Blue Fjord is a glacial estuary on the east coast of the Kenai Peninsula, that trends north for 4.5 miles (7.3 km) to Port Nellie Juan, in Prince William Sound, about 26 miles (42 km) southeast of Whittier, Alaska. The bay was named in 1909 by the U.S. Geological Survey for the color of the glacier at the head of the fjord.
Ultramarine Glacier is located at the head of Blue Fjord. The glacier flows out of the Sargent Icefield and then trends northeast for 2 miles (3.2 km) to its terminus at the head of a 1.4 miles (2.3 km) long proglacial lake. The terminus is surrounded by an apron of stagnant ice covered by moraine gravel and a fringe of vegetation-free bedrock. A stream of about 1 mile (1.6 km) connects the lake to Blue Fjord.
The Ultramarine Glacier filled Blue Fjord during the Pleistocene which lasted from about 2,588,000 to 11,700 years ago. A series of advances and retreats have likely occurred since then. The most recent advance was documented using a carbon isotope sequence from logs at the head of Blue Fjord. The logs helped determine that the glacier had a length of 5.6 miles (9 km) and an area of 7,413 acres (3,000 ha) in about 1880 to 1890. In 1908, the glacier was observed within about 0.25 miles (0.5 km) of tidewater and had retreated about 1300 feet (400 m). Subsequent observations documented a retreat of another 1000 feet (300 m) by 1935, and another 1000 feet (300 m) by 1964, and 1.2 miles (2 km) between 1964 and 2000. Read more here and here. Explore more of Blue Fjord here: