Skip to page content |

Tiscali Quicklinks. Please visit our Accessibility Page for a list of the Access Keys you can use to find your way around the site, skip directly to the main navigation, to the page content, or to more links within reference.

Advertisement starts



Advertisement ends

Content Starts Here


freeze–thaw

encyclopaedia header
Encyclopaedia Search
Click a letter for the index
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Or search the encyclopaedia:
 
 
 
all results tagged with the © symbol denotes content that is relevant to the national curriculum

Freeze–thaw

Compassberg, South Africa - Click to enlarge rockfalls on the Dorset coast - Click to enlarge scree slopes - Click to enlarge scree slopes, Lake District - Click to enlarge

Click images to enlarge

Form of physical weathering, common in mountains and glacial environments, caused by the expansion of water as it freezes. Water in a crack freezes and expands in volume by 9% as it turns to ice. This expansion exerts great pressure on the rock, causing the crack to enlarge. After many cycles of freeze–thaw, rock fragments may break off to form scree slopes.

For freeze–thaw to operate effectively the temperature must fluctuate regularly above and below 0°C/32°F. It is therefore uncommon in areas of extreme and perpetual cold, such as the polar regions.

© Research Machines plc 2008. All rights reserved. Helicon Publishing is a division of Research Machines plc.


 
 

Advertisement starts



Advertisement ends


Advertisement starts



Advertisement ends

Page Footer


Access keys


You will need to use different key combinations in order to use access keys depending on your internet browser, find out which on our accessibility page.
  • (0) Navigate to Accessibility page.
  • (1) Navigate to Home page.
  • (2) Navigate to My email.
  • (3) Navigate to My Account.
  • (4) Navigate to Site Map page.
  • (5) Navigate to Contact us page.
  • (6) Navigate to Members channel.
  • (7) Navigate to Services channel.
  • (8) Navigate to News & Info channel.
  • (9) Navigate to Entertainment channel.
  • ([) Skip down to the Primary navigation block.
  • (]) Skip down to the more links within this section block.
  • (=) Bypass all navigation and jump to the content.