World Data Service for Geophysics

Marine Trackline Geophysical Data

Trackline Geophysical Data Viewer

NCEI's Marine Trackline Geophysical database provides bathymetry (single-beam), magnetics, gravity and seismic reflection data collected during marine cruises from 1939 to the present. Data sources include US and non-US oceanographic institutions, universities, and government agencies with worldwide data coverage.

Locating and Downloading Data

Data are available via the Trackline Geophysical Data Viewer. Search by geographic area, year of survey, institution, platform, survey name, date added to the database, and data type are available. Downloads can be customized to area, data type, and format.

Data can be exported in the MGD77T Exchange Format, which contains a documentation header record and data records. Header records provide metadata for each survey. Data records contain geophysical data (bathymetry, magnetics, gravity, and seismic shot-point IDs) with time and position. MAG88T Exchange Format is used for airborne magnetic surveys, aeromagnetics, for reporting scalar or vector magnetic observations.

Ancillary, analog and high-volume geophysical data, including seismic reflection and refraction, side-scan sonar, are available. Analog data are also provided as scanned image files.

Contributing Data

NCEI accepts contributions of underway geophysical data on almost any media, preferably in the MGD77T Format. Data received become part of the international public domain, available to anyone. Proprietary data can also be archived at NCEI. If you would like to contribute data, contact