France. Service de la carte geologique de France North Decimal Degree 48.3569 South Decimal Degree 47.9975 East Decimal Degree -1.5516 West Decimal Degree -2.4139 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."