boiling mud in namafjall geothermal area, hverir, iceland geothermal area at hverir in the north of iceland near lake myvatn and

active activity akureyri area attraction blue boil boiling bubble clouds crater dramatic energy eruption europe fumarole gas geology geothermal ground heat hot hverarondor hverir iceland icelandic krafla lake lava mineral mountain mud myvatn namafjall near north northeast northern power renewable rocky scenic smell smoke soil spring steam sulfur sulfuric tectonic thermal tourism volcanic volcanism volcano water