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Earthquake Hazards Program
Phase Data

Explanation of Parameters


     22 MAR 2009  ( 81)

     ot  = 11:48:29.10   +/-   0.37              TONGA REGION                    
     lat =     -22.800   +/-    9.9
     lon =    -174.874   +/-   10.2              MAGNITUDE 4.9 (GS)       
     dep =        35.0  (geophysicist)

     185 km (115 miles) SSE of NUKU'ALOFA, Tonga
     460 km (285 miles) ESE of Ndoi Island, Fiji
     470 km (290 miles) SSW of Neiafu, Tonga
     1845 km (1150 miles) NE of Auckland, New Zealand

     nph =   29 of  33    se = 1.14    FE=174                            B   

     error ellipse = (132.2,  0.0, 15.1; 42.2,  0.0, 10.9;  0.0,  0.0,  0.0)

 mb = 4.6 ( 18)  ML = 0.0 (  0)  mblg = 3.8 (  3)  md = 0.0 (  0)  MS = 0.0 (  0)

 sta  phase     arrival     res   dist azm    amp  per mag     amp  per mag  sta
 MSVF ePn     11:50:30.33   2.7    8.3 306 g:1.0-2 .95 2.9                   MSVF
 AFI  ePn     11:50:33.38  -7.7X   9.3  19 d:7.1+1     6.5X L:1.1-1 1.0 4.7X AFI 
                                           g:1.0-1 1.0 3.9  b:1.0+2 1.0 5.9X
 RAR  ePn     11:51:38.63  -7.7X  14.1  86 g:6.6-2 .95 4.0  b:6.6+1 .95 5.3X RAR 
 URZ  eP      11:52:22.97   0.5   16.9 202 b:7.9+1 1.5 4.6                   URZ 
 STKA eP      11:55:54.42  -2.0   39.5 247 b:4.5+0 1.6 4.0                   STKA
 AS31 eP      11:56:52.99  -3.2X  46.9 258                                   AS31
 WRAB eP      11:56:55.05  -3.7X  47.2 263 b:3.2+0 .70 4.4                   WRAB
 FORT eP      11:57:28.09  -0.4   51.1 248 b:1.0+1 .58 5.0                   FORT
 FITZ eP      11:58:00.18  -1.7   55.6 263 b:1.6+0 .60 4.2                   FITZ
 VNDA eP      11:58:05.07   2.0   55.9 186 b:4.2+0 .91 4.5                   VNDA
 QSPA eP      11:59:20.81   0.7   67.3 180 b:1.4+1 1.0 5.0                   QSPA
 ISA  eP      12:00:29.68   0.5   78.9  44 b:7.6+0 1.2 4.6                   ISA 
 CMB  eP      12:00:30.44  -0.3   79.2  41 b:6.9+0 .99 4.6                   CMB 
 GSC  eP      12:00:33.98   0.1   79.8  45 b:6.6+0 1.1 4.5                   GSC 
 CCUT eP      12:00:52.86   0.0   83.3  45 b:6.2+0 1.2 4.6                   CCUT
 ELK  eP      12:00:56.10  -0.2   84.0  41                                   ELK 
 SNAA eP      12:01:03.08  -0.6   85.6 177 b:7.2+0 .90 4.9                   SNAA
 LAZ  eP      12:01:05.65   0.1   85.8  50 b:8.1+0 1.6 4.7                   LAZ 
 SRU  eP      12:01:07.55   1.1   86.1  45 b:6.0+0 1.0 4.7                   SRU 
 LPM  eP      12:01:07.86   0.8   86.2  50 b:5.3+0 1.4 4.6                   LPM 
 ANMO eP      12:01:09.21  -0.1   86.6  50 b:6.2+0 1.1 4.8                   ANMO
 GDL2 eP      12:01:10.00   0.1   86.8  53                                   GDL2
 TRF  eP      12:01:13.39  -2.4   88.1  11 b:1.4+2 2.6 5.8X                  TRF 
 COLA eP      12:01:22.70  -1.0   89.9  11 b:4.3+0 .83 4.8                   COLA
 CHTO eP      12:01:43.23   0.4   93.7 289 b:2.7+0 1.0 4.6                   CHTO
 KIEV ePKPdf  12:08:04.39  -0.5  146.4 332                                   KIEV
 SUW  ePKPdf  12:08:04.47   0.5  146.0 341                                   SUW 
 AK01 ePKPdf  12:08:04.68  -0.2  146.4 332                                   AK01
 AK02 ePKPdf  12:08:04.91   0.0  146.5 332                                   AK02
 MALT ePKPdf  12:08:09.17   1.7  147.6 306                                   MALT
 BR131ePKPbc  12:08:16.45  -1.1  150.5 312                                   BR13
 BUR08ePKPbc  12:08:16.77  -0.3  150.5 332                                   BUR0
 MORC ePKPbc  12:08:18.62  -0.4  151.4 343                                   MORC



 Generated 2009 MAR 22 at 12:43 UTC

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


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