Definition

Noun: A fine-grained sedimentary rock composed primarily of consolidated silt-sized particles. It is a type of clastic rock that falls between shale (finer particles) and sandstone (coarser particles) in terms of grain size.

Usage

Siltstone is a specific geological term used to describe a rock type. It is typically used in academic, scientific, and industrial contexts related to geology, sedimentology, and construction materials. - The cliff face revealed layers of siltstone and shale. - Geologists analyzed the siltstone sample to determine its age and composition. - This siltstone is too soft to be an effective building stone.

Advanced Usage

• "Flaggy siltstone": Siltstone that splits into thin, flat layers or slabs.
  • The quarry produces flaggy siltstone used for garden paving.
• "Calcareous siltstone": Siltstone containing a significant amount of calcium carbonate.
  • The calcareous siltstone reacted with the acid, indicating the presence of carbonate minerals.

Variants and Related Words

• Silt (n): The unconsolidated sediment particles from which siltstone forms.
  • The river delta is composed of fine silt and clay.
• Silty (adj): Having the qualities of or resembling silt.
  • The soil has a silty texture.

Synonyms

• Mudstone (Note: Mudstone is a closely related fine-grained rock but may contain a higher proportion of clay-sized particles than typical siltstone.)
• Argillite (Note: A more general term for a compact, fine-grained sedimentary rock.)

Related Phrases

• Siltstone formation: A distinct layer or body of siltstone within a sequence of rocks.
  • The fossil was found in a siltstone formation dating to the Devonian period.
• Siltstone member: In stratigraphy, a named subdivision of a geological formation that is primarily siltstone.
  • The shale formation includes a prominent siltstone member near its base.

Noun

1. a fine-grained sandstone of consolidated silt