TauP DistazΒΆ

TauP Distaz calculates great circle path distances between lat/lon points.

For example:

taup distaz --sta 31 -80 --evt -11 21

gives you spherical distance in degrees, azimuth and back azimuth between latitude longitude points -11/21 and 31/-80.

Degrees      Km     Azimuth  BackAz    Source    Receiver      Description   (Spherical)  
---------------------------------------------------------------------------------------------
  105.00  11675.5   -60.59     93.98 -11.00/21.00 31.00/-80.00      -11.00/21.00 to 31.00/-80.00

If you have a QuakeML file for earthquakes or a StationXML file for stations and channels, you can use those to calculate the distances directly. It is often useful to use either --geodist geodetic or --geodist geocentric when using latitudes and longitudes so that the distance calculation is more accurate. For example:

taup distaz --quakeml my_midatlantic.qml --staxml my_stations.staml --geodist geodetic

gives you distances from these earthquakes to those stations.

Degrees      Km     Azimuth  BackAz    Source    Receiver      Description   (Geodetic 298.257223563)  
---------------------------------------------------------------------------------------------
   30.56   3397.8    15.63   -121.77 2024-08-30T09:32:19 5.6 mww 52.61/-33.27 10.00 km IU_KBS 78.92/11.94      2024-08-30T09:32:19 5.6 mww 52.61/-33.27 10.00 km to IU_KBS 78.92/11.94
   38.51   4281.9   -98.92     46.62 2024-08-30T09:32:19 5.6 mww 52.61/-33.27 10.00 km CO_JSC 34.28/-81.26      2024-08-30T09:32:19 5.6 mww 52.61/-33.27 10.00 km to CO_JSC 34.28/-81.26
   57.74   6420.6   -77.66     44.65 2024-08-30T09:32:19 5.6 mww 52.61/-33.27 10.00 km IU_TUC 32.31/-110.78      2024-08-30T09:32:19 5.6 mww 52.61/-33.27 10.00 km to IU_TUC 32.31/-110.78
  157.98  17566.2   -69.92     49.45 2024-08-30T09:32:19 5.6 mww 52.61/-33.27 10.00 km IU_SNZO_00_H_H_Z -41.31/174.70 91.00 m      2024-08-30T09:32:19 5.6 mww 52.61/-33.27 10.00 km to IU_SNZO_00_H_H_Z -41.31/174.70 91.00 m
  157.98  17566.2   -69.92     49.45 2024-08-30T09:32:19 5.6 mww 52.61/-33.27 10.00 km IU_SNZO_10_H_H_Z -41.31/174.70 0.00 m      2024-08-30T09:32:19 5.6 mww 52.61/-33.27 10.00 km to IU_SNZO_10_H_H_Z -41.31/174.70 0.00 m

It can also calculate from event, distance and azimuth.

taup distaz --sta -11 21 --baz -135 --deg 30 --geodist geodetic
Degrees      Km     Azimuth  BackAz    Source    Receiver      Description   (Geodetic 298.257223563)  
---------------------------------------------------------------------------------------------
   30.00   3335.8    53.93   -135.00 -30.90/-3.28 -11.00/21.00      baz  -135.00 from -11.00/21.00

Or from station, distance and back azimuth.

taup distaz --evt -11 21 --az 35 --km 3000 --geodist geodetic
Degrees      Km     Azimuth  BackAz    Source    Receiver      Description   (Geodetic 298.257223563)  
---------------------------------------------------------------------------------------------
   26.98   3000.0    35.00   -144.95 -11.00/21.00 11.35/36.37      -11.00/21.00 to az 35.00

The usage is:

Usage: taup distaz [--debug] [--geodetic] [--help] [--verbose] [--az=<azimuth>]
                   [--baz=<backAzimuth>] [--equitorialradius=m]
                   [--invflattening=f] [-o=<outFile>] [--planet=<planet>]
                   [--prop=<toolPropsFilename>] [--qml=<quakemlFilename>]
                   [--staxml=<stationxmlFilename>] [--eid=evt[,evt...]]...
                   [-h=depth[,depth...]]... [--sid=sta[,sta...]]...
                   [--stadepth=depth[,depth...]]... [--evt=lat lon]...
                   [--sta=lat lon]... [--geodist=<geoDistTypes>...]... [--html
                   | --json | --text] [[--deg=d[,d...]]... [--km=km[,km...]]...
                   [--degreerange=[step][min max][min max step]]...
                   [--kilometerrange=[step][min max][min max step]]...]...
                   [--mod=<modelName> | [--radius=<radiusOfEarth>]]
Calc distance, az and baz for event lat,lon and station lat,lon pairs.

Options:

      --az=<azimuth>         azimuth in degrees, source to receiver
      --baz=<backAzimuth>    backazimuth in degrees, receiver to source
      --debug                enable debugging output
      --eid=evt[,evt...]     event id, like us7000pn9s, for lookup via USGS
                               fdsn event web service. Creates a distance if
                               station is also given.
      --equitorialradius=m   Equitorial radius in meters for distance
                               calculations when geodetic or geocentric,
                               defaults to WGS84 ~ 6378137 meters.
      --evt, --event=lat lon event latitude and longitude.  Creates a distance
                               if station is also given.
      --geodetic             use geodetic latitude for distance calculations,
                               which implies an ellipticity. Default is
                               spherical. Note this only affects calculation of
                               distance from lat/lon pairs, all travel time
                               calculations are done in a purely spherical
                               model.
      --geodist=<geoDistTypes>...
                             Type of distance calculation to use for lat,lon
                               distance calculation, one of spherical,
                               geocentric, geodetic. Default is spherical. Note
                               this only affects calculation of distance from
                               lat/lon pairs, all travel time calculations are
                               done in a purely spherical model.
  -h, --evdepth, --sourcedepth=depth[,depth...]
                             source depth in km
      --help                 display this help message
      --invflattening, --geodeticflattening=f
                             Inverse Elliptical flattening for distance
                               calculations when geocentric or geodetic,
                               defaults to WGS84 ~ 298.257. The distance
                               calculation uses 1/x.
      --mod, --model=<modelName>
                             use velocity model "modelName" for radius, used
                               when distance given in km.
  -o, --output=<outFile>     output to file, default is stdout.
      --planet=<planet>      Geodesic for planets, for distance calculations
                               when --geodetic, one of: EARTH, MOON, MARS,
                               VENUS, MERCURY, CERES, JUPITER, SATURN, URANUS,
                               NEPTUNE.
      --prop=<toolPropsFilename>
                             load defaults from properties file
      --qml, --quakeml=<quakemlFilename>
                             QuakeML file to load for earthquake origins to use
      --radius=<radiusOfEarth>
                             radius of earth in km, used when distance given in
                               km
      --sid=sta[,sta...]     station id, like CO.HAW or FDSN:CO_HAW, for lookup
                               via fedcat web service. Creates a distance if
                               event is also given.
      --sta, --station=lat lon
                             station latitude and longitude. Creates a distance
                               if event is also given.
      --stadepth, --receiverdepth=depth[,depth...]
                             the receiver depth in km for stations not at the
                               surface
      --staxml=<stationxmlFilename>
                             StationXML file to extract station latitudes and
                               longitudes from
      --verbose              enable verbose output
Output Type:
      --html                 outputs as HTML
      --json                 outputs as JSON
      --text                 outputs as Text
Optional distance is given by:
      --deg, --degree=d[,d...]
                             distance in degrees
      --degreerange=[step][min max][min max step]
                             regular distance range in degrees, one of step;
                               min max or min max step. Default min is 0, max
                               is 180 and step is 10.
      --kilometerrange=[step][min max][min max step]
                             regular distance range in kilometers, one of step;
                               min max or min max step. Default min is 0, max
                               is 1000 and step is 100.
      --km, --kilometer=km[,km...]
                             distance in kilometers along surface.