Southern California Earthquake Data Center

SCEDC Availability Web Service

The SCEDC availability web service returns time span information of what timeseries are available at the SCEDC archive. It implements the /extent and /query service methods.

Extent produces lists of available time extents (earliest to latest) for selected channels (network, station, channel,location) and time ranges. Extents can be queried for both continuous and triggered waveform data.
Query produces lists of continuous time spans for selected channels (network, station, channel, location) and time ranges. Query is available only for continuous waveform data.

Availability information is refreshed daily. At this stage, following data are availabile for
  • triggered records from Jan 1977 - present
  • continuous records from Oct 1999 - present


Note: Query end point updates are made on a daily basis but they are made at a delay to allow gaps in the archive to be filled. The most recent records are from 179 days ago.

Output formats supported are text, GeoCSV, JSON and request(query endpoint only). Please see help for details.

Please see Help for available query parameters.

Note: At this stage, triggered records from Jan 1977 - present and continuous records from Oct 1999 - present are available for queries.

Sample queries

Continuous waveforms

Extent information for all channels for network CI, station AGO

Extent information for all channels for network CI and station WBS for continuous waveforms in geocsv format

Extent information for all channels for network CI and station RPV for continuous waveforms in json format

Triggered waveforms

Extent information for network CI, station PASC, channel HHE for a given time interval

URL Builder

Input form parameters and notice the URL field at the bottom change dynamically. Click on the URL to run your query.
Note: At this stage, only continuous data for seismic channels (*H*, *N* and *L*) from are available for queries.
  1. SEED 2 character network code i.e. CI,AZ...
  2. SEED 5 character station code i.e. PASC,24400...
  3. SEED 2 character location code i.e. --,10...
  4. SEED 3 character channel code i.e. HHN,HNN,BH*...
  5. in UTC, format is yyyy-mm-ddThh:mm:ss[.ssssss]
  6. in UTC, format is yyyy-mm-ddThh:mm:ss[.ssssss]
URL: /fdsnws/station/1/query?
The URL used for extent and query endpoints and the available query parameters are described below.

  • /fdsnws/station/1/extent?[query-parameters]
  • /fdsnws/station/1/query?[query-parameters]

where query-parameters:

Empty/No parameters Will return availability of all channels at SCEDC.
net="network" Optional Specify SEED network code, example net=CI.
sta="station" Optional Specify SEED station code, example sta=BAK.
loc="location" Optional Specify SEED location code mask, example: loc=00. substitute dash characters for white space, example: loc=--.
cha="channel" Optional Specify SEED channel code mask, example: cha=BHE.
start=YYYY-MM-DDThh:mm:ss Optional Specify channels operating after this date.
end=YYYY-MM-DDThh:mm:ss Optional Specify channels operating before this date.
asset="asset" Optional Specify the asset type i.e. continuous or triggered. Default is continuous.
format=text | geocsv | json Optional Specify output format. Default is text.
text output format contains one time span per line with fields separated by spaces.
geocsv output format is a text format designed to contain enhanced metadata. It's specification can be found here.
json output format is defined using the JSON schema and can be found here.
request output format contains one time span per line in the FDSN web service POST-style request format. Valid for query endpoint only.
nodata=204|404 Optional Specify which HTML status code is returned when no data is found (Default is 204).

POST Usage:

/extent and /query can be accessed via HTTP POST. All parameters available in GET are also allowed in POST.
When using a data file for sending requests, the general form of a POST request is one or more global parameter=value lines, followed by any number of sncl i.e net sta loc cha values and optionally, time window selection lines. The order of parameters in the sncl lines is important and must be net sta loc chan [start end]. Sncl line(s) are required.

Generic form of a post data file
net sta loc cha [starttime endtime]
net sta loc cha [starttime2 endtime2]

The following table shows which parameters can be global for POST requests when submitting parameters via a data file.

global: parameter can be specified only once per POST data file in the form of parameter=value pair.
non-global: parameter must be specified in line like so net sta loc cha [start end]
any: parameter can be specified globally or in line


Alternatively, request parameters can also be submitted as a string, consisting of parameter=value pairs joined together by ampersand. The general format in such a case is

Example data files for POST request
CI PASC 00 HHE 2016-12-15T00:00:00 2016-12-16T00:00:00
CI AGO -- HN* 2016-12-15T00:00:00 2016-12-16T00:00:00

Start and end times can be specified globally, or individually with each channel or as a mix of global and individual time ranges.
endtime= 2017-01-31T23:59:59
CI PASC 00 HHE 2016-12-15T00:00:00 2016-12-16T00:00:00
CI ABL -- H*

Using curl or wget for POST requests with extent and query endpoints

curl and wget Unix utilities can be used to submit POST requests and the save the results in a text file.

  • wget --post-file=availability.req -O extent_out.txt
  • wget --post-data="net=CI&sta=AGO&cha=HNE&loc=--&start=2015-01-01T00:00:00&end=2016-01-01T00:00:00" -O extent_out.txt
  • wget --post-file=availability.req -O query_out.txt
  • wget --post-data="net=CI&sta=AGO&cha=HNE&loc=--&start=2015-01-01T00:00:00&end=2016-01-01T00:00:00" -O query_out.txt
  • curl --data-binary @availability.req -o extent_out.txt
  • curl --data "net=CI&sta=AGO&cha=HNE&loc=--&start=2015-01-01T00:00:00&end=2016-01-01T00:00:00" -o extent_out.txt
  • curl --data-binary @availability.req -o query_out.txt
  • curl --data "net=CI&sta=AGO&cha=HNE&loc=--&start=2015-01-01T00:00:00&end=2016-01-01T00:00:00" -o query_out.txt

Timespans for /extent and /query endpoints

  • /extent
  • The timespan displayed for a channel is the earliest and latest miniseed data points that fall within the specified start and end times. This includes any gaps that might be present. If no start and end times are specified, all available data is retrieved.
  • /query
  • For a channel, the query endpoint displays lists of continuous data, one continuous data segment per row. Hence, a channel may display several rows of availability depending on how gappy the data was for the queried time period.

Please use the citation: 
SCEDC (2013): Southern California Earthquake Data Center. Caltech. Dataset. doi:10.7909/C3WD3xH1
to cite data downloaded from the SCEDC.

Version: SCEDC Waveform Availability Service v1.0.0

Division of Geological and Planetary Sciences | California Institute of Technology