Kashima's Office

Supported data file

ViewWave can read various strong motion data files. ViewWave can treat strong motion data having the unit of cm/s2. So the unit of data is converted to cm/s2 when those are read.

BRI strong motion data files

Building Research Institute (BRI), Japan is providing strong motion data obtained that strong motion network. The data file has a file extension (ac) and consists multi-channel data recorded at a station. Please refer to;

NIED K-NET and KiK-net files

The National Research Institute for Earth Science and Disaster Prevention (NIED) is operating two large strong motion networks in Japan. The networks, which are called K-NET and KiK-net, provide strong motion data at the website.

A station of K-NET has a strong motion instrument on the ground and the instrument has a three-component acceleration sensor. A strong motion record consists of three files with file extensions, “EW”, “NS” and “UD.”

A KiK-net station has two acceleration sensors on the ground and in the borehole. The borehole sensor is usually placed on the seismic bedrock. Each sensor measures three-component accelerations. A strong motion record consists of six files with file extensions, “EW1,” “NS1,” ”UD1,” “EW2,” “NS2” AND “UD2.”

In case of both K-NET and KiK-net, ViewWave tries to read all files if one of data files is specified. Please refer to;

JMA data files

The Japan Meteorological Agency (JMA) deploys seismic intensity meters throughout Japan. The seismic intensity meter is an equipment to measure the JMA seismic intensity scale and works as a strong motion instrument as well. The strong motion records of the JMA seismic intensity meters are annually published from the Japan Meteorological Business Support Center (JMBSC). The publication, usually by CD or DVD, may include some strong motion data obtained in the seismic information networks of the local governments. There are two types of data files, i.e. a Hexa-ASCII converted file and a CSV file. A Hexa-ASCII file doesn’t have a fixed file extension, because that portion is occupied by the station code. ViewWave can read those data files.

  • JMA 95 Hexa-ASCII files (YMDDhhmm.*)
  • JMA CSV files (*.csv)

There are several types of seismic intensity meters and there are differences of sensitivity among those. Unfortunately, there is no way to know the intensity meter type from the data file. So ViewWave adjusts the amplitudes based on comparison of the peak values of the data and on the file header.

For more information, please refer to;

Binary files

Some strong motion instruments or dedicated software make binary files having peculiar formats. ViewWave can read some of such files directly. Currently, ViewWave supports the following binary files;

  • Mitutoyo (and Akashi) SMAC-MD/MDU files (*.md)
  • Tokyo Sokushin win32 binary files (*.t3w)
  • Tokyo Sokushin binary files (*.dbl)
  • Kinemetrics Altus K2/Etna event files (*.evt)

Mitutoyo, which merged Akashi, SMAC-MD/MDU instruments make a data file having a file extension “SMC” and some utility software puts “DAT” as a file extension. I usually replace the file extensions with “md” to avoid confusion. ViewWave checks file contents if those file extensions are found, therefore you don’t need to rename your data files.

ViewWave may read Kinemetrics “EVT” files, probably only made by K2 and Etna. Unfortunately, I never have an opportunity to try other instruments.

Major database files in United States

The United States of America leads the world in the field of strong motion instrumentation. There are several databases accessible on the Internet. ViewWave supports three major file formats as follows.

  • USGS (NSMP) files (*.smc)
  • CGS (CSMIP) files (*.raw; *.v2)
  • COSMOS files (*.v1c; *.v2c)

Further information on those data files is available at the following website;

PEER database files

Another often referred database in the United States will be the PEER Ground Motion Database at the University of California, Berkeley.ViewWave can read those acceleration files which have the file extension “AT2.”

New Zealand GeoNet files

GeoNet in New Zealand is operating the strong motion network covering the country. ViewWave can read those files having file extensions “V1A” and “V2A.”