File:Morning Glory Pool 1.jpg

English: Morning Glory Pool, Morning Glory Group, northern Upper Geyser Basin, Yellowstone Hotspot, northwestern Wyoming, USA.

The natural appearance of Morning Glory Pool was basically all blue, resembling a morning glory flower. The hottest of Yellowstone’s hot spring pools are bluish-colored - the high temperatures knock out even heat-loving extremophile bacteria, so the yellowish-orangish-reddish colored bacterial mats are absent. Incessant tossing of garbage into the pool by brainless tourists over many decades has significantly damaged this feature. Park personnel have removed trash and coins on several occasions. Unretrieved trash deep in the vent has restricted water movement, resulting in cooling and the loss of the pale blue coloration. The green coloration shown above results from “bluish water” mixed with yellowish-colored bacterial mats. When the pool is hotter, bacteria don’t live near the center (see below). Morning Glory Pool was originally surrounded by a geyserite border, which was completely removed by early tourists. 30 July 2012 (looking ~NE).

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