What are the three main rock types in the rock cycle?
Sedimentary, metamorphic, and igneous.
What processes drive the rock cycle?
Plate tectonics and the water cycle.
How does an igneous rock become sedimentary?
Through weathering and erosion, the rock breaks into fragments that are transported, deposited, and lithified into sedimentary rock.
What is lithification?
The process of compacting and cementing sediment into solid rock.
Name two types of sedimentary rocks based on formation. Give an example of each.
Clastic (e.g., sandstone) and biogenic (e.g., limestone from shells).
What is the difference between regional and contact metamorphism?
Regional metamorphism affects large areas due to mountain building; contact metamorphism occurs when magma heats surrounding rock.
What is foliation in metamorphic rocks?
Distinct bands of different minerals and colors caused by regional metamorphism.
How does an igneous rock form from magma?
Magma cools and crystallizes, either slowly underground (intrusive) or rapidly on the surface (extrusive).
What is the difference between intrusive and extrusive igneous rocks?
Intrusive rocks cool slowly underground, forming coarse grains (e.g., granite); extrusive rocks cool quickly on the surface, forming fine grains or glass (e.g., basalt, obsidian).
Can any rock type become magma?
Yes, any of the three main rock types can melt into magma under high temperature and pressure.
What is the Wilson cycle?
The repeated opening and closing of ocean basins due to plate tectonics, driving the rock cycle.
What is weathering?
The breakdown of rocks at Earth's surface by physical or chemical processes.
What is erosion?
The transport of weathered rock fragments by natural agents like water, wind, or ice.
What is metasomatism?
The addition of chemicals from magma to surrounding rock during contact metamorphism.
Name a fine-grained extrusive igneous rock.
Basalt.
Name a coarse-grained intrusive igneous rock.
Granite.
What is a natural glass formed by rapid cooling of lava?
Obsidian.
What is clastic sedimentary rock?
Rock formed from fragments (clasts) of other rocks, e.g., sandstone.
What is biogenic sedimentary rock?
Rock formed from the remains of living organisms, e.g., fossiliferous limestone.
What is precipitate sedimentary rock?
Rock formed by evaporation of mineral-rich water, e.g., rock salt.
What is the rock cycle?
The continuous process by which rocks transform between sedimentary, metamorphic, and igneous types over geologic time.