Viedma Glacier is a large

glacier A glacier (; or ) is a persistent body of dense ice, a form of rock, that is constantly moving downhill under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires ...

that is part of the huge

Southern Patagonian Ice Field The Southern Patagonian Ice Field (), located at the Southern Patagonic Andes between Chile and Argentina, is the world's second largest contiguous extrapolar ice field. It is the bigger of two remnant parts of the Patagonian Ice Sheet, which c ...

, located at the southern end of mainland

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

. Viedma Glacier is a

valley glacier Glacier morphology, or the form a glacier takes, is influenced by temperature, precipitation, topography, and other factors. The goal of glacial morphology is to gain a better understanding of glaciated landscapes and the way they are shaped. T ...

and its

moraine A moraine is any accumulation of unconsolidated debris (regolith and Rock (geology), rock), sometimes referred to as glacial till, that occurs in both currently and formerly glaciated regions, and that has been previously carried along by a gla ...

-rich

terminus Terminus may refer to: Ancient Rome *Terminus (god), a Roman deity who protected boundary markers Transport *Terminal train station or terminus, a railway station serving as an end destination *Bus terminus, a bus station serving as an end des ...

flows into the western end of

Lake Viedma Viedma Lake (, ) is a Patagonian lake in the province of Santa Cruz, Argentina, situated near its border with Chile. Measuring approximately 50 miles (80 kilometers) in length, it is a major elongated trough lake formed from melting glacial ice. ...

, which is fed primarily by its melting ice. Viedma Glacier is located in the undefined part of the limit between

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

and

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

, in Argentinian legislature it is in

Los Glaciares National Park Los Glaciares National Park () is a federal protected area in Santa Cruz Province, Argentina. The park covers an area of , making it the largest national park in the country. Established on 11 May 1937, it hosts a representative sample of Mage ...

which was declared a

World Heritage Site World Heritage Sites are landmarks and areas with legal protection under an treaty, international treaty administered by UNESCO for having cultural, historical, or scientific significance. The sites are judged to contain "cultural and natural ...

in 1981. in Chilean legislature part of it is in

Bernardo O'Higgins National Park Bernardo O'Higgins National Park () is the largest of the protected areas in Chile, covering an area of , in both the Aysén del General Carlos Ibáñez del Campo Region, Aysén and Magallanes and Antartica Chilena Region, Magallanes and Antárti ...

. The Southern Patagonian Ice Field is ; Viedma Glacier is one of the Ice Field's 48 outlet glaciers that have more than of ice field area each.

Glacier terminus

Viedma Glacier's

glacier terminus A glacier terminus, toe, or snout, is the end of a glacier at any given point in time. Although glaciers seem motionless to the observer, in reality they are in endless Glacier#Motion, motion and the glacier terminus is always either advancing o ...

is about wide at the point it enters Lake Viedma. Chunks of ice fall off the terminus and float off into the lake, eventually melting. Glacial

moraines A moraine is any accumulation of unconsolidated debris ( regolith and rock), sometimes referred to as glacial till, that occurs in both currently and formerly glaciated regions, and that has been previously carried along by a glacier or ice sh ...

are glacial debris of soil and rock that collect in front of, and along the sides of, the glacier as it flows across the land. The dark parallel lines inside the white central mass of the Viedma Glacier show where the debris-filled moraines have become entwined within the center of the new glacial ice mass as it forms. At right angles to the glacial moraines in the middle,

crevasses A crevasse is a deep crack that forms in a glacier or ice sheet. Crevasses form as a result of the movement and resulting stress associated with the shear stress generated when two semi-rigid pieces above a plastic substrate have different rate ...

, large, canyon-sized cracks, are apparent in the grey-brown ice that can be seen along the sides of the glacier. These cracks are formed from the stress arising between ice along the valley walls (that is slower moving as the friction is greater) and the relatively fast moving ice at the glacier's center. On the southwestern side of the glacier terminus, calving of ice is visible. The glacier terminus ends in a cliff.

Notes

External links

* * {{andean glaciers Glaciers of Chile Glaciers of Magallanes Region Landforms of Santa Cruz Province, Argentina Glaciers of Argentina