Miage Glacier

Miage Glacier
The ends of the Miage Glacier's terminal lobes at sunset, as seen from northeastern Val Veny in August 2010

The Miage Glacier is a debris-covered glacier in northwestern Italy. It is situated on the southwest flank of the Mont Blanc massif, flowing from Col de Bionnassay (3,892 m (12,769 ft) above sea level) into Val Veny. At around 10 km (6.2 mi) in length, it is Italy's longest glacier and also the largest debris-covered glacier in Europe.[1] Approximately 5 km2 (1.9 sq mi) of its total area of ~11 km2 (4.2 sq mi) is covered in debris originating primarily in rockfall from surrounding walls[2] and avalanching in accumulation areas of its four tributaries.[3] Debris carried along within the glacier is also being exposed at increased rates due to accelerating thinning of the glacier tongue.[3]

The number of sources of supraglacial debris as well as the unusual, mica schist-dominated lithology of the rock walls surrounding the glacier, makes for a varied debris lithology; debris cover becomes continuous at ~2,400 m (7,900 ft) above mean sea level (asl) and remains unbroken to the terminus. Patchy areas can occur, however, where crevasses or moulins occur.[3] Debris thickness generally increases from a few centimetres at 2,400 m (7,900 ft) asl to over 1 metre (3 ft 3 in) at the terminus at ~1,775 m (5,823 ft) asl, although the spatial distribution of thicknesses is heterogeneous especially on parts of the northern terminal lobe.[4]

Miage Lake

View of Miage Lake from the west, summer 2010

Miage Lake is an ice-contact lake near the southern end of the Miage Glacier, located on the outside of the glacier's 90-degree bend eastwards.[3] It is a popular tourist attraction due to the spectacular ice cliffs rising up to one side and its two-coloured appearance. The colours reflect varying sediment concentrations in the water which arise as a result of the filtering effect of the debris.[5]

Huge ice blocks have been known to break off the glacier and fall into the lake, providing another major tourist attraction despite the low chance of such an event occurring. On August 7, 1996, a particularly large block, estimated to have had a volume of 7000-16000m3, fell into the lake causing an abnormally large wave that seriously injured several people.[6]

References

  1. ^ Deline, P. (2005). "Change in surface debris cover on Mont Blanc massif glaciers after the 'Little Ice Age' termination". The Holocene 15 (2): 302. doi:10.1191/0959683605hl809rr.  edit
  2. ^ Deline, P. (2009). "Interactions between rock avalanches and glaciers in the Mont Blanc massif during the late Holocene". Quaternary Science Reviews 28: 1070–1083. Bibcode 2009QSRv...28.1070D. doi:10.1016/j.quascirev.2008.09.025.  edit
  3. ^ a b c d Mihalcea, C.; Brock, B.; Diolaiuti, G.; Dagata, C.; Citterio, M.; Kirkbride, M.; Cutler, M.; Smiraglia, C. (2008). "Using ASTER satellite and ground-based surface temperature measurements to derive supraglacial debris cover and thickness patterns on Miage Glacier (Mont Blanc Massif, Italy)". Cold Regions Science and Technology 52: 341. doi:10.1016/j.coldregions.2007.03.004.  edit
  4. ^ Brock, B. W.; Mihalcea, C.; Kirkbride, M. P.; Diolaiuti, G.; Cutler, M. E. J.; Smiraglia, C. (2010). "Meteorology and surface energy fluxes in the 2005–2007 ablation seasons at the Miage debris-covered glacier, Mont Blanc Massif, Italian Alps". Journal of Geophysical Research 115: D09106. Bibcode 2010JGRD..11509106B. doi:10.1029/2009JD013224.  edit
  5. ^ "SwissEduc: Glaciers Online - Glacier du Miage". Swisseduc.ch. 2008-01-28. http://www.swisseduc.ch/glaciers/alps/miage/index-en.html. Retrieved 2010-09-13. 
  6. ^ Tinti, S.; Maramai, A.; Cerutti, A. (1999). "The Miage Glacier in the Valley of Aosta (Western Alps, Italy) and the extraordinary detachment which occurred on August 9, 1996". Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy 24 (2): 157. Bibcode 1999PCEA...24..157T. doi:10.1016/S1464-1895(99)00012-5.  edit

Coordinates: 45°48′15″N 6°50′26″E / 45.80417°N 6.84056°E / 45.80417; 6.84056


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • Glacier Du Miage — Glacier du Miage vu du secteur du lac Chécroui. La zone boisée enserrée par le glacier recouvert de rochers s appelle le Jardin du Miage. En arrière plan, le glacier de la Lée blanche. Latitude Longitude …   Wikipédia en Français

  • Glacier du miage — Glacier du Miage vu du secteur du lac Chécroui. La zone boisée enserrée par le glacier recouvert de rochers s appelle le Jardin du Miage. En arrière plan, le glacier de la Lée blanche. Latitude Longitude …   Wikipédia en Français

  • Glacier de Tré la Tête — Vue de la partie centrale du glacier. Latitude Longitude …   Wikipédia en Français

  • Glacier du Miage —  Ne doit pas être confondu avec le glacier de Miage qui se trouve sur le versant français. Glacier du Miage …   Wikipédia en Français

  • Glacier du Miage — Oberer Bereich des Gletschers, im Vordergrund der Lac du Miage Zunge des Gletschers mit dem Giardino del Miage, also dem Wald zwischen den Zungenteilen Der Ghiaccia …   Deutsch Wikipedia

  • Miage-Gletscher — Oberer Bereich des Gletschers, im Vordergrund der Lac du Miage Zunge des Gletschers mit dem Giardino del Miage, also dem Wald zwischen den Zungenteilen Der Ghiaccia …   Deutsch Wikipedia

  • Glacier de Miage —  Ne doit pas être confondu avec le glacier du Miage qui se trouve sur le versant italien. Glacier de Miage Latitude Longitude …   Wikipédia en Français

  • Glacier de Bionnassay —  Ne doit pas être confondu avec le glacier du Bionnassay Italien Glacier de Bionnassay Vue du glacier depuis le …   Wikipédia en Français

  • miage — (LE GLACIER DE) nm. npr. l glyassî dè Myazho (Albanais) …   Dictionnaire Français-Savoyard

  • Glaciar de Miage — Se ha sugerido que este artículo o sección sea fusionado con Glaciar de Miage (Francia) (discusión). Una vez que hayas realizado la fusión de artículos, pide la fusión de historiales aquí …   Wikipedia Español

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”