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Regional Models

France (QGF98)

  Author: H. Duquenne     Created: 1998    Resp: F. L'Ecu  
      Status: PUBLIC    
QGF98 is a gravimetric quasi-geoid model covering mainland France. More specifically, it covers the area 42° < lat < 51.5°, -5.5° < lon < 8.5°, with a grid spacing of 1.5' in latitude and 2' in longitude. The reference ellipsoid is GRS80. The model was computed by using the remove-restore technique with Stokes integration. Three types of data were used for its realization: about 550,000 values of gravity anomalies, most of them from BRGM and BGI, the OSU91A global gravity model and a digital terrain model with a resolution of 140 m. Compared to the previous quasigeoid model, QGF96, about the double number of gravimetric data were utilized. The model was checked by a comparison with 987 GPS/levelling points of the RGF network, showing residuals with a standard deviation of 10.9 cm after detrending.

H. Duquenne (1998). QGF98, a new solution for the quasi-geoid in France. Report of the Finnish Geodetic Institute, 98(4), pp. 251-255.
H. Duquenne (2002). Processus de conversions altimetriques applicables en France. In: Le GPS et les metiers du genie civil - Actes des journees scientifiques du LCPC, pp. 1-10.
IGN (2010). Descriptifs quasi-geoides et grilles de conversion altimetrique sur la France metropolitaine. Laboratoire de Recherche en Geodesie, Service de Geodesie et Nivellement.