earthquake Administration of Yunnan Province ; Kunming 650224 ; China) ; Mao Huiling
• 刊名：Journal of Seismological Research
• 出版年：2009
• 卷期：32(1)
• 关键词：地震前兆 ; precursor ; 云南 ; Yunnan Province
• 页码：p.6-11
• 图表：2 illus., 1 table, 7 refs.
• 分类号：0500
• issnNo：ISSN1000-0666
• isbnNo：CN53-1062/P

Using the earthquake wave data recorded by Yunnan Regional Digital Network, the authors dynamically trace the anomalies of wave velocity ratio before 5 earthquakes with M≥5.8 in western Yunnan Province since 1998. The results show that the anomalous areas formed as a ellipse about 60~160 km long 1~3 years before the earthquakes, and the earthquakes usually occurred at the edge and meeting area of anomaly areas, or the range of 60 km from the periphery of low-value anomaly area. There are 11 high-value points (≥1.90) in the low-value areas of wave velocity ratio.