One of the geological high points...

of the month-long voyage was seen today at Yankicha Island, and all of a sudden I was the most popular naturalist on the expedition. The bubbling hot springs and stinking fumaroles overwhelmed the senses as passengers began exploring this fascinating area:

Sinter mounds contained basins filled with vigorously boiling water, and one needed to exercise some degree of caution when approaching these features:

And sulfur crystals are found lining dozens of actively venting fumaroles:

In addition, arctic foxes are common on the island, and are not the least bit shy. They have no predators and will approach within several feet, and they'll even "mark" your stuff if you leave it unattended on the ground and turn your back: