colorful abyss pool near yellowstone lake at west thumb geyser basin, yellowstone national park, wyoming

abyss algae america american background basin beautiful black caldera clear color colorful colour colourful expanse forest geological geology geothermal geyser geyserite heritage hike hiking hot lake landscape many morning most mountains national natural nature north of outdoor outdoors park plateau pool pools river rocky runoff shores site spring springs states still tectonics thumb trail trees turquois unesco united upper usa volcanic volcanism water west western wild wilderness world wyoming yellow yellowstone