Year 8 Earth and Space Science: Plate Tectonics and Rocks

A comprehensive set of vocabulary flashcards covering Earth's structure, plate tectonics theory, the rock cycle, and mineral properties based on the Year 8 Earth and Space Science student outline.

Plate Tectonics

A theory explaining global patterns of geological activity, including the formation of features at divergent, convergent, and transform plate boundaries.

Minerals

The substances that rocks are composed of, which can be classified using physical properties such as colour, streak, lustre, transparency, hardness, and cleavage.

Rocks

A collection of different minerals whose properties reflect their formation and influence their use.

Ores

Useful resources that can be extracted from minerals.

Lustre

A physical property used to identify and classify minerals based on how they reflect light.

Streak

A physical property of minerals referring to the colour of the mineral in its powdered form.

Hardness Scale

A system used to classify minerals based on their resistance to being scratched.

Cleavage

A physical property used to classify minerals based on how they break along specific planes.

Crust

The outermost layer of the Earth, categorized into two types: continental and oceanic.

Lithosphere

The horizontal layer of the Earth consisting of the crust and the uppermost part of the mantle.

Asthenosphere

A layer of the Earth located below the lithosphere.

Mantle

The layer of the Earth where convection occurs, driving the motion of tectonic plates.

Density

A property representing mass per unit volume; differences in this property cause the movement of materials during convection.

Continental Drift

A hypothesis proposed by Alfred Wegener suggesting that continents move, supported by evidence like matching coastlines, fossils, and rock types.

Pangaea

The name of the ancient supercontinent proposed by Alfred Wegener in his hypothesis of continental drift.

Sea Floor Spreading

A process and mechanism provided by Harold Hess to explain the drift of continents, supported by ocean floor topography and magnetic patterns.

Convection

The transfer of heat by the movement of materials due to density differences.

Divergent Boundary

A type of tectonic plate movemement where plates move away from each other.

Convergent Boundary

A type of tectonic plate movement where plates move toward each other.

Transform Boundary

A type of tectonic plate movement where plates slide past each other.

Destructive Boundary

A plate boundary characterized by the occurrence of earthquakes and volcanic activity typically involving subduction.

Conservative Boundary

A term for a plate boundary where crust is neither created nor destroyed, often associated with transform movement.

Subduction

A geological process occurring at certain plate boundaries where one tectonic plate moves under another.

Igneous Rocks

Rocks formed from the cooling of molten material; they can be classified as intrusive or extrusive.

Sedimentary Rocks

Rocks formed through the processes of erosion, deposition, compaction, and cementation; they can be clastic, chemical, or organic.

Metamorphic Rocks

Rocks formed from existing rocks through heat and pressure, involving contact or dynamic processes.

Weathering

The process of breaking down rocks through physical or chemical means.

Erosion

The process by which soil and rock particles are worn away and moved by natural forces.

Deposition

The process in the rock cycle where sediments, soil, and rocks are added to a landform or landmass.

Compaction

A process in the formation of sedimentary rocks where layers of sediment are pressed together by the weight of overlying layers.

Cementation

A process in the rock cycle where dissolved minerals crystallize and glue particles of sediment together into one mass.

Earthquake

A geological event caused by the sudden release of energy in the Earth's crust; they are detected using SIS tasks and occur along fault lines.

Focus

The point inside the Earth where an earthquake originates.

Epicentre

The point on the Earth's surface directly above the focus of an earthquake.

Fault

A fracture or zone of fractures between two blocks of rock, often where earthquakes occur.

Volcano

A geological feature formed by the eruption of molten rock, often occurring at plate boundaries or hotspots.