OZCAR-RI SNO_KARST Mediterranean and coastal site of Port-Miou - France
OZCAR-RI SNO_KARST Mediterranean and coastal site of Port-Miou
The Mediterranean and coastal site of Port-Miou is a wide regional carbonate aquifer, with a catchment area around 400 km², in south of France (Provence, France). It extends mainly over natural land, in the vicinity of one of the main city of France (Marseille), facing recent urban expansion and future groundwater resources management issues. Top of the recharge area culminates at 1100 m asl, and the main outlets are submarine springs. Karst features are observed in surface (polje, intermittent rivers, sinkholes, karren, caves) and underground. Many karst networks have been explored in the unsaturated zone of the aquifer, but also in the saturated zone below the sea level. Karst features and conduits drive the groundwater flows to the main outlets. The Port-Miou submarine springs outflow from huge flooded karst conduits, explored by cave diving over several kilometers inland, and to -235 m deep. Groundwater is brackish, polluted by seawater intrusion. The Port-Miou observation site includes flow rate, salinity and temperature monitoring at the main brackish spring, in an in-situ underground laboratory located 500 m inland from the seashore, directly in the main karst conduit. Rainfall is also recording in the catchment area, and rain water samples are collected for water isotopes observation.
General Characteristics, Purpose, History
The Port-Miou site aims to study the water cycle at the catchment scale, in Mediterranean and karst environments. The coastal Port-Miou springs are the main outlets of the regional carbonate aquifer, in southern Provence (400 km²). The site is close to Marseille city, which is more than 1 million inhabitants including its suburban area, with high water demand. Groundwater resources are of major interest. Groundwater flows are widely impacted by karst structures, resulting from speleogenesis linked to the sea level variation at the geological time scale. The main topics of interest are to: - study the saline intrusion in coastal heterogeneous aquifer; - study the speleogenesis in carbonate karst aquifers and the effect on groundwater flow and storage; - study the submarine groundwater discharge to the Mediterranean; - monitor the saline intrusion in the regional aquifer for future assessment of environmental changes.
Port-Miou underground laboratory created in the 1970's. Incomplete data in paper literature.
Affiliation and Network Specific Information