User:DCDuring/Dunham classification of sedimentary stone
Jump to navigation
Jump to search
- mudstone contains less than 10% grains (usually assessed by area in cut or thin section), supported by a lime mud.
- wackestone consists of more than 10% grains, supported by a lime mud.
- packstone contains lime mud and is grain supported.
- rudstone is coarse limestones supported by grains larger than 2 mm.
- grainstone lacks mud and is grain supported.
- floatstone contains over 10% >2mm grains but is matrix supported
- boundstone Boundstone describes sediment where the original components have been bound together during deposition.
- bafflestone develops where organisms have acted as baffles during deposition, reducing the local depositional energy. They will contain traces of baffling organism and smaller grains than would be expected from the paleocurrent strength.
- bindstone is produced where organisms (such as algae) encrust the elements during deposition and bind them together.
- framestone is a solid calcareous or siliceous framework which is maintained by an organism such as a coral or sponge.
- crystalline carbonate does not have recognisable depositional structures.