Amygdaloid Island

Amygdaloid Island

Amygdaloid Island
Geography
Location	Lake Superior Isle Royale National Park
Coordinates	48°09′04″N 88°37′14″W
Area	0.95 sq mi (2.5 km2)
Administration
United States
Demographics
Population	Uninhabited

Map of Isle Royale and surrounding islands, including Amygdaloid Island (top right).

Amygdaloid Island is an island in Lake Superior off the northeastern shore of Isle Royale. It is within the boundary of Isle Royale National Park, a national park located within the U.S. state of Michigan. The island is protected and patrolled by a seasonal ranger station operated by the U.S. National Park Service.

Geography

Amygdaloid Island is approximately 3.8 miles (6 km) long but no more than 0.25 miles (0.4 km) wide. Like the rest of the Isle Royale archipelago, the island is an ancient ridge of basalt oriented from the southwest to the northeast.

Amygdaloid Island is separated by Amygdaloid Channel from Isle Royale. It had relatively low visitation until the 1990s, when the growth of sea kayaking made it possible for human-powered visitors to approach the island. The waters of Lake Superior around Amygdaloid Island are notoriously dangerous, and inexperienced kayakers are not encouraged to navigate them.

Geology

The island is the site of the Amygdaloid Island Flow, a deposit of basaltic lava with silica inclusions. After the lava cooled, the inclusions hardened into pink agate specimens. The agates of Amygdaloid Island are characteristically almond-shaped or amygdaloidal, hence the name Amygdaloid.

See also

• List of islands in Isle Royale National Park