France. Service de la carte geologique de France North Decimal Degree 46.9789 South Decimal Degree 46.6190 East Decimal Degree 3.5992 West Decimal Degree 2.7579 Relief shown by hachures. Principal meridian: Paris. Longitude is given in centesimal values (100 grades = 90 degrees) .The Service de la carte geologique de la France was integrated to the BRGM to become the only France Service geologique national. Based on "Carte topograqphique de l'etat major."