Embry and Clovan classification

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Embry and Clovan classification A limestone classification, based on textural principles, which expands the Dunham classification to include conglomeratic limestones and different types of organically bound limestone. E. F. Embry and J. E. Clovan proposed their system in 1971. They retain the Dunham terminology of mudstone, wackestone, packstone, and grainstone for limestones with particles less than 2mm in size, but for limestones containing particles more than 2mm in size they define two new terms: floatstone (matrix-supported limestone in which more than 10% of the clasts are larger than 2mm in size); and rudstone (clast-supported limestone in which more than 10% of the clasts are coarser than 2mm in size). For autochthonous limestones whose original components were organically bound during deposition Embry and Clovan replace the Dunham term ‘boundstone’ with three new terms: bafflestone (autochthonous limestone whose original components were bound during deposition by organisms which act as baffles, permitting sediment to be trapped in the lee of the baffles); bindstone (autochthonous limestone whose original components were bound during deposition by organisms which encrust and bind, e.g. algae); and framestone (autochthonous limestone whose original components were bound during deposition by organisms which built a rigid framework, e.g. corals (Anthozoa) in a reef structure).

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Embry and Clovan classification

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