steam and water percolating from the spiteful geyser and fan geyser in yllowstone national park

basin boiling caldera continental crater divide ecology environment fan firehole fumes geologic geology geothermal geyser grassland heat hot landmark landscape mineral mortar national natural nature outdoors outside park percolating pool river rock scenic sky spiteful spouting spring states steam steaming sulphur thermal trail travel united upper usa vacation vapor volcanic volcano water wild wilderness wyoming yellowstone