silurian

/sai'ljuəriən/

Thân thiện

The paleontologist carefully examines a Silurian fossil embedded in rock.

Definition

1. Proper noun:
   • A geological period: The Silurian is a specific period in Earth's history, part of the Paleozoic Era, occurring approximately between 443 and 419 million years ago. It is known for significant developments in marine life and the first appearance of air-breathing animals on land.

Examples of Usage

• Proper noun:
  • Fossils from the Silurian period show the diversification of early coral reefs.
  • Geologists study rock formations that date back to the Silurian.

Advanced Usage

• "Silurian rocks": Sedimentary rock layers deposited during the Silurian period.
  • The quarry exposes excellent examples of Silurian rocks.
• "Silurian fauna": The collective animal life that existed during the Silurian period.
  • The museum has a display dedicated to Silurian fauna, including early jawless fish.

Variants and Related Words

• Silurian Period: The full formal name for this geological time unit.
• Silurian System: In stratigraphy, the set of rock strata corresponding to the Silurian period.

Synonyms

• Silurian Period: (The term is a proper name for a specific time interval; it has no true synonym but can be referred to descriptively.)

Related Phrases

• Post-Silurian: Referring to time or rocks after the Silurian period.
  • These fossils are from a post-Silurian deposit.
• Pre-Silurian: Referring to time or rocks before the Silurian period.
  • Pre-Silurian continents had very different configurations.

Học thuật

Noun

1. from 425 million to 405 million years ago; first air-breathing animals

Từ đồng nghĩa

• Silurian
• Silurian period