Oligocene

/ɔ'ligousi:n/

Thân thiện

Definition

1. Proper noun:
   • The Oligocene epoch: A major division of geologic time within the Paleogene Period, following the Eocene and preceding the Miocene. It is characterized by significant global cooling, the expansion of grasslands, and the evolution of many modern mammal families.

Usage Examples

• Proper noun:
  • The fossil record shows a major diversification of mammals during the Oligocene.
  • Scientists study rock formations from the Oligocene to understand ancient climate change.

Advanced Usage

• "Oligocene-Miocene boundary": Refers to the transition point between the Oligocene and Miocene epochs.
  • The research focuses on environmental shifts at the Oligocene-Miocene boundary.

Variants and Related Words

• Oligocene Epoch (n): The full formal name for the geologic time unit.
  • The Oligocene Epoch lasted approximately 15 million years.

Synonyms

• Geologic epoch: A general term for a subdivision of geologic time. (Note: This is a broader category, not a direct synonym for the specific epoch name "Oligocene".)

Related Terms (Not Phrasal Verbs or Idioms)

• Paleogene: The geologic period that contains the Oligocene, Paleocene, and Eocene epochs.
• Miocene: The geologic epoch immediately following the Oligocene.
• Eocene: The geologic epoch immediately preceding the Oligocene.

Học thuật

Noun

1. from 40 million to 25 million years ago; appearance of sabertoothed cats

Từ đồng nghĩa

• Oligocene
• Oligocene epoch