- World Gravity Map (WGM) is a set of 3 global gravity field anomaly maps computed by the International Gravity Bureau (IGB), a service of the International Association of Geodesy (IAG). This set of digital maps, produced for the Commission of the Geological Map of the World (CGMW), UNESCO, the International Union of Geodesy and Geophysics (IUGG) and the International Union of Geological Sciences (IUGS), represents the first global gravity anomaly maps calculated in spherical symmetry and taking into account a realistic Earth model. Computed from available global gravity field models (EGM08, DTU10), the gravity anomalies presented here (Bouguer, Air-Free, Isostatic) include high-resolution topographic corrections, taking into account the effect of masses related to continents, oceans, inland lakes and seas and ice caps. New theoretical developments have been carried out to enable high-resolution computation on a global scale (Balmino, G., Vales, N., Bonvalot, S. and Briais, A., 2011. Spherical harmonic modeling to ultra-high degree of Bouguer and isostatic anomalies. Journal of Geodesy. DOI 10.1007/s00190-011-0533-4).
- Such anomaly maps, reflecting the density heterogeneities within the Earth (crust, mantle...), are used in many applications in earth physics, structural geology, geodesy (shape of the Earth, geoid), as well as for natural resources exploration (mining and oil exploration). Soon to be available in digital form, they are intended to be updated and disseminated for research and educational purposes.
- This project, led by the Bureau Gravimétrique International (BGI), is the result of a collaboration between various research institutes in different countries (France, Germany, Australia, Denmark, USA).
- The WGM2012 grids (2'x2′ resolution) and the explanatory leaflet in English are downloadable from the International Gravimetric Bureau (BGi) website : http://bgi.omp.obs-mip.fr/data-products/Grids-and-models/wgm2012
World gravity map
Scale 1:50 000 000
Published in 2012
Sets of 3 cards: Bouguer anomalies, isostatic (Airy-Heiskanen), free air on earth surface
Size of each card: 105 x 82 cm
CCGM, BGI, CNES, IRD © 2012
Authors: S. Bonvalot, G. Balmino, A. Briais, M. Kuhn, A. Peyrefitte, N. Vales, R. Biancale, G. Gabalda, G. Moreaux, F. Reinquin and M. Sarrailh
Availability: In stock