The IRIS DMC archives waveform (time-series) data from stations around the world. The following information highlights passive and active source data available through the DMC.
Waveform Data Formats
SEED (Standard for the Exchange of Earthquake Data) format
SEED is an international standard format for the exchange of digital seismological data. SEED was designed for use by the earthquake research community, primarily for the exchange between institutions of unprocessed earth motion data. It is a format for digital data measured at one point in space and at equal intervals of time.
SEED helps seismologists who record, share, and use seismological data. By providing a standard, SEED makes transmitting, receiving, and processing earthquake data easier and more accurate. Before the introduction of SEED, ease and accuracy had been goals, but not really attained.
- More on SEED.
- Read the SEED Manual
- The miniSEED format is described here.
- The dataless SEED format for metadata is described here.
Simple ASCII format
Simple ASCII is a text column representation timeseries data that IRIS DMC now provides. This representation makes it very simple to import into other utilities such as spreadsheets and mathematical analysis programs. More information on the Simple ASCII format »
SAC (Seismic Analysis Code) format
The SAC format comes in fixed binary and ASCII forms and is read by the SAC analysis utility: A general purpose interactive program designed for the study of sequential signals, especially time series data. More information on SAC »
The IRIS DMC distributes several pre-assembled data sets. Most of these data sets are from temporary deployments and in formats other than SEED. An assembled set is accompanied by a data report. We have assembled data from various sources including IRIS PASSCAL (mostly active source), the USGS, and others.