Definition

1. Noun:
   • (Geology) A rock composed of broken pieces of older rocks: A clastic rock is a type of sedimentary rock formed from the accumulation and lithification (cementing together) of fragments derived from pre-existing rocks or minerals. These fragments, called clasts, are transported by agents like water, wind, or ice before being deposited and compacted.

Examples of Usage

• Noun:
  • Sandstone is a common clastic rock formed from cemented sand grains.
  • The canyon walls revealed layers of various clastic rocks, telling a story of ancient erosion and deposition.
  • To identify a clastic rock, geologists examine the size, shape, and composition of its constituent particles.

Advanced Usage

• "Clastic" as an adjective: The term "clastic" itself is an adjective describing rocks or sediments composed of fragments. It is often used in geological descriptions.
  • The sedimentary basin is filled with clastic material ranging from fine mud to coarse gravel.

Variants and Related Words

• Clast (n): An individual fragment or grain that makes up a clastic rock.
  • A conglomerate is a clastic rock containing large, rounded clasts.
• Clastic Sediment (n): Unconsolidated, loose fragments before they become rock.
  • Rivers carry clastic sediment downstream to the delta.

Synonyms

• Detrital rock: A synonym often used interchangeably with clastic rock, emphasizing the rock is made of detritus (worn-out fragments).
• Fragmental rock: A descriptive synonym highlighting the rock's composition of fragments.

Related Phrases

• Clastic texture: The physical appearance of a rock defined by its clasts.
  • The clastic texture of the sandstone indicated it was deposited by fast-moving water.
• Clastic sequence: A series of layered clastic rocks.
  • The drill core sampled a thick clastic sequence from the Mesozoic era.

Noun

1. (geology) a rock composed of broken pieces of older rocks