orange sulfuric soil reach in minerals in leirhnjukur geothermal area in iceland, close-up view

acid active activity area blue clay closeup contamination crater deposit field formation fumarole geology geothermal grey hole hot spring hverarond hverarapara hverir iceland icelandic krafla land landmark leirhnjukur mineral mountain mud pot myvatn natural nature orange oxide red rock soil stone sulfur sulfuric surface terrain tourist travel view volcanic water reach minerals close-up view