DPC OB2 Project - Class version 1.0 Catalog Web Service

Help Message:
You can use the FOLLOWING query as a an example starting point and modify it according to the rules listed below:

Meaning of input parameters

eventid: it is the CLASS unique id of the event (corresponding to the set of readings) to which the presented location pertains. From 2009 on it corresponds to eventidiv
eventidiv: it is the unique id of the ingv event on the ONT website to which the presented CLASS location corresponds. From 2009 on it corresponds to the eventid
startime: time to begin search
endtime: time to stop search
minlat: minimum latitude
maxlat: maximum latitude
minlon: minimum longitude
maxlon: maximum longitude
mindepth: minimum depth
maxdepth: maximum depth
minmag: minimum magnitude
maxmag: maximum magnitude

default is 'exclude'
minfaps: minimum number of p+s readings
maxrms: maximum value of RMS for location
maxgap: maximum value of azimuthal gap for location
maxher: maximum value of horizontal error (km) for location
maxver: maximum value of vertical error (km) for location
minclass: from A (best) to D (worse) class of location based on combined analysis of formal errors
orderby: [orderby=(time | time-asc | magnitude | magnitude-asc )] default is time descendent
format: [text|html] default is text

Only starttime + endtime or eventid are mandatory inputs
The order of the parameters is not relevant

Output description

The probabilistic hypocenter location of ~400,000 earthquakes 1981-2018 is here released, with location quality parameters, a quality class attributed (A-->E), a set of available magnitudes, and (when possible) the ID of the INGV monitoring system to retrieve additional information as for example resentment, focal mechanism/TDMT, shakemaps.
Please refer to the MenĂ¹ at the top of this site to download the .csv.gzip or the .kml.gzip or to use the dedicated webservice to download the product.
Here below the webservice output format are detailed.

Unique identification numbers

  • id_class is the unique number of class_events; from 1981 to 2008 it corresponds to the CSI 2.0 id while from 2009 to 2018 it is identical to id_ingv
  • id_ingv is the unique number of seismic events given by the INGV monitoring system
  • id: in the last column an internal database number is reported

Hypocenter parameters

  • origintime (of the earthquakes), probabilistic
  • latitude, longitude, depth (positive downward)


  • magnitude_class is the preferred among the available ones (possibly an ML)
  • magnitude_class_type is the source/type of the selected value
  • magnitude_ingv_loc is the estimate that INGV attributed to its own location (1981-2004 tipically Md and a few ML, 2005 on tipically to almost only ML)
  • magnitude_ingv_loc_type is the source/type of the selected value
  • magnitude_ingv_pref is the best available estimation that INGV attributed to the earthquake up to the last check (it can be the magnitude_ingv_loc itself or the Mw)
  • magnitude_ingv_pref_type is the source/type of the selected value

Quality parameters

  • rms: root mean square error from P and S arrival time residuals (s)
  • errh: hypocentral error on horizontal coordinates computed from the 68% ellipsoid error (km)
  • errv (errz): hypocentral error on vertical coordinates computed from the 68% ellipsoid error (km)
  • nphs: number of arrival time picks used in the hypocenter location inversion
  • gap: maximum azimuthal angle between two successive stations around the source epicenter (degrees)
  • mindist (sdist): minimum station epicentral distance (km)
  • pdfray (Rpdf): radius of a sphere having volume equivalent to the PDF volume (km)
  • locd: distance between the probabilistic hypocenter and the expected linear location hypocenter (km)
  • qmd_cha: quality class expressed as text A (top) to D (worst) and E (depth not for any use)
  • qmd_num: quality class expressed as continuous floating numbers from 1 (top) to 0 worst (excluding E which is out of the range)