mud volcanoes from berca

berca blue burst buzau clay county crack cracked cracks crater curious desert dirty earth environment erupt eruption europe famous fierbatoarele flowing gas geography geology geothermal grass gray grey ground land landscape liquid mici mineral mountain mud muddy named natural nature oil outdoor pacle paclele park petrol petroleum phenomenon pressure rare reservation romania sediment silt slope sludge slurry soil summer tourism travel volcanic volcano volcanoes