Marl

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For the town in Germany see Marl, Germany.

A sample of marl

Marls are calcium carbonate or lime-rich muds or mudstones which contain variable amounts of clays and calcite or aragonite. The term is most often used to describe lacustrine (lake) sediments but may also be used for marine deposits. The term 'marl' is widely used in North American geology, while the term seekreide is used in European references.

The lower stratigraphic units of the chalk cliffs of Dover consist of a sequence of glauconitic marl followed by rhythmically-banded limestone and marl layers. Similar upper Cretaceous cyclic sequences in Germany have been correlated with Milankovitch orbital forcing.

Marl is common in post-glacial lake bed sediments, often found underlying peat bogs. It has been utilized as a soil conditioner and acid soil neutralizing agent.

[edit] References

• Schurrenberger, D., Russell, J. and Kerry Kelts. 2003. Classification of lacustrine sediments based on sedimentary components. Journal of Paleolimnology 29: 141-154.
• Chalk of Kent by C. S. Harris Accessed 11/06/2005
• Geochemistry and time-series analyses of orbitally forced Upper Cretaceous marl–limestone rhythmites, abstract Accessed 11/06/2005
• Palaeoenvironmental Interpretation of the Early Postglacial Sedimentary Record of a Marl Lake Accessed 11/06/2005

[edit] See also

• Agricultural lime