Strong-Motion Data

Strong-motion accelerographs are located in major centres of population, near significant faults, or in different types of building structures. They are capable of measuring very strong shaking associated with damaging earthquakes.

Etna accelerograph.

New Zealand's current strong-motion network is largely instrumented with the Kinemetrics Etna accelerograph. Data files from these instruments are available from ftp.geonet.org.nz/strong/raw, and software for manipulating and decoding them is available from the manufacturer. The station codes may be viewed on the network maps, and the site locations and operational dates may be found in DELTA.

The data holdings are updated every hour with recent files received from our network. Please note that they may include data from non-seismic sources, such as bumps and electrical interference.

The entire New Zealand collection of processed strong-motion data is available from ftp.geonet.org.nz/strong/processed/Proc. It includes accelerograms and response spectra from both current and obsolete recorders. Data files are in ASCII format, and relevant documentation for decoding the files and descriptions of site conditions may be found in ftp.geonet.org.nz/strong/processed/Docs.

Worldwide strong-motion data resources are centralised at the COSMOS Virtual Data Center. This gives access to a database of strong ground motion data parameters, and links to the data centres and web sites of the contributing agencies.