MLOC Summary File

Summary File

This section describes the summary file (~.summary), one of the most important output files, which is produced by every run of mloc. It has several sections:

The header section lists basic information and many of the parameters that were set for the run. Its use is mainly forensic: if you are inspecting a relocation by someone else or if you go back after some time to review one of your own runs, the information in the header section will provide answers to most of the basic questions about how it was done. Here is an example, from the Ridgecrest, California cluster (ridgecrest3.1):

 Program: mloc v10.4.7, release date 7/14/2019
 Run: ridgecrest3.1
 Author: EBergman
 Date: 20190824 132053.523
 Travel times: ak135 (ridgecrest3/ridgecrest.cr)
 Lg travel times:   0.03 +  31.68 * delta
 T-phase travel times:  15.00 +  75.00 * delta
 Station elevation correction: on (focal depth referenced to geoid in direct calibration)
 Supplemental station file: ridgecrest3/ridgecrest_stn.dat
 Data flags used: on 
 Residuals weighted by reading errors: on 
 Assume perfect theoretical TTs for hypocentroid (ttsprd = 0): off
 Reading errors: ridgecrest3/ridgecrest2.42.rderr
 Minimum allowed reading errors:  0.10 (local) / 0.15 (general) / 1.00 (depth phases)
 Reading errors for local phases: Not set
 Cluster vector fudge factor (non-gaussian):   0.00
 Travel time spread: ridgecrest3/ridgecrest2.42.ttsprd
 Windowing:   3.0  4.0
 Hypocentroid bias correction: on
 Data flags: used
 Starting locations: ridgecrest3/ridgecrest2.42.hdf_dcal
 Direct calibration: on
 Distance ranges:
    Hypocentroid   :    0.0   0.8
    Cluster vectors:    0.0 180.0
 Hypocentroid location parameters: (lat, lon,      , origin time)

Hypocentroid Section

This section tracks changes in the hypocentroid of the cluster through the relocation.

                         TIME        LATITUDE     LONGITUDE       DEPTH           E**2/NSTA   SHAT  PRMAX  DELT PRES FLAG
 START                14:18:47.53      35.787      -117.570        15.0

 ITER 0                      0.00 S    -0.02 KM       0.01 KM       0.00 KM     104.0/ 1197   0.89    4.0  9235  656 1915
 ITER 1                      0.00 S     0.02 KM       0.00 KM       0.00 KM     104.8/ 1197   0.89    4.0  9235  609 1915
 ITER 2                      0.00 S     0.01 KM       0.00 KM       0.00 KM     104.2/ 1197   0.89    4.0  9235  608 1915

 CUMULATIVE                  0.00 S     0.01 KM       0.01 KM       0.00 KM    AZIM =    0 DEG    DIST =  0.0 KM

 SOLUTION             14:18:47.53      35.787      -117.570        15.0
 STANDARD ERRORS             0.02 S     0.001 DEG     0.002 DEG     0.00 KM    ELLIPSE: -33.9 DEG   0.3 AND    0.3 KM

Hypocentroid Shift Section

This section of a ~.summary file only exists in the case of indirect calibration. In that case, after the relocation is converged, using either an uncalibrated or direct calibration methodology, the locations of events that have been declared as calibration events in the command file are compared with the calibration locations and an optimal shift of the entire cluster in space and time is calculated to bring the cluster into best agreement with the calibration data. In this section the shift required for each calibration event is listed and the final optimal shift. Much more detail about this process is provided in the Cal file (~.cal) file that is produced when indirect calibration is invoked.

The following example is taken from a cluster consisting nuclear tests conducted by the United States at Bikini Atoll:

 SHIFT                      -0.25 S    -0.032 DEG     0.072 DEG     0.00 KM    AZIM =  114 DEG    DIST =  8.6 KM
 CALIBRATED           16:30:20.01      11.670       165.324         0.0

 Calibration event correction vectors (weights):

 EVENT   1  19540228.1845.00  -0.08(1.39)  -0.021(1.51)   0.058(1.51)   0.00(1.00) AZIM =  110 DEG    DIST =  6.7 KM
 EVENT   2  19540326.1830.00  -0.28(1.47)  -0.027(1.75)   0.088(1.75)   0.00(1.00) AZIM =  107 DEG    DIST = 10.0 KM
 EVENT   3  19540425.1810.00  -0.66(0.94)  -0.027(0.90)   0.069(0.90)   0.00(1.00) AZIM =  112 DEG    DIST =  8.1 KM
 EVENT   4  19540504.1810.00  -0.23(1.35)  -0.033(1.49)   0.050(1.49)   0.00(1.00) AZIM =  124 DEG    DIST =  6.6 KM
 EVENT   5  19560527.1756.00  -0.48(0.71)  -0.041(0.91)   0.060(0.91)   0.00(1.00) AZIM =  125 DEG    DIST =  8.0 KM
 EVENT   6  19560710.1756.00  -0.47(0.86)  -0.058(0.89)   0.077(0.89)   0.00(1.00) AZIM =  128 DEG    DIST = 10.5 KM
 EVENT   7  19560720.1746.00  -0.02(0.59)  -0.021(0.31)   0.114(0.31)   0.00(1.00) AZIM =  100 DEG    DIST = 12.6 KM
 EVENT   8  19580511.1750.00  -0.14(0.65)  -0.061(0.35)   0.114(0.35)   0.00(1.00) AZIM =  119 DEG    DIST = 14.1 KM
 EVENT   9  19580712.0330.00   0.04(1.05)  -0.023(0.90)   0.084(0.90)   0.00(1.00) AZIM =  106 DEG    DIST =  9.5 KM

The first line provides the calibration shift applied to the cluster, followed by the calibrated hypocentroid parameters. The following lines list the calibration shift required in each parameter (in the order: OT, lat, lon, depth), based on each calibration event, and each parameter is followed in parentheses by the weight given that datum in calculating the optimal shift. The weights are based on the uncertainty of that parameter in the calibration data and in the corresponding event cluster vector.

Cluster Statistics Section

This section tracks the cumulative squared error and number of data used for the cluster vectors through each iteration, and calculates the normalized sample variance shatc over all cluster vectors. In the early stages of a relocation shatc will usually be greater than 1 but as outlier readings are flagged and empirical reading errors are developed, it should finally be very close to 1.0. From ridgecrest3.1:

 cluster vector statistics   ITER      E**2/NSTA      SHATC
                               0       5928.2/ 7510    0.99
                               1       5649.7/ 7556    0.96
                               2       5650.0/ 7556    0.96
 Spread of event normalized sample variances:  0.161

The last line of this section is based on an analysis of the normalized sample variances for each event in the cluster, which are listed in the event section. These values are expected to be normally distributed around 1.0 with a spread determined by Bayesian considerations, as discussed in Jordan and Sverdrup (1981). The relevant code is in the module mlocinv.f90, in the section “Confidence ellipses for lat-long” beginning on line 402, which contains a lengthy comment on the approach used. As noted therein a conservative choice of k=3 is made for the Bayesian parameter, which leads to an expected spread of 0.4 for the normalized cluster sample variances. One could review the observed spreads of many clusters and perhaps decide to change the value of the Bayesian parameter (probably raise it), but this has not yet been done.

If the spread of event normalized sample variances were noticed to be significantly larger than expected, it means one (or probably more) of the individual cluster vectors have major problems, and investigation is certainly warranted.

Cluster Vector Changes Section

This section lists three columns for the cluster vector of each event, the initial vector, the final vector and (in the middle) the change vector. In the early stages of a relocation, the change vectors are often large but by the end they should be very close to zero, as the relocation is started from the previous location and converges immediately without any events moving around. During relocation if one or a few events are unstable they can be spotted quickly in the “CHANGE” column. If a preliminary or exploratory cluster contains some events that end up being rather far away from the area of interest, the “FINAL” column of the output is a convenient way to pick them out. Here is the section from the ridgecrest3.1 run:

                                       INITIAL                      CHANGE                       FINAL
 EVENT   1  19930520.2014.14    36.2 KM  AT  340 DEG          0.0 KM  AT    0 DEG         36.2 KM  AT  340 DEG
 EVENT   2  19950817.2239.57    12.4 KM  AT  269 DEG          0.0 KM  AT    0 DEG         12.4 KM  AT  270 DEG
 EVENT   3  19950830.1529.53     8.2 KM  AT  267 DEG          0.0 KM  AT    0 DEG          8.2 KM  AT  267 DEG
 EVENT   4  19950920.2327.35    10.0 KM  AT  249 DEG          0.0 KM  AT    0 DEG         10.0 KM  AT  249 DEG
 EVENT   5  19950925.0447.28     5.7 KM  AT  306 DEG          0.0 KM  AT    0 DEG          5.8 KM  AT  307 DEG
 EVENT   6  19951018.1242.04     8.5 KM  AT  225 DEG          0.0 KM  AT    0 DEG          8.5 KM  AT  225 DEG
 EVENT   7  19960107.1432.52    12.0 KM  AT  250 DEG          0.0 KM  AT    0 DEG         12.0 KM  AT  250 DEG
 EVENT   8  19960108.0857.10     8.1 KM  AT  258 DEG          0.0 KM  AT    0 DEG          8.1 KM  AT  258 DEG
 EVENT   9  19960108.1052.29     4.4 KM  AT  253 DEG          0.0 KM  AT    0 DEG          4.4 KM  AT  253 DEG
 EVENT  10  19960126.1306.02     7.9 KM  AT  263 DEG          0.0 KM  AT    0 DEG          7.9 KM  AT  263 DEG
 EVENT  11  19961127.2017.24    33.4 KM  AT  347 DEG          0.0 KM  AT    0 DEG         33.5 KM  AT  347 DEG
 EVENT  12  19961217.0403.22    35.5 KM  AT  348 DEG          0.0 KM  AT    0 DEG         35.6 KM  AT  348 DEG
 EVENT  13  20081125.0411.36    29.8 KM  AT   46 DEG          0.0 KM  AT    0 DEG         29.8 KM  AT   46 DEG
 EVENT  14  20081202.1123.43    32.2 KM  AT   47 DEG          0.0 KM  AT    0 DEG         32.2 KM  AT   47 DEG
 EVENT  15  20081202.1641.19    30.1 KM  AT   48 DEG          0.0 KM  AT    0 DEG         30.1 KM  AT   48 DEG
 EVENT  16  20081202.1653.09    30.4 KM  AT   48 DEG          0.0 KM  AT    0 DEG         30.4 KM  AT   48 DEG
 EVENT  17  20090131.2109.21    45.3 KM  AT  204 DEG          0.0 KM  AT    0 DEG         45.4 KM  AT  204 DEG
 EVENT  18  20090220.1219.13    33.0 KM  AT   47 DEG          0.0 KM  AT    0 DEG         32.9 KM  AT   47 DEG
 EVENT  19  20121202.1020.34    42.6 KM  AT  323 DEG          0.0 KM  AT    0 DEG         42.6 KM  AT  323 DEG
 EVENT  20  20131223.1339.26    60.0 KM  AT  311 DEG          0.0 KM  AT    0 DEG         60.0 KM  AT  311 DEG
 EVENT  21  20140304.2249.31    31.3 KM  AT   50 DEG          0.0 KM  AT    0 DEG         31.3 KM  AT   50 DEG
 EVENT  22  20140313.0211.04    57.9 KM  AT  310 DEG          0.0 KM  AT    0 DEG         57.9 KM  AT  310 DEG
 EVENT  23  20160809.0424.56    33.6 KM  AT  326 DEG          0.0 KM  AT    0 DEG         33.6 KM  AT  326 DEG
 EVENT  24  20170822.1951.58    59.5 KM  AT   76 DEG          0.0 KM  AT    0 DEG         59.5 KM  AT   76 DEG
 EVENT  25  20170919.1845.44    32.3 KM  AT  325 DEG          0.0 KM  AT    0 DEG         32.3 KM  AT  325 DEG
 EVENT  26  20190704.1702.55    11.1 KM  AT  145 DEG          0.0 KM  AT    0 DEG         11.1 KM  AT  145 DEG
 EVENT  27  20190704.1733.49    11.3 KM  AT  145 DEG          0.0 KM  AT    0 DEG         11.3 KM  AT  145 DEG
 EVENT  28  20190704.1735.01    15.9 KM  AT  177 DEG          0.0 KM  AT    0 DEG         15.9 KM  AT  178 DEG
 EVENT  29  20190704.1737.55     4.8 KM  AT  160 DEG          0.0 KM  AT    0 DEG          4.8 KM  AT  160 DEG
 EVENT  30  20190704.1740.18    10.6 KM  AT  151 DEG          0.0 KM  AT    0 DEG         10.6 KM  AT  151 DEG
 EVENT  31  20190704.1744.32    12.8 KM  AT  151 DEG          0.0 KM  AT    0 DEG         12.8 KM  AT  151 DEG
 EVENT  32  20190704.1806.16    15.1 KM  AT  162 DEG          0.0 KM  AT    0 DEG         15.1 KM  AT  162 DEG
 EVENT  33  20190704.1827.59     5.2 KM  AT  160 DEG          0.0 KM  AT    0 DEG          5.2 KM  AT  160 DEG
 EVENT  34  20190704.1828.43    13.7 KM  AT  180 DEG          0.0 KM  AT    0 DEG         13.7 KM  AT  180 DEG
 EVENT  35  20190704.1839.44    20.4 KM  AT  184 DEG          0.0 KM  AT    0 DEG         20.4 KM  AT  184 DEG
 EVENT  36  20190704.1847.06    15.0 KM  AT  146 DEG          0.0 KM  AT    0 DEG         15.0 KM  AT  146 DEG
 EVENT  37  20190704.1854.13    21.3 KM  AT  186 DEG          0.0 KM  AT    0 DEG         21.3 KM  AT  186 DEG
 EVENT  38  20190704.1856.06     7.9 KM  AT  172 DEG          0.0 KM  AT    0 DEG          7.9 KM  AT  172 DEG
 EVENT  39  20190704.1921.32    15.6 KM  AT  147 DEG          0.0 KM  AT    0 DEG         15.6 KM  AT  147 DEG
 EVENT  40  20190704.1956.00    14.8 KM  AT  162 DEG          0.0 KM  AT    0 DEG         14.8 KM  AT  162 DEG
 EVENT  41  20190704.2212.08     5.0 KM  AT  177 DEG          0.0 KM  AT    0 DEG          5.0 KM  AT  177 DEG
 EVENT  42  20190704.2334.00    15.0 KM  AT  164 DEG          0.0 KM  AT    0 DEG         15.0 KM  AT  164 DEG
 EVENT  43  20190705.0018.01     4.8 KM  AT  248 DEG          0.0 KM  AT    0 DEG          4.8 KM  AT  248 DEG
 EVENT  44  20190705.1107.53     3.2 KM  AT  193 DEG          0.0 KM  AT    0 DEG          3.2 KM  AT  193 DEG
 EVENT  45  20190706.0319.52     3.3 KM  AT  230 DEG          0.0 KM  AT    0 DEG          3.3 KM  AT  230 DEG
 EVENT  46  20190706.0346.26    14.7 KM  AT  143 DEG          0.0 KM  AT    0 DEG         14.7 KM  AT  143 DEG
 EVENT  47  20190706.0407.04    25.8 KM  AT  168 DEG          0.0 KM  AT    0 DEG         25.8 KM  AT  168 DEG
 EVENT  48  20190706.0413.07    20.9 KM  AT  199 DEG          0.0 KM  AT    0 DEG         20.9 KM  AT  199 DEG
 EVENT  49  20190706.0440.16    19.4 KM  AT  148 DEG          0.0 KM  AT    0 DEG         19.4 KM  AT  148 DEG
 EVENT  50  20190706.0832.57    18.8 KM  AT  156 DEG          0.0 KM  AT    0 DEG         18.8 KM  AT  156 DEG
 EVENT  51  20190706.0859.55    23.0 KM  AT  145 DEG          0.0 KM  AT    0 DEG         23.0 KM  AT  145 DEG
 EVENT  52  20190706.1636.04    24.8 KM  AT  166 DEG          0.0 KM  AT    0 DEG         24.8 KM  AT  166 DEG
 EVENT  53  20190706.2350.41     9.4 KM  AT  293 DEG          0.0 KM  AT    0 DEG          9.4 KM  AT  293 DEG
 EVENT  54  20190707.0538.15     2.7 KM  AT  185 DEG          0.0 KM  AT    0 DEG          2.7 KM  AT  185 DEG
 EVENT  55  20190707.1122.16     2.6 KM  AT  323 DEG          0.0 KM  AT    0 DEG          2.6 KM  AT  322 DEG
 EVENT  56  20190710.2009.51    14.4 KM  AT  162 DEG          0.0 KM  AT    0 DEG         14.4 KM  AT  162 DEG
 EVENT  57  20190711.2345.18    21.9 KM  AT  326 DEG          0.0 KM  AT    0 DEG         21.9 KM  AT  326 DEG
 EVENT  58  20190712.1311.37    16.7 KM  AT  184 DEG          0.0 KM  AT    0 DEG         16.7 KM  AT  184 DEG

Data Importance Distribution Section

The concept of data importance is discussed in Jordan and Sverdrup (1981). This section displays the cumulative data importance of all the readings in 30° azimuthal wedges, for the hypocentroid, for the cluster vectors of individual events and the cluster vectors in total. This is a useful way to investigate the azimuthal distribution of the data, which is a critical aspect of a reliable relocation. It is difficult to quickly comprehend the numbers in the main table, so a graphical summary is shown at the end of each event line. If the cumulative data importance in a wedge is less than 0.010 the symbol “0” is plotted. Otherwise a “-” is plotted. A more precise measure of open azimuth for each event is found in the HDF file.

In practice, events with an open azimuth up to about 220° are usually stable in mloc. In this graphical display 6 or fewer “zeros” in a row (including wrap-around) are usually not worrisome.

 DATA IMPORTANCE:               NNE    NE   ENE   ESE    SE   SSE   SSW    SW   WSW   WNW    NW   NNW
  HYPOCENTROID:               0.070 0.016 0.096 0.093 0.077 0.059 0.037 0.110 0.060 0.090 0.118 0.175
  EVENT   1  19930520.2014.14 0.054 0.167 0.019 0.001 0.083 0.139 0.000 0.210 0.126 0.113 0.056 0.032   ---0--0-----
  EVENT   2  19950817.2239.57 0.124 0.069 0.085 0.006 0.065 0.170 0.004 0.146 0.035 0.165 0.053 0.078   ---0--0-----
  EVENT   3  19950830.1529.53 0.056 0.093 0.069 0.010 0.049 0.170 0.025 0.044 0.187 0.190 0.047 0.058   ------------
  EVENT   4  19950920.2327.35 0.057 0.073 0.092 0.005 0.088 0.126 0.058 0.093 0.140 0.108 0.059 0.100   ---0--------
  EVENT   5  19950925.0447.28 0.074 0.046 0.098 0.011 0.064 0.113 0.109 0.077 0.072 0.132 0.119 0.085   ------------
  EVENT   6  19951018.1242.04 0.035 0.082 0.065 0.022 0.085 0.144 0.072 0.077 0.143 0.119 0.056 0.101   ------------
  EVENT   7  19960107.1432.52 0.070 0.103 0.068 0.011 0.042 0.149 0.005 0.146 0.035 0.226 0.004 0.139   ------0---0-
  EVENT   8  19960108.0857.10 0.041 0.099 0.007 0.052 0.016 0.183 0.028 0.198 0.059 0.114 0.077 0.126   --0---------
  EVENT   9  19960108.1052.29 0.022 0.074 0.042 0.002 0.089 0.149 0.046 0.105 0.090 0.193 0.033 0.155   ---0--------
  EVENT  10  19960126.1306.02 0.043 0.042 0.059 0.031 0.065 0.136 0.022 0.091 0.165 0.184 0.032 0.129   ------------
  EVENT  11  19961127.2017.24 0.057 0.076 0.091 0.009 0.075 0.123 0.059 0.103 0.177 0.012 0.144 0.074   ---0--------
  EVENT  12  19961217.0403.22 0.103 0.069 0.034 0.002 0.086 0.064 0.127 0.222 0.055 0.057 0.142 0.040   ---0--------
  EVENT  13  20081125.0411.36 0.022 0.096 0.006 0.111 0.143 0.080 0.119 0.080 0.084 0.006 0.207 0.046   --0------0--
  EVENT  14  20081202.1123.43 0.031 0.103 0.029 0.106 0.146 0.075 0.075 0.107 0.042 0.109 0.131 0.046   ------------
  EVENT  15  20081202.1641.19 0.023 0.088 0.005 0.119 0.162 0.080 0.121 0.092 0.042 0.000 0.232 0.036   --0------0--
  EVENT  16  20081202.1653.09 0.030 0.094 0.006 0.121 0.129 0.080 0.140 0.061 0.041 0.006 0.251 0.041   --0------0--
  EVENT  17  20090131.2109.21 0.060 0.079 0.063 0.147 0.091 0.065 0.081 0.019 0.084 0.143 0.009 0.160   ----------0-
  EVENT  18  20090220.1219.13 0.030 0.099 0.026 0.101 0.127 0.130 0.064 0.081 0.081 0.099 0.113 0.049   ------------
  EVENT  19  20121202.1020.34 0.031 0.057 0.071 0.160 0.095 0.114 0.119 0.114 0.034 0.001 0.031 0.173   ---------0--
  EVENT  20  20131223.1339.26 0.026 0.053 0.097 0.134 0.140 0.085 0.098 0.093 0.059 0.051 0.035 0.130   ------------
  EVENT  21  20140304.2249.31 0.024 0.101 0.016 0.090 0.131 0.094 0.052 0.125 0.109 0.063 0.163 0.031   ------------
  EVENT  22  20140313.0211.04 0.013 0.051 0.019 0.106 0.179 0.161 0.129 0.095 0.063 0.024 0.003 0.156   ----------0-
  EVENT  23  20160809.0424.56 0.045 0.049 0.106 0.116 0.117 0.093 0.035 0.169 0.039 0.019 0.160 0.050   ------------
  EVENT  24  20170822.1951.58 0.151 0.075 0.012 0.114 0.044 0.143 0.044 0.093 0.071 0.149 0.009 0.097   ----------0-
  EVENT  25  20170919.1845.44 0.031 0.087 0.076 0.096 0.122 0.086 0.111 0.146 0.037 0.020 0.138 0.049   ------------
  EVENT  26  20190704.1702.55 0.122 0.079 0.111 0.061 0.073 0.076 0.016 0.098 0.080 0.105 0.141 0.038   ------------
  EVENT  27  20190704.1733.49 0.091 0.116 0.067 0.038 0.149 0.070 0.015 0.070 0.123 0.040 0.141 0.080   ------------
  EVENT  28  20190704.1735.01 0.094 0.023 0.024 0.076 0.112 0.011 0.030 0.167 0.114 0.083 0.111 0.154   ------------
  EVENT  29  20190704.1737.55 0.118 0.000 0.032 0.000 0.198 0.016 0.170 0.031 0.138 0.000 0.205 0.090   -0-0-----0--
  EVENT  30  20190704.1740.18 0.022 0.085 0.019 0.023 0.155 0.040 0.003 0.164 0.110 0.072 0.166 0.142   ------0-----
  EVENT  31  20190704.1744.32 0.037 0.121 0.115 0.021 0.119 0.075 0.009 0.112 0.136 0.061 0.050 0.145   ------0-----
  EVENT  32  20190704.1806.16 0.035 0.155 0.028 0.029 0.140 0.067 0.005 0.188 0.053 0.061 0.084 0.154   ------0-----
  EVENT  33  20190704.1827.59 0.119 0.021 0.038 0.043 0.172 0.017 0.106 0.028 0.125 0.091 0.145 0.093   ------------
  EVENT  34  20190704.1828.43 0.091 0.033 0.023 0.072 0.151 0.016 0.141 0.024 0.107 0.063 0.085 0.194   ------------
  EVENT  35  20190704.1839.44 0.135 0.062 0.022 0.075 0.075 0.098 0.030 0.184 0.068 0.056 0.095 0.100   ------------
  EVENT  36  20190704.1847.06 0.072 0.095 0.034 0.065 0.112 0.047 0.003 0.181 0.095 0.109 0.082 0.105   ------0-----
  EVENT  37  20190704.1854.13 0.097 0.140 0.018 0.122 0.052 0.048 0.003 0.170 0.091 0.078 0.078 0.104   ------0-----
  EVENT  38  20190704.1856.06 0.027 0.044 0.105 0.057 0.169 0.023 0.156 0.028 0.163 0.020 0.067 0.141   ------------
  EVENT  39  20190704.1921.32 0.040 0.189 0.028 0.041 0.110 0.073 0.036 0.122 0.058 0.104 0.089 0.112   ------------
  EVENT  40  20190704.1956.00 0.054 0.180 0.043 0.054 0.062 0.087 0.029 0.151 0.068 0.072 0.129 0.072   ------------
  EVENT  41  20190704.2212.08 0.035 0.123 0.053 0.065 0.124 0.073 0.055 0.035 0.126 0.068 0.184 0.059   ------------
  EVENT  42  20190704.2334.00 0.046 0.116 0.035 0.063 0.137 0.057 0.025 0.121 0.146 0.054 0.132 0.070   ------------
  EVENT  43  20190705.0018.01 0.068 0.042 0.141 0.059 0.119 0.051 0.116 0.053 0.078 0.057 0.048 0.167   ------------
  EVENT  44  20190705.1107.53 0.098 0.074 0.059 0.064 0.077 0.096 0.102 0.073 0.107 0.048 0.098 0.103   ------------
  EVENT  45  20190706.0319.52 0.105 0.086 0.057 0.056 0.137 0.086 0.128 0.062 0.048 0.061 0.136 0.038   ------------
  EVENT  46  20190706.0346.26 0.056 0.201 0.009 0.012 0.087 0.102 0.059 0.124 0.129 0.058 0.098 0.066   --0---------
  EVENT  47  20190706.0407.04 0.084 0.127 0.002 0.140 0.066 0.021 0.027 0.165 0.093 0.121 0.075 0.079   --0---------
  EVENT  48  20190706.0413.07 0.089 0.103 0.246 0.038 0.036 0.022 0.000 0.203 0.004 0.098 0.015 0.147   ------0-0---
  EVENT  49  20190706.0440.16 0.118 0.095 0.000 0.092 0.201 0.118 0.020 0.119 0.004 0.184 0.000 0.048   --0-----0-0-
  EVENT  50  20190706.0832.57 0.059 0.097 0.074 0.058 0.075 0.059 0.034 0.197 0.034 0.053 0.159 0.100   ------------
  EVENT  51  20190706.0859.55 0.104 0.040 0.004 0.089 0.121 0.082 0.091 0.128 0.104 0.043 0.097 0.098   --0---------
  EVENT  52  20190706.1636.04 0.138 0.257 0.039 0.050 0.093 0.116 0.099 0.013 0.048 0.018 0.000 0.128   ----------0-
  EVENT  53  20190706.2350.41 0.053 0.084 0.029 0.111 0.065 0.085 0.144 0.074 0.052 0.149 0.066 0.089   ------------
  EVENT  54  20190707.0538.15 0.118 0.017 0.118 0.098 0.067 0.094 0.106 0.013 0.069 0.096 0.154 0.052   ------------
  EVENT  55  20190707.1122.16 0.049 0.064 0.092 0.066 0.090 0.086 0.113 0.105 0.077 0.056 0.099 0.102   ------------
  EVENT  56  20190710.2009.51 0.063 0.108 0.082 0.040 0.122 0.085 0.034 0.116 0.075 0.056 0.137 0.082   ------------
  EVENT  57  20190711.2345.18 0.070 0.114 0.048 0.108 0.071 0.134 0.103 0.052 0.039 0.141 0.068 0.051   ------------
  EVENT  58  20190712.1311.37 0.074 0.067 0.092 0.060 0.065 0.090 0.056 0.119 0.055 0.065 0.133 0.125   ------------
  CLUSTER VECTORS:            0.066 0.089 0.054 0.065 0.105 0.089 0.066 0.108 0.084 0.081 0.098 0.095

Event Section

The final section of a summary file lists details of the relocation for all events. The first event from the ridgecrest3.1 run is listed:

 CLUSTER EVENT   1 19930520.2014.14                        ridgecrest3/19930520.2014.14.mnf
 MAG    4.2
 Cluster vector location parameters: (lat, lon,      , origin time)
            DATE         TIME        LATITUDE     LONGITUDE       DEPTH         EC**2/NSTA    EH**2/NSTA  PRMAX  DELT PRES FLAG
 INPUT    5/20/1993   20:14:14.01      36.057      -117.632         0.8
 START    5/20/1993   20:14:14.08      36.093      -117.704        13.0

 ITER 0                      0.01 S     0.16 KM      -0.20 KM       0.00 KM      51.3/  65      0.3/   6    4.0    94   10   20
 ITER 1                     -0.01 S    -0.14 KM       0.18 KM       0.00 KM      50.6/  67      0.4/   6    4.0    94    8   20
 ITER 2                      0.00 S     0.01 KM      -0.01 KM       0.00 KM      50.6/  67      0.3/   6    4.0    94    8   20

  CUMULATIVE                 0.00 S     0.03 KM      -0.02 KM       0.00 KM    AZIM =    0 DEG    DIST =  0.0 KM
 +HYPOCENTROID               0.00 S     0.01 KM       0.01 KM       0.00 KM
  TOTAL                      0.00 S     0.03 KM      -0.02 KM       0.00 KM    AZIM =    0 DEG    DIST =  0.0 KM

 SOLUTION  5/20/1993  20:14:14.08      36.094      -117.704        13.0
 STANDARD ERRORS             0.05 S     0.004 DEG     0.005 DEG     0.00 KM    ELLIPSE:  55.0 DEG   0.8 AND    0.9 KM

 SOLUTION-INPUT              0.07 S     0.037 DEG    -0.072 DEG    12.20 KM    AZIM =  302 DEG    DIST =  7.7 KM

 Normalized sample variance for cluster vector:  0.789 (  -1.32)

The first line gives the event number, the event “name” and the pathname to the input (~.mnf) file. Cluster vector location parameters (i.e., free parameters) are usually the same as for the hypocentroid. The starting location for most runs (except the first few, until the command rhdf begins to be used) will normally be different from the hypocenter in the .mnf file.

At each iteration the squared error and number of data are listed both for the event’s cluster vector and its contribution (if any) to the hypocentroid. The cumulative changes in cluster vector parameters are listed and then the changes to the hypocentroid are added to obtain the final location. Standard errors are those of the cluster vector only. The difference between final location and the input location (.mnf file) are calculated.

Finally, the event normalized sample variance is calculated and the “residual” (relative to an expected value of 1.0 and normalized by the spread of event normalized sample variances), discussed in the Cluster Statistics Section, is shown in parentheses. In this case, the spread is 0.161, so:

(0.789-1.0)/0.161 = -1.32

Interpretation of these numbers is not straight-forward, because the expected value of 1.0 is not always representative. In the ridgecrest3.1 relocation the mean of all event normalized sample variances is ~0.79, so this event is not “better than average”, but rather right on the mean for the cluster. Overall, this cluster displays less error than expected between observed and predicted arrival times, even after empirical reading errors are accounted for. One possible cause is the minimum allowed reading error. If many readings are being given artificially large reading errors, the observed discrepancy may be explained. Some clusters deviate in the other direction. The source(s) of these discrepancies have not been investigated. In any case values of the normalized event sample variance greater than ~2 are worthy of some investigation. The event normalized sample variance for each event is also listed in the HDF file. It is usually more convenient to review these values there.

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