To the north of the Vergize bottling facility is the Garrigues de Names, which is made up of limestone rock formed during the Mesozoic era. This limestone developed fissures through the ages, allowing the passage of water. Thes limestone was initially covered with Plaisancian marls from the Tertiary era, then by Quaternary alluvium formed of siliceous sand acting as a filter. This sand was covered more recently by an impermeable layer of clay, which still provides excellent protection for the PERRIER water site.