Seismograph and Bluebell Pools are located at the West Thumb Geyser Basin in Yellowstone. The two pools are blue in color. The Seismograph pool occasionally collects mud from nearby mudpots. Both can be viewed from the outer loop of the Trail. A steep grade connects the outer loop boardwalk with the inner loop. The two pools are located next to that grade. The bright blue color is due to extremely high temperatures, usually around 165 degrees F.

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The Old Faithful and Upper Geyser Basin Biscuit Basin West Thumb Geyser Basin Thumb Paint Pots Lakeshore Geyser and Lakeside Spring Seismograph and Bluebell Pools Fishing Cone Black Pool Is Bright Blue in Color Yellowstone Lake The South Entrance Offers a Dramatic Way into Yellowstone Mammoth Hot Springs - Tips for Travelers Minerva Terrace The Colorful Palette Spring Liberty Cap Petrified Tree in Yellowstone Wildlife Watching along the Blacktail Plateau Drive Romantic Sunset at the Great Fountain Geyser Undine Falls and The Upper Falls

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