Scenario Hazard Analysis Outputs

By default, the scenario hazard calculator computes and stores Ground Motion Fields for each GMPE specified in the job configuration file. The Ground Motion Fields will be computed at each of the sites and for each of the intensity measure types specified in the job configuration file.

Exporting the outputs from the Ground Motion Fields in the csv format results in two csv files illustrated in the example files in the following tables. The sites csv file provides the association between the site ids in the Ground Motion Fields csv file with their latitude and longitude coordinates.

Example of a ground motion fields csv output file for a scenario

rlzi	sid	eid	gmv_PGA	gmv_SA(0.3)	gmv_SA(1.0)
0	0	0	0.062	0.119	0.157
0	1	0	0.086	1.533	0.260
0	2	0	0.223	1.647	0.232
…	…	…	…	…	…
1	4	99	2.467	0.750	1.918
1	5	99	0.601	0.828	2.272
1	6	99	0.514	0.340	1.202

In this example, the gmfs have been computed using two different GMPEs (and without conditioning the ground shaking to observations), so the realization indices (’rlzi’) in the first column of the example gmfs file are either 0 or 1. The gmfs file lists the ground motion values for 100 simulations of the scenario, so the event indices (’eid’) in the third column go from 0–99. There are seven sites with indices 0–6 (’sid’) which are repeated in the second column for each of the 100 simulations of the event and for each of the two GMPEs. Finally, the subsequent columns list the ground motion values for each of the intensity measure types specified in the job configuration file.

Example of a sites csv output file for a scenario

site_id	lon	lat
0	-122.57000	38.11300
1	-122.11400	38.11300
2	-122.00000	37.91000
3	-122.00000	38.00000
4	-122.00000	38.11300
5	-122.00000	38.22500
6	-121.88600	38.11300

For scenario hazard calculations that consider the conditioning of the ground shaking to siesmic station or macroseismic observations, the nominal event bias, one bias value for each IMT, and for every GSIM used in the calculation is displayed and stored in the calculation log. The calculation log can be obtained using oq engine --show-log CALC_ID in the terminal.