Scidmore Bay, enclosed by the Gilbert Peninsula to the east and the Fairweather Mountains to the west, lies in Glacier Bay National Park and Preserve, about 119 miles (192 km) southeast of Yakutat and 43 miles (69 km) northwest of Gustavus, Alaska. The bay is named after Eliza Scidmore, pronounced ‘Sidmore’. Gilbert Island—now Gilbert Peninsula after post-glacial rebound raised the connecting isthmus—was renamed in 1937 by William O. Field and William S. Cooper for Grove K. Gilbert, a US Geological Survey geologist who visited Glacier Bay with the Harriman Expedition in 1899. Scidmore Glacier once flowed into the bay; today only a small remnant remains about 4 miles (6.5 km) up the Scidmore River valley at 3,850 feet (1,174 m) on a ridge east of Reid Glacier. Glaciologists, hydrographers, ecologists have long studied the retreat of the vast Glacier Bay Icefield, observed by George Vancouver (1794), John Muir (1879), Eliza Scidmore (1883) and Grove K. Gilbert (1899). At its Little Ice Age peak around 1750, the icefield spanned over 1.48 million acres (600,000 ha) and reached up to 4,921 feet (1,500 m) thick. Evidence of its former extent is etched on the landscape. Adams Inlet filled with ice and drained east through Endicott Gap into Lynn Canal. Lakes along the glacier flanks and outwash sediments from glacial rivers attest to its reach, forming the Gustavus fan. Scidmore Glacier flowed east from the Fairweather Mountains, merging with the glaciers filling Glacier Bay and leaving only the highest peaks of Gilbert Peninsula exposed. The icefield extended into Icy Strait as a terminal moraine, and its floating terminus destabilized, triggering rapid calving and retreat. In 1794, Lieutenant Joseph Whidbey mapped the icefield terminus when it started receding. Deglaciation spanning 250 years was documented by Reid (1896) and Klotz (1899). In September 1899, an earthquake shattered Muir Glacier’s terminus; within hours, Glacier Bay became a mass of floating ice that halted vessel excursions and ships could only approach within 5 miles (8 km).

Scidmore Glacier, often overlooked by visitors, commemorates one of the region’s most intrepid explorers. Eliza Ruhamah Scidmore was an independent world traveler, writer and diplomat. Born in 1856 in Iowa, she attended Oberlin College and began her career as a newspaper correspondent writing society columns. In the summer of 1883, Scidmore purchased a ticket to Alaska. She journeyed through Southeast Alaska on the steamship Idaho, commanded by Captain James Carroll, and became one of the first tourists to visit Glacier Bay. Her travel accounts conveyed Alaska’s grandeur and adventure, opening the region to tourism. In 1885 she published the first Alaska travel guide, Alaska, its Southern Coast and the Sitkan Archipelago, followed in 1890 by Guide to Alaska and the Northwest Coast. In subsequent years, Scidmore undertook projects of lasting importance. In 1890 she joined the fledgling National Geographic Society, contributing for 30 years as a writer, editor, photographer and lecturer, and becoming the first woman to serve on its Board of Managers. Her most enduring legacy is the cherry trees in Washington, D.C., planted after her 1885 visit to Japan. Convinced that Japan’s cherry trees would beautify the capital, she collaborated with First Lady Helen Taft, local park officials and Japanese representatives to plant hundreds of trees. Scidmore Glacier—and later Scidmore Bay—were named in 1937 by William O. Field and William S. Cooper in her honor, celebrating the beauty she discovered and shared with the world. See a short video about Scidmore here.

In 1966 the National Park Service requested that the US Geological Survey assess the mineral resource potential of Glacier Bay National Monument for future development. The key economic metals were copper, molybdenum, nickel, gold, silver, titanium and iron. Geologists discovered mineralization at the head of Scidmore Glacier—about 4,000 feet (1,219 m) above sea level—on the eastern headwall of a ridge in the Fairweather Range. The occurrence lies roughly 1 mile (1.6 km) east of Reid Glacier and about 2.3 miles (3.7 km) southeast of the glacier terminus. The area is underlain by a terrane intruded by Cretaceous granitic rocks, with small, localized inliers of Paleozoic schist, phyllite, and marble. Two conspicuously iron-stained zones, up to 25 feet (8 m) thick, cut through tightly folded metasedimentary rocks. Local pyrite-bearing quartz veins, 1 to 2 feet (0.3–0.6 m) thick, intersect these zones. Chalcopyrite was present—a float sample from a quartz vein contained 1,000 ppm copper, while a chip sample from a sulfide zone showed 300 ppm copper and 7 percent iron, but no gold or silver. Today, mining in national parks is regulated under the Mining in the Parks Act of 1978. Any mining or mineral-extraction activity in a park requires approval of a Plan of Operations that includes an environmental impact analysis. Meanwhile, the Alaska Mineral Resource Assessment Program—mandated by the Alaska National Interest Lands Conservation Act of 1980 and led by the US Geological Survey—assesses mineral resources across the state, including within national park units, to identify deposits critical for national security and economic health. Read more here and here. Explore more of Scidmore Bay and Gilbert Peninsula here: