The French often call it argilo-calcaire (clay-limestone), which logical enough. The English name, Kimmeridgian Soil, comes from Kimmeridge, an area in the UK with some of these soils. You can actually see fossils in some of the stones! Over the ensuing ages those animals fossilized and left us with soils rich in calcium carbonate from their ancient shells.
Kimmeridgian limestone, aka Kimmeridgian marl, is a mix of limestone and clay made eons ago, where ancient sea creatures (especially the famous comma-shaped oyster, exogyra virgula) died and settled at the bottom of seas - which have long since dried up. Does any other soil appeal to terroir-focused wine drinkers like Kimmeridgian limestone? It's almost magic: key to Chablis Grands Crus and many great Champagnes, you also find Kimmeridgian Limestone in many of Sancerre’s very top wines, especially in and around the hamlet of Chavignol.
