1. a fine-grained sedimentary rock composed primarily of clay and silt particles, formed from the compaction of mud.
Usage: geology; technical

Examples

• The geologist identified mudrock layers in the cliff face.
• Mudrock is one of the most common sedimentary rocks found in the Earth's crust.
• The drilling core revealed alternating bands of sandstone and mudrock.
• Mudrock formations often contain fossils from ancient marine environments.
• This mudrock sample shows evidence of compaction over millions of years.