Mudstone vs. Shale — What's the Difference?

Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Mudstone is distinguished from shale by its lack of fissility (parallel layering).The term mudstone is also used to describe carbonate rocks (limestone or dolomite) that are composed predominantly of carbonate mud.

Shale is a fine-grained, clastic sedimentary rock, formed from mud that is a mix of flakes of clay minerals and tiny fragments (silt-sized particles) of other minerals, especially quartz and calcite. Shale is characterized by its tendency to split into thin layers (laminae) less than one centimeter in thickness.

A fine-grained, dark gray sedimentary rock, formed from silt and clay and similar to shale but without laminations.

Soft finely stratified sedimentary rock that formed from consolidated mud or clay and can be split easily into fragile plates.

(petrology) A fine-grained sedimentary rock whose original constituents were clays or muds.

A fissile rock composed of layers of claylike, fine-grained sediments.

A shell or husk; a cod or pod.

(geology) A fine-grained sedimentary rock of a thin, laminated, and often friable, structure.

To take off the shell or coat of.

A shell or husk; a cod or pod.

A fine-grained sedimentary rock of a thin, laminated, and often friable, structure.

To take off the shell or coat of; to shell.

A sedimentary rock formed by the deposition of successive layers of clay