A pair of thin layers of clay and silt of contrasting colour and texture which represent the deposit of a single year (summer and winter) in a lake. Such layers can be measured to determine the chronology of glacial sediments.
- ‘Analysis of varves (banded sediments in lakes that show annual variation) can be used to date Pleistocene sediments.’
- ‘These sediments, called varved clays or simply varves, are the primary habitat of Axarus larvae.’
- ‘Each summer/winter pair of layers - called varves - would thus represent a single year.’
- ‘The basal, coarse layer of a varve is commonly overlain by microlaminared silt and clay, reflecting variable streamflow during summer.’
- ‘Some investigators believe the laminated clays are varves and that each couplet represents one year of seasonal deposition.’
Early 20th century; from Swedish varv ‘layer’.
We take a look at several popular, though confusing, punctuation marks.