World Library  
Flag as Inappropriate
Email this Article

Moulin (geology)

Article Id: WHEBN0003123653
Reproduction Date:

Title: Moulin (geology)  
Author: World Heritage Encyclopedia
Language: English
Subject: Glacier, Langjökull, List of landforms, Moulins, Greenland ice sheet, Melt pond, Giant's kettle, Jakobshavn Glacier, Tunnel valley, Cavaglia
Publisher: World Heritage Encyclopedia

Moulin (geology)

A hiker peers into a massive moulin on Snowbird Glacier, in the Talkeetna Mountains of Alaska
Schematic drawing of glacial features illustrating how moulins transport surface water to the base of the glacier
Surface water entering a moulin on Athabasca Glacier

A moulin or glacier mill is a roughly circular, vertical to nearly vertical well-like shaft within a glacier through which water enters from the surface. The term is derived from the French word for mill.[1]

They can be up to 10 metres wide and are typically found at a flat area of a glacier in a region of transverse crevasses.[2] Moulins can reach the bottom of the glacier, hundreds of metres deep, or may only reach the depth of common crevasse formation (about 10–40 m) where the stream flows englacially.[2] They are the most typical cause for the formation of a glacier cave.

Moulins are a part of a glacier's internal "plumbing" system, that carry meltwater from the surface down to wherever it may go.[3] Water from a moulin often exits the glacier at base level, sometimes into the sea, and occasionally the lower end of a moulin may be exposed in the face of a glacier or at the edge of a stagnant block of ice.

Water from moulins may help lubricate the base of the glacier, affecting glacial motion. Given an appropriate relationship between an ice sheet and the terrain, the head of water in a moulin can provide the power and medium with which a tunnel valley may be formed. The role of water in lubricating the base of ice sheets and glaciers is complex. Difficulties modelling this process led to apparently over-optimistic predictions of sea level rise by the IPCC in the IPCC fourth assessment report.

See also


  1. ^ Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, J.A., eds. (2005) Glossary of Geology (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. ISBN 0-922152-76-4
  2. ^ a b "Moulin 'Blanc': NASA Expedition Probes Deep Within a Greenland Glacier". Earth Observatory. NASA. Dec 11, 2006. Retrieved 2009-06-17. 
  3. ^ Amos, Jonathan (Dec 21, 2008). "Explorers dive under Greenland ice". BBC News. Retrieved 2009-06-17. 

External links

  • Earth Observatory page.
  • December 2006 article about a NASA expedition to Greenland moulin.
  • Moulins in Greenland (Google)
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.