hverir geothermal steam chimney

205°c 400°f active air alien area boiling caldera chimney crater egg filled fills fumaroles fume fuming furarole gas geothermal geothermally geothermaly ground gurgling hissing hot hverir krafla landscape moon-like mud myvatn mývatn plumes pools reach ring road rock rotten sand smoldering steam steaming stench sulfur temperatures tower vents volcanic wind