27 2 147 ~ 154 2011 6 EARTHQUAKE RESEARCH IN CHINA Vol. 27 No. 2 Jun. 2011 2011 5. 6 27 2 147 ~ 154 5. 6 42 830011 2008 8 30 5. 6 1 5. 6 70km 65km NE 5. 6 2 5. 6 10 - - 0. 05 99. 0% 5. 6 1001-4683 2011 02-0147-08 P315 A 0 1981 20 50 2004 1956 7. 2 1981 1981 Nakamura et al 2002 Li et al 1998 Korneev et al 2000 Schaff et al 2004 20 70 50 1993 1988 1985 1989 1997 2011-01-18 2009020103 1973 1999 E-mail longhaiying03@ yahoo. com. cn
148 27 2004 2005 2005 2006 2006 2008 1979 2006 2008 8 30 20 46 5. 6 1 2004 3 85. 1 E T 0 = γ 0 = 1 + R γ = nσ n nσ n ΔT 2 i - Σ n ΔT i T Pi - Σ n Σ n ΔT i T Pi Σ n ΔT i Σ n ΔT i 2 - nσ n - Σ n ΔT i 2 T PiΣ n T PiΣ n ΔT i 2 Σ n T Pi - T P ΔT i - ΔT i Σ n T Pi 槡 - T P 2 Σ n σ γ = γ 0-1 2 nσ n 槡 n - 2 [ nσ n ΔT i δt Pi ' 2 ΔT i 2 δt Pi ' = T Pi - T 0 - ΔT i γ 0-1 ΔT i ΔT i 2 2 - ΔT i - Σ n 2 ΔT i ] ΔT i = T Si - T Pi i T Pi i 1 2 3 4 5
2 5. 6 149 ( ) T Si i T P = 1 T n Σn Pi ΔT i = 1 ( n ) T 0 R γ σ γ 2 2. 1 ΔT Σn i γ 0 2006 2006 2006 11 23 5. 1 2007 7 20 5. 9 2008 8 30 5. 6 2009 1 25 5. 1 84 E 85. 1 E 2 1 1 1 1 2000 9 2001 1 3 2006 2008 8 30 5. 6 2. 2
150 27 2000 85. 1 E M L 2. 5 P S M L 2. 5 5 ~ 6 P S P S 2007 ~ 2009 10 734 M L 2. 5 676 2 2 2007 ~ 2009 10 M L 2. 5 3 3. 1 5. 6 2000 5. 6 100km 2006 1 ~ 2010 9 2007 10 ~ 2008 10 1. 708 0. 03 < 1. 708 1 > 1. 738 1. 708 ~ 1. 738 3 3 a 5. 6
2 5. 6 151 3 5. 6 1. 738
152 27 3 5. 6 2007 7 20 5. 9 2009 10 5. 6 3 b 5. 6 3 a 70km 65km NNE 5. 6 3 a 2 2007 9 21 M L 3. 0 2008 7 30 M L 2. 9 4 2007 9 2008 7 30 8 30 5. 6 2006 11 23 5. 1 2007 7 20 5. 9 4 5. 6 3. 2 0. 05 99. 0% 0. 0129 0. 03 99. 5% 1979 5 5 4 4. 1 5. 6 1 5. 6 70km 65km NNE 5. 6 2 5. 6 10
2 5. 6 153 5 5. 6 - - 4. 2 5. 6 - - - - 1981 50% 1981 2008 1981 1981 1997 5 535 ~ 541 2000 23 1 51 ~ 56 1989 2005 23 4 1 ~ 5 1981 1988 1989 1981 522 ~ 532 566 ~ 568 1985
154 27 2006 v P /v S 26 1 ~ 34 2004 24 1 163 ~ 169 1993 1979 1 2 1 ~ 8 2008 30 3 240 ~ 253 2005 7 1 40 ~ 45 2006-24 4 36 ~ 40 2006 26 4 133 ~ 137 Korneev V A McEvilly T V Karageorgi E D 2000 Seismological studies at Parkfield. VIII Modeling the observed travel time changes Bull Seismol Soc Amer 90 702 ~ 708. Li Y G Vidale J E Aki K et al 1998 Evidence of shallow fault zone healing after the 1992 M7. 5 Landers California earthquake Science 279 217 ~ 219. Nakamura A Hasegawa A Hirata N et al 2002 Temporal variations of seismic wave velocity associated with 1998 M6. 1 Shizukuishi earthquake Pure Appl Geophys 159 1183 ~ 1204. Schaff D P Beroza G C 2004 Coseismic and postseismic velocity changes measured by repeating earthquakes J Geophys Res 109 B10302 doi 10. 1029 /2004JB003011. Case analysis of wave velocities ratio abnormity before Hejing M5. 6 earthquake in Xinjiang Long Haiying Nie Xiaohong Tang Lanlan Earthquake Administration of Xinjiang Uygur Autonomous Region Urumqi 830011 China Abstract The authors used digital wave data of earthquakes in the middle of Tianshan mountains Xinjiang and Heda method of multi-stations to calculate changes of wave velocities ratio before and after the Hejing M5. 6 earthquake on August 30 2008. They obtained the result as follows 1In space it forms a low value area of ellipse before the Hejing earthquake with M5. 6. The half of the long axis is approximately 70km while that of the short axis is approximately 65km. And the trend of the ellipse is NE. The Hejing M5. 6 earthquake occurred in northwest part of the ellipse. 2Temporarily it appeared as low value abnormity of 10 months before the Hejing M5. 6 earthquake. Before this earthquake the value was obviously high. It forms a model of normal-fall-high value-earthquake. In the calculation process the error of wave velocities ratio is controlled in less than 0. 05 and the correlation coefficient reached above 99. 0%. Key words Hejing M5. 6 earthquake Wave velocities ratio Middle of Tianshan mountain Xinjiang