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Earthquake Hazards Program
Phase Data

Explanation of Parameters


     22 APR 2009  (112)

     ot  = 15:18:21.60   +/-   0.86              TONGA                           
     lat =     -17.279   +/-    5.7
     lon =    -174.452   +/-    4.3              MAGNITUDE 4.7 (GS)       
     dep =       216.3   +/-    8.0   

     160 km (100 miles) NNW of Neiafu, Tonga (pop 3,000)
     165 km (100 miles) SSW of Hihifo, Tonga
     435 km (270 miles) N of NUKU'ALOFA, Tonga
     2415 km (1500 miles) NNE of Auckland, New Zealand

     nph =  100 of 103    se = 0.79    FE=173                            A   

     error ellipse = (251.3, 77.7, 12.5;152.6,  1.9,  9.4; 62.2, 12.1,  4.9)

 mb = 4.7 ( 61)  ML = 0.0 (  0)  mblg = 0.0 (  0)  md = 0.0 (  0)  MS = 0.0 (  0)

 sta  phase     arrival     res   dist azm    amp  per mag     amp  per mag  sta
 AFI  ePn     15:19:17.12  -9.8X   4.2  38 d:4.2+2     6.0X L:1.5+1 .55 5.8X AFI 
      eS      15:19:59.14  S res = -19.2X  g:1.1+1 .90 5.4X
 MSVF ePn     15:20:06.48   2.2    7.2 265 d:1.5+2     6.3X L:1.3-1 1.0 4.3X MSVF
                                           g:1.1-1 1.0 3.8X b:1.1+2 1.0 5.0 
 FUNA ePn     15:20:48.28  -1.0   10.7 324 g:9.5-1 1.5 4.8X b:9.5+2 1.5 5.9X FUNA
 RAR  ePn     15:21:36.57   0.7   14.4 108 g:2.3-1 1.2 4.5X b:2.3+2 1.2 5.4  RAR 
 DZM  qP      15:22:23.37   0.2   18.6 252 g:3.7-2 1.2 3.9X b:5.9+1 1.4 4.9  DZM 
 URZ  eP      15:22:58.51  -1.4   22.2 198 g:1.3-1 .78 4.8X b:1.3+2 .78 5.5  URZ 
 HNR  eP      15:23:34.51  -1.1   26.1 284 g:1.4-1 1.1 4.7X b:1.4+2 1.1 5.5  HNR 
 KHZ  eP      15:23:42.28  -1.8   27.1 200 g:3.3-2 .90 4.2X b:2.7+1 .78 5.0  KHZ 
 RPZ  eP      15:24:01.04  -0.8   29.1 202                                   RPZ 
 CTAO iPc     15:25:11.80  -1.2   37.3 259 b:2.9+1 .90 4.9                   CTAO
 PMG  eP      15:25:20.24   0.2   38.1 277 b:3.0+1 .85 4.9                   PMG 
 COEN eP      15:25:42.63  -0.3   40.9 268 b:2.0+2 1.1 5.5                   COEN
 STKA eP      15:25:54.05   0.3   42.2 241 b:1.2+1 .95 4.3                   STKA
 BBOO eP      15:26:31.82   0.4   47.0 241 b:3.8+2 1.0 5.7X                  BBOO
 WRAB eP      15:26:41.68  -1.0   48.4 258 b:2.2+1 .60 4.7                   WRAB
 AS31 eP      15:26:43.46  -0.3   48.6 253                                   AS31
 FITZ eP      15:27:44.16   0.0   56.9 259 b:1.1+1 1.0 4.5                   FITZ
 MBWA eP      15:28:18.53   0.0   61.9 255 b:4.2+1 1.1 5.1                   MBWA
 KAPI eP      15:28:41.28  -0.5   65.4 272 b:2.6+1 .85 5.0                   KAPI
 MAJO eP      15:29:08.17  -0.1   69.7 321 b:1.6+1 .90 4.7                   MAJO
 PEA0BeP      15:29:33.73  -0.1   74.1 343                                   PEA0
 ISA  eP      15:29:37.58  -0.2   74.7  44 b:1.1+1 1.3 4.4                   ISA 
 WDC  eP      15:29:39.07  -0.6   75.1  38 b:4.3+0 .95 4.2                   WDC 
 GSC  eP      15:29:43.16   0.1   75.6  46 b:1.1+1 1.2 4.5                   GSC 
 YBH  eP      15:29:43.68   0.3   75.7  37 b:1.1+1 .85 4.6                   YBH 
 BEKR eP      15:29:44.25  -0.7   75.9  40 b:4.3+0 1.0 4.1                   BEKR
 HUMO eP      15:29:45.63   0.2   76.1  37 b:1.1+1 .98 4.5                   HUMO
 NV11 eP      15:29:47.91   0.0   76.5  42                                   NV11
 LDFC eP      15:29:49.38   0.4   76.7  46 b:2.7+1 1.2 4.8                   LDFC
 MOD  eP      15:29:51.83  -0.1   77.2  38 b:1.3+1 1.1 4.5                   MOD 
 WVOR eP      15:29:58.61  -0.5   78.5  39 b:9.3+0 1.0 4.4                   WVOR
 RSO  eP      15:30:02.54  -1.1   79.4  11 b:3.5+1 .94 5.1                   RSO 
 SEW  eP      15:30:04.22  -0.8   79.7  12 b:2.4+1 .92 4.9                   SEW 
 WUAZ eP      15:30:05.32   0.7   79.5  48                                   WUAZ
 HAWA eP      15:30:08.79  -0.1   80.4  35 b:5.2+0 .93 4.2                   HAWA
 BMO  eP      15:30:09.93  -0.9   80.7  37 b:6.7+0 1.2 4.2                   BMO 
 MSU  eP      15:30:10.13   0.3   80.5  45 b:3.7+0 .76 4.2                   MSU 
 MVU  eP      15:30:10.65   1.0   80.4  45                                   MVU 
 PMR  eP      15:30:10.73  -1.8   81.2  12 b:2.2+1 1.0 4.8                   PMR 
 DUG  eP      15:30:11.79  -0.2   80.9  43                                   DUG 
 DIV  eP      15:30:13.76  -0.5   81.4  14 b:4.3+1 .92 5.2                   DIV 
 BMRM eP      15:30:14.43  -0.4   81.6  14 b:3.9+1 1.2 5.0                   BMRM
 HLID eP      15:30:16.34   0.2   81.7  40 b:1.5+1 1.4 4.5                   HLID
 SRU  eP      15:30:17.31   0.1   81.9  45                                   SRU 
 DAU  eP      15:30:18.73   0.6   82.0  43                                   DAU 
 TRF  eP      15:30:18.75  -1.8   82.6  11 b:2.3+1 .78 5.0                   TRF 
 LAZ  eP      15:30:18.90   0.8   82.0  50 b:1.1+1 1.7 4.3                   LAZ 
 HWUT eP      15:30:19.60  -0.5   82.5  42 b:3.1+2 .88 6.0X                  HWUT
 BNM  eP      15:30:20.10   0.6   82.3  51 b:5.6+0 1.0 4.2                   BNM 
 LPM  eP      15:30:20.49   0.7   82.4  51 b:1.1+1 1.1 4.5                   LPM 
 PV04 eP      15:30:21.46   0.4   82.6  46                                   PV04
 PV01 eP      15:30:21.77   0.1   82.7  47                                   PV01
 TNA  eP      15:30:21.88   1.2   82.7   3 b:3.6+1 1.3 4.9                   TNA 
 PAX  eP      15:30:22.02  -1.0   83.2  13 b:4.7+0 .78 4.3                   PAX 
 ANMO eP      15:30:22.06   0.2   82.8  50 b:1.5+1 1.2 4.6                   ANMO
 SKAG eP      15:30:22.12   0.8   82.8  19 b:8.9+0 .84 4.5                   SKAG
 MCK  eP      15:30:22.12  -0.8   83.1  11 b:4.3+1 .88 5.2                   MCK 
 MENT eP      15:30:24.57  -0.2   83.5  14                                   MENT
 GDL2 eP      15:30:24.58   0.8   83.1  53 b:5.4+0 .72 4.4                   GDL2
 MCMT eP      15:30:24.65   0.0   83.3  39 b:5.8+0 .98 4.3                   MCMT
 AHID eP      15:30:24.83   0.2   83.3  42 b:9.6+0 .98 4.5                   AHID
 DLBC eP      15:30:26.28  -0.2   83.8  22                                   DLBC
 BSMT eP      15:30:26.30  -0.9   83.9  36 b:2.4+0 .72 4.1                   BSMT
 TPAW eP      15:30:26.94  -0.1   83.8  41 b:1.6+1 1.0 4.7                   TPAW
 SNOW eP      15:30:27.99   0.4   83.9  41 b:1.5+1 .88 4.8                   SNOW
 MOOW eP      15:30:28.01  -0.3   84.1  41 b:7.3+0 1.3 4.3                   MOOW
 CHMT eP      15:30:28.05  -1.0   84.2  37 b:3.5+0 1.0 4.0                   CHMT
 IMW  eP      15:30:28.13  -0.1   84.0  41 b:1.4+1 .98 4.7                   IMW 
 COLA eP      15:30:28.30  -0.8   84.4  11 b:5.3+1 .85 5.3                   COLA
 BOZ  eP      15:30:29.05  -1.3   84.5  39 b:1.1+1 1.2 4.5                   BOZ 
 QLMT eP      15:30:29.29   0.3   84.2  40 b:2.2+0 1.1 3.8                   QLMT
 SMCO eP      15:30:29.89  -0.1   84.3  46                                   SMCO
 YMR  eP      15:30:31.08   1.1   84.4  40                                   YMR 
 EGAK eP      15:30:35.19  -0.3   85.7  14 b:2.6+1 .95 5.0                   EGAK
 COLD eP      15:30:37.02  -0.8   86.1   9 b:1.7+1 1.2 4.7                   COLD
 JCT  eP      15:30:38.06   0.0   86.0  57 b:8.0+0 .88 4.6                   JCT 
 IPM  eP      15:30:40.28   1.3   86.1 276 b:4.2+1 1.1 5.2                   IPM 
 CM31 eP      15:31:09.77   2.2   92.2 289 b:5.3+0 .88 4.6                   CM31
 CHTO eP      15:31:09.86   1.8   92.4 289 b:7.8+0 .80 4.8                   CHTO
 ULN  eP      15:31:20.53   0.1   95.2 319 b:2.8+0 .90 4.5                   ULN 
 MK31 ePKiKP  15:36:29.99   0.0  111.4 314                                   MK31
 TKM2 ePKPdf  15:36:39.44   0.1  116.1 310                                   TKM2
 AAK  ePKPdf  15:36:40.71  -0.1  116.9 309                                   AAK 
 BRVK ePKPdf  15:36:43.75  -0.1  118.8 321                                   BRVK
 KKAR ePKPdf  15:36:46.10  -0.1  119.8 310                                   KKAR
 KBL  ePKPdf  15:36:48.95  -0.5  121.2 300                                   KBL 
 ABKARePKPdf  15:36:58.44   0.7  126.0 319                                   ABKA
 KMBO ePKPdf  15:37:32.01  -0.3  143.8 243                                   KMBO
 MALT ePKPdf  15:37:33.12   0.6  144.4 313                                   MALT
 BUR08ePKPdf  15:37:35.59   1.2  145.7 336                                   BUR0
 MORC ePKPbc  15:37:36.26  -0.1  146.2 346                                   MORC
 GRFO ePKPdf  15:37:36.79  -0.1  147.3 353                                   GRFO
 BR131ePKPdf  15:37:37.36   0.6  146.9 318                                   BR13
      ePKPbc  15:37:39.19   0.2X
 PSZ  ePKPbc  15:37:39.94   0.4  147.3 342                                   PSZ 
 KHC  ePKPbc  15:37:40.91   0.6  147.6 350                                   KHC 
 WLF  ePKPbc  15:37:41.72   1.2  147.7 359                                   WLF 
 BFO  ePKPbc  15:37:44.45   0.6  148.9 356                                   BFO 
 ECH  ePKPbc  15:37:44.84   0.5  149.1 358                                   ECH 
 CSS  ePKPbc  15:37:46.51   0.6  149.6 311                                   CSS 
 TUE  ePKPbc  15:37:49.02   0.6  150.7 355                                   TUE 
 SSB  ePKPbc  15:37:51.91   0.5  152.1   2                                   SSB 



 Generated 2009 APR 22 at 20:27 UTC

Preliminary Earthquake Report
U.S. Geological Survey, National Earthquake Information Center
World Data Center for Seismology, Denver


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