Terms of use
Disclaimer
Data, products or software available at BGI are mostly dedicated to support scientific and academic activities.
You may not distribute or publish materials you obtained from this site if you do not accept the Terms of use
Digital gravity data or products are distributed free of charge to research or academic institutions or to data contributors according to the conditions given below. Other users, individual or private companies, are invited to specify in their request the expected use of the data and products. See BGI website for diffusion and charging policies.
- Access to non-confidential or non-proprietary relative gravity measurements is provided free of charge to public institutions or data contributors over geographic areas limited to 20°x20° or on the base of a maximum number of 10000 data points (land data) and/or 100000 data points (marine data). Retrieval of full data coverage for a whole country is not included in that case. All other requests (for larger datasets, for extended geographic area or for a whole country) as well as massive data retrieval will be subject to an evaluation by BGI who might require a specific protocol of use of the data or ask authorization of the proprietary Institutions. Charges might be applied.
- Access to the Absolute gravity database is provided free of charge. Database consultation and retrieval is done through the Web interfaces at BGI and BKG mirror sites. Confidential data or proprietary data may appear with restricted information (metadata only).
- Access to the Reference gravity stations database (IGSN71 network) is provided free of charge. Note that reference gravity stations (especially those determined and described decades ago) may have been destroyed or modified.
- Access to other additional services is also provided free of charge: global or regional gravity anomaly grids, Prediction of gravity value on Earth, Software, Documentation, etc.
Users of BGI data & Products are invited to make reference to the specific DOI (Digital Object Identifier) provided by BGI along with the distributed data for each query.
Referencing data and get DOI
The contribution of countries, agencies and scientists involved in surface gravity data acquisition (relative or absolute measurements from field, marine or airborne surveys) is essential for improving the global coverage and accuracy of the Earth gravity field and for contributing to the determination of the new International Gravity Reference Frame (IGRF). The archiving of such incoming gravity sets also enables BGI to better validate the gravity observations in a global reference frame and restore them in standard and unified formats useful for the end users. Contributors interested in archiving their gravity observations or derived products as non-confidential or as proprietary data (to be defined by the contributors themselves) are invited to contact BGI.
A Digital Object Identifier (DOI) will be delivered to any institution or author for archiving their own dataset resulting from gravity survey or gravity data compilation. This new service aims at ensuring a proper reference and recognition to the authors and institutions who have acquired or compiled gravity data and a better traceability of improvements in the global gravity data coverage from local or regional surveys. DOI attribution may be also extended to relevant software for gravimetric applications (data processing or modeling) or other related information (maps, grids, reports).
- Land, marine or airborne data : Contributors are invited to contact BGI (bgi@cnes.fr). ASCII data files containing all necessary information and quantities are preferred (station coordinates, gravity measurements and accuracies; gravity corrections; reference geographic, height and gravity systems, etc.).
- Absolute gravity data : DOI can be also attributed to Absolute gravity measurements contributing to AGrav database. Agencies or authors interested for archiving their absolute gravity measurements acquired from corner cube or cold-atom measurements are invited to contact either BGI (bgi@cnes.fr) or BKG (agrav@bkg.bund.de). Both laboratories and field measurements are welcome to contribute as parts of the reference and core station and of the national infrastructures building the new International Gravity Reference System & Frame.
For any contribution (relative or absolute gravity data), it is reminded that BGI will keep the status of diffusion (with or without restrictions of redistribution) as specified by the proprietary institution.
Searching gravity survey from DOI or location
BGI delivers a DOI (Digital Object Identifier) to any dataset resulting from gravity survey or gravity data compilation.
A corresponding landing page will be created.
See the DOI Searching Tool for searching gravity campaigns from a given DOI.