Geology and Rock Types in Washington and the U.S.

Igneous Rocks

Formed from cooling magma; includes basalt, andesite.

Sedimentary Rocks

Formed from sediment compaction; includes sandstone, shale.

Metamorphic Rocks

Altered rocks due to heat and pressure; includes schist.

Rock Cycle

Continuous process of rock formation and transformation.

Lithosphere

Earth's rigid outer layer involved in rock formation.

Hydrosphere

Water's role in sediment transport and weathering.

Atmosphere

Influences weathering and erosion through climate conditions.

Biosphere

Organic processes contribute to sedimentary rock formation.

Divergent Boundaries

Magma rises and cools, forming basaltic rocks.

Convergent Boundaries

Partial melting creates andesite and granite rocks.

Transform Boundaries

No new rock formation; can cause metamorphism.

Hotspot Volcanoes

Basalt and rhyolite formed from mantle plumes.

Partial Melting

Only part of a rock melts, altering composition.

Basaltic Magma

Low silica magma from mantle partial melting.

Andesitic Magma

Intermediate silica magma from oceanic crust melting.

Rhyolitic Magma

High silica magma from continental crust melting.

Volcanic Rocks

Formed from rapid lava cooling; e.g., basalt.

Plutonic Rocks

Formed from slow magma cooling; e.g., granite.

Clastic Sedimentary Rocks

Formed from compacted rock fragments; e.g., sandstone.

Biochemical Sedimentary Rocks

Accumulation of organic materials; e.g., limestone.

Chemical Sedimentary Rocks

Precipitation of minerals from water; e.g., gypsum.

Contact Metamorphism

Localized heating from nearby molten magma.

Regional Metamorphism

Widespread metamorphism from intense pressure and heat.

Active Gold Mining Regions

States like California and Nevada have significant gold mining.

Hydrothermal Activity

Magma heats groundwater, forming mineral-rich solutions.

Connection to Magma

Magma drives hydrothermal systems and mineral deposits.