France. Service de la carte geologique de France North Decimal Degree 48.4121 South Decimal Degree 48.0586 East Decimal Degree 4.4989 West Decimal Degree 3.6345 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."