Lecture Notes: Basic Terms, Plate Boundaries, and Continental Drift

Vocabulary flashcards covering basic terms related to Earth's structure, plate tectonics, disasters, and continental drift.

Flora

Plants.

Fauna

Animals.

Oceanic crust

Thinner but denser than continental crust.

Earth's crust thickness

Thickest under mountain regions.

Oceanic crust density vs continental crust

Oceanic crust is denser than continental crust.

Earthquake epicenters

Locations on the surface directly above the quake focus; they align with plate boundaries.

Volcanoes

Landforms that form where plates meet; not randomly scattered.

Earthquakes

Seismic events that recur in the same locations (fault zones/boundaries).

Mountains

Landforms often formed near volcanoes due to plate tectonics.

Plate boundaries

Edges where tectonic plates interact; earthquakes can occur at convergent, divergent, and transform boundaries.

Disaster preparedness

Communities should be in safe locations and have effective disaster plans.

Drop, Cover, Hold

Basic earthquake safety technique.

Convergent boundary

Plates move toward each other.

Convergent boundary example

North American Plate and Eurasian Plate.

Continental-continental convergence

Forms mountain ranges.

Oceanic-oceanic convergence

Forms volcanic islands.

Subduction

One plate sinks beneath another, often creating volcanoes and tsunamis.

Trench

Deep depression at subduction zones.

Plate collision

Plates colliding leads to mountain building.

Himalayas

Mountains formed by continental-continental convergence.

Uplift

Vertical elevation of land due to continental-continental convergence.

Subducting plate melts

Subducting plate melts as it sinks, forming magma.

Plate Y

The sinking plate in a subduction zone.

Rift Valley

Valley formed when plates move apart (divergent boundary).

Divergent boundary

Plates pulled apart; crust becomes thinner.

Seafloor spreading

Divergent process that creates new oceanic crust.

Mid-ocean ridge

Underwater mountain range formed by divergent plates.

Rift valleys

Valleys formed at divergent boundaries.

Subduction volcanism

Volcano formation driven by subduction.

Transform boundary

Plates slide horizontally past one another.

Transform faults

Faults at transform boundaries that cause earthquakes.

Slab pull

Subducting slab drags the plate downward; a driving force for plate movement.

Ridge push

Gravitational force at mid-ocean ridges that pushes plates apart.

Mantle convection currents

Movement of mantle material; hot material rises, cool sinks, driving plate motion.

Trench formation

Deep trenches form at convergent boundaries with subduction.

Driving force of plate tectonics

Mantle convection currents are the main force moving the plates.

Pangaea

The supercontinent that once contained all Earth's landmasses.

South America and Africa connected

They were part of the same landmass in Pangaea.

Continental Drift Theory

Wegener's proposal that continents move over time (1919).

Cynognathus

Fossil found in both South America and Africa, supporting Pangaea.