GEO 3 - PLATE TECTONICS

Lithosphere

Rigid outer layer of Earth, includes crust and upper mantle.

Asthenosphere

Ductile, semi-fluid layer beneath the lithosphere.

Alfred Wegener

A German scientist who proposed the theory of continental drift

Continental Drift

Theory proposing continents moved across Earth's surface over time.

Pangaea

Supercontinent that existed before breaking apart 200 million years ago.

Tectonic Cycle

Processes that build and break down the lithosphere.

Heat Flow

Measurement of heat from Earth's interior, indicating crust formation.

Rock Formations

Similarities in rocks across continents supporting continental drift.

Mid-Ocean Ridges

Underwater mountain ranges where new crust is formed.

Old Oceanic Crust

Crust that cools and moves away from mid-ocean ridges.

Thermal Structure

Temperature distribution within Earth's interior affecting tectonic activity.

Ocean Drilling

Method for obtaining samples from ocean floor.

Plate Boundaries

Edges where two tectonic plates meet.

Divergent Boundaries

Plates move apart, forming new oceanic crust.

Convergent Boundaries

Plates collide, causing subduction or continental collision.

Transform Boundaries

Plates slide past each other, causing earthquakes.

Mesosaurus

Freshwater reptile fossil found in South America and Africa.

Glossopteris

Plant fossil found in India, Antarctica, Australia.

Appalachian Mountains

Similar to Caledonian Mountains in Scotland and Scandinavia.

Pacific Ring of Fire

Region with frequent earthquakes and volcanic activity.

Paleomagnetism

Study of Earth's magnetic field recorded in rocks.

Mantle Convection

Churning motion in Earth's mantle driving plate movement.

Harry Hess

Proposed seafloor spreading theory in the 1960s.

Seafloor Spreading

Process of new oceanic crust formation at ridges.

Divergent Boundaries/Constructive Boundaries

Tectonic plates moving apart, forming new crust.

Oceanic-Continental Convergence

Oceanic plate subducts beneath continental plate, forming trenches.

Oceanic-Oceanic Convergence

Subduction of one oceanic plate beneath another, forming island arcs.

Continental-Continental Convergence

Two continental plates collide, creating mountain ranges.

Subduction zones

regions where one tectonic plate is forced beneath another, leading to the recycling of oceanic crust into the mantle

Mid-Atlantic Ridge

Example of a divergent boundary between two plates.

Mariana Islands

Example of oceanic-continental subduction boundary.

Himalayas

Mountain range formed by Indian and Eurasian Plate collision.

Subduction Zones

Regions where one plate is forced beneath another.

San Andreas Fault

Famous transform boundary in California.

Transform faults

faults that accommodate horizontal movement between tectonic plates

Plate Movement Rate

Speed at which tectonic plates shift.

Pacific Plate

Moves at approximately 10 cm/year.

Eurasian Plate

Moves at about 2 cm/year.

Geological Hazards

Natural disasters like earthquakes and eruptions.

Slab Pull

Force from a sinking plate during subduction.

Ocean Trench

Deep depression formed at subduction zones.

Hotspots

Volcanic areas not linked to plate boundaries.

Mantle Plumes

Columns of hot rock rising from the mantle.

Slab pull

e force exerted by a sinking plate as it subducts into the mantle.

Ridge push

force exerted by rising magma at mid-ocean ridges, which pushes tectonic plates apart.

Rock Cycle

Continuous process of rock formation and transformation.

Igneous Rocks

Formed from cooling and solidification of magma.

Sedimentary Rocks

Created from compacted sediments over time.

Metamorphic Rocks

Transformed from sedimentary or igneous rocks under pressure.

Volcanism

Process of magma reaching Earth's surface.

Erosion

Breaking down rocks into smaller particles.

Sedimentation

Accumulation and compaction of sediments into rocks.

Subduction

Oceanic plate forced beneath another plate.

Subduction and melting

processes that recycle oceanic crust back into the mantle, playing a crucial role in the rock cycle.