Base level (on a local, regional or global scale) - the lowest level to which a river can erode - seldom stays
stable for long, in geological terms.
Eustatic changes in base level are due to changes in sea level:
- a rise in sea level following the melting of ice caps
- a fall in sea level as the ice caps develop
Isostatic changes are due to loading and off-loading of the ice caps
- a rise in land level following the melting of ice caps
- a fall in land level as the ice caps develop
Other changes in base level have a tectonic origin.
Land forms associated with a fall in base level result from renewed erosion into the bedrock - rejuvenation -
preserving the original landform but in a modfied form.
Land forms associated with a rise in base level result from flooding by the sea.
Geopix Study Guide "Change in Base Level"
- gives a full image of each of these, and other, examples;
- describes the main landforms which result from a change in base level
Other examples are shown in Geopix Study Guide "Coasts"
The Change in Base Level Study Guide contains the following pages:
'Change in Base Level' is part of the Geopix Weathering and Erosion Study Guide CD.
To order this CD go to the Geopix Online Store
