Margerie Glacier - Glacier Bay National Park
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Margerie Glacier - Glacier Bay National Park Glacier Bay is the end result of the Little Ice Age which reached its maximum advance in about 1750. Today you must travel 65 miles from Juneau to Glacier Bay to view tidewater glaciers. Park Headquarters is at Bartlett Cove where additional information is available.
Park Rangers board Cruise ships traveling up the bay, their presentation is well worth attending. Information they provide will assist you in answering the questions posed as logging requirements. The following is taken from Wikipedia Website with additional information provided by Glacier Bay Park Staff: Glacier Bay National Park and Preserve is a United States National Park. located in the southeastern part of Alaska west of Juneau. The area around Glacier Bay was first proclaimed a US National Monument on February 25, 1925. It was changed to Glacier Bay National Park and Preserve on Dec. 2, 1980 by the Alaska National Interest Lands Conservation Act. The park area was included in an International Biosphere Reserve in 1986 and is part of a UNESCO World Heritage Site. The park covers 5,130 mi² (13,287 km²). Most of the park is a designated wilderness area which covers 4,164 mi² (10,784 km²) of the park. No roads lead to the park and it is most easily reached by air travel. During some summers there are ferries to the small community of Gustavus or directly to the marina at Bartlett Cove. Despite the lack of roads, there are over 400,000 visitors per year, most on cruise ships. Glaciers descending from high snow capped mountains into the bay create spectacular displays of ice and iceberg formation. In the last century, the most dramatic was probably the Muir Glacier. The calving face was nearly 2 mi (3.2 km) wide and about 265 ft (81 m) high. In the 1990s, the Muir Glacier receded to the point that it was no longer a tidewater glacier. Most visitors today see the Margerie and Lamplugh Glaciers. Glacier Bay and the Marjorie Glacier are approachable only by air and water. The steep dropoff of the Margerie Glacier cliff facilitates large cruise ships to park close to the glacier from where one gets incredible views of the glacier. Margerie Glacier, at the deep end of the Glacier Bay, is named for the famed French geographer and geologist Emmanuel de Margerie (1862–1953), who visited the Glacier Bay in 1913. The glacier extends over a width of about 1 mile (1.6 km) and extends upstream for a length of 21 miles (34 km) till its source on the southern slopes of the hill of Mount Root, at the Alaska-Canada border. It flows southeast and northeast to Tarr Inlet, named in 1912 for professor of geology Dr. Ralph Tarr. This Inlet is one mile (1.6 km) north of the terminus of Grand Pacific Glacier and 87 miles (140 km) northwest of Hoonah; a Tlingit community 30 miles west of Juneau, across the Alaskan Inland Passage on Chichagof Island, located in Alaska’s "panhandle" in the southeast region of the state. The Glacier Bay region, which in 1750 was a mass of ice of a single glacier, has undergone a dynamic change and is now a 65-mile long fjord. Mount Root (elevation 12,860 feet (3,920 m)), named Boundary Peak 165, is a mountain in Alaska and British Columbia, is part of the Fairweather Range (Mt. Fairweather is the tallest peak with elevation of15,325 feet (4,671 m)) of the Saint Elias Mountains. It is named after Elihu Root, who was among the diplomats involved in settling the Alaska boundary dispute between the United States and Canada. While most of the tidewater and terrestrial glaciers in the Park are stated to be thinning and receding over the last several decades, Margerie Glacier is said to be stable and John Hopkins Glacier is stated to be advancing, on the eastern face of the Fairweather Range. In a study of the bed rock geology and mineral resources of the Glacial Bay, out of 17 areas classified as containing mineral deposits, Marjerie Glacier has been identified as containing copper deposits. History of the Margerie Glacier is integral to the history of Glacier Bay. In 1794, Glacier Bay was a wall of ice when Captain Vancouver was blocked in his explorations by a wall of 2 miles (3.2 km) width and 4,000 feet (1,200 m) thick. 88 years later, when in 1879 John Muir had first visited the bay, this wall was 48 miles and had retreated by 44 miles (71 km). Now, it has retreated to 65 miles as a remnant of the old wall of the glacier system and has 16 major tidewater glaciers. Margerie Glacier, categorized as a typical example of tide-water glacier (tidewater glacier is defined as a glacier which generates sufficient snow to flow out from the mountains to the sea, has a total height of 350 feet (110 m), out of which 250 feet (76 m) raises above the water level and 100 feet (30 m) is beneath the water surface. (This height is stated to be larger than the 307 feet (94 m) high Statue of Liberty). The glacier exhibits a distinctive curved layer of rock debris mixed with ice. The glacier has impressive configurations (as if carved with hand tools), in a "jagged and twisted form", set in ice which is seen in blue color as a result of absorption of rays of shorter red and green wavelengths. It is a much cleaner glacier as compared to other glaciers in the Glacier Bay. It is also one of the most active glacier for "Calving" (a word meaning breaking and dropping of ice walls into the sea). As the glacier calves, "a rifle-like crack and a booming roar is heard creating a boiling like turbulence." Some times, ice caves get formed in the glacier, which is considered highly unstable since blocks of ice collapse into the water from the sides of the cave formation and create a resounding noise as it splashes. The glaciers in the Glacier Bay are stated to be remnants of a general "ice advance – the Little Ice Age – that began about 4,000 years ago". This advance is not comparable to continental glaciation that occurred during "Pleistocene times known as the Wisconsin Ice Age". However, about 1750, the 'Little Ice Age' reached its maximum stage and then melting started. Ice flows have been recorded at Marjorie Glacier 2,000 feet (610 m) per year or 6 feet (1.8 m) per day. Its advance was reported to be at the rate of 30 feet (9.1 m) per year till 1998 when some degree of recession has been noticed at its northern terminus "forming a small embayment," while the southern part is advancing at 1 foot (0.30 m) per year. In the 1990s, the glacier was attached to the Grand Pacific Glacier. However, it is now detached from the Grand Pacific (which is said to be receding) and moranic material is seen where it has separated on its northern extremity, discerned by a small stream. As result, the Margerie Glacier is considered to be stable and is termed "a hanging glacier with its base about 600 feet (180 m) above the floor of Tarr Inlet near its center." Fresh water 'upswellings' are seen to emerge from the central area of the glacier, generated by the melt water discharges of sub glacial streams; such areas are swarmed by sea birds for feeding on fish. To record this find send us an email with answers to the following: Do not post this information in your log 1) The name of your ship and the number of people in your party 2) describe the weather conditions on the date and at the time you were near to the glacier. 3) estimate the distance you are away from the face of the glacier 4) Is Margerie Glacier receding, advancing or stable? Briefly explain the reason(s) for your answer. 5) name a flower that is among the first plants that pioneer the recovery of bare, disturbed land left behind when a glacier recedes. (This answer can be found in the pamphlet available at the Park Ranger's Presentation) Additional but not a requirement: post a photo of Margerie Glacier with your GPSr or a photo of the glacier taken from your ship showing a portion of the ship in the photo
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