Definition

Noun: * Plutonic rock: A large mass of intrusive igneous rock that has solidified from magma deep beneath the Earth's surface, typically characterized by a coarse-grained or phaneritic texture due to slow cooling. It is the primary constituent of the continental crust.

Usage

The term "plutonic rock" is used in geology to classify and describe igneous rocks formed by the slow crystallization of magma within the Earth's crust. It is a formal, scientific term. * Granite is a common example of a plutonic rock. * Geologists study plutonic rocks to understand the history of mountain building.

Examples

• The mountain's core is composed of ancient plutonic rock.
• Plutonic rocks, such as gabbro and diorite, are exposed at the surface only after extensive erosion removes the overlying material.
• The slow cooling process allows large crystals to form in plutonic rock.

Advanced Usage

• Plutonic (adjective): Describes processes, features, or rocks related to or characteristic of formation at great depth. For example, "plutonic activity" or "a plutonic complex."
• The term originates from , the Roman god of the underworld, reflecting the rock's deep-seated origin.

Variants and Related Words

• Intrusive rock: A direct synonym for plutonic rock, emphasizing its formation by intruding into pre-existing rock.
• Abyssal rock: An older, less common synonym also referring to deep-seated formation.
• Batholith: A very large mass of plutonic rock, often forming the core of a mountain range.
• Pluton: A general term for any body of plutonic rock.

Synonyms

• Intrusive rock
• Abyssal rock (archaic)

Antonyms

• Volcanic rock (or extrusive rock): Igneous rock that forms from lava cooling rapidly on the Earth's surface (e.g., basalt, obsidian).

Related Phrases/Concepts

• Igneous rock: The broader category of rock formed from the cooling and solidification of magma or lava. Plutonic rock is a sub-type.
• Phaneritic texture: The coarse-grained texture typical of plutonic rocks, where individual crystals are visible to the naked eye.
• Plutonism: The geologic theory that rocks were formed by solidification from a molten state, particularly emphasizing deep-seated processes.

Noun

1. large mass of intrusive igneous rock believed to have solidified deep within the earth