A level Physical Geography: Tectonics Part 1

A pulling force exerted by cold, dense oceanic plate subducting under continental plate into the mantle

A technique used to understand, analyse and assess a hazard or hazards which contrast temporally and spatially

The formation of new crust due to rising magma at a divergent plate boundary

Mixture of dense hot rock, lava, ash and gas that travels extremely fast, destroying everything in its path

Risk = (Hazard x Vulnerability) / Capacity to Cope

Less hot, high viscosity, difficult gas escape, explosive eruptions

Rising magma pushes the lithosphere upwards causing it to slide down under gravity when it cools

A natural event that has the potential to threaten both life and property

VEI; A logarithmic scale that measures the magnitude of a volcanic eruption

Gases dissolved in magma

A fault that is not slipping due to frictional resistance on the fault being greater than the shear stress across it

Convection currents from the lower mantle cause plates to move due to rotational movement in the asthenosphere

Model that shows how a country might respond after a hazard event: Relief, Rehabilitation, Reconstruction

CFZ; a belt of activity following mountain ranges around the world

Strategies used to avoid, delay or prevent hazard events

Waves generated from the hypocentre, transverse, can only travel through solids, slower than P waves

Volatiles in magma released into the atmosphere after an eruption

Masses of rock, mud and water travelling down the side of a volcano

An area of seismicity corresponding with the slab being thrust downwards in a subduction zone

MMS; a logarithmic scale that measures the amount of energy released from an earthquake

The upper layers of the Earth's crust

MIS; Measures the effect on people, structures and the natural environment

Earthquakes that don't occur on a plate margin

Very hot and very slow lava streams destroying everything in its path

A hazard becoming reality in an event that causes deaths and damage to goods/property and the environment

Oceanic lithosphere is recycled into the Earth's mantle

The ability to anticipate, cope with, resist and recover from natural hazards

The lower layers of the Earth's crust

Process in which governments and other organisations work together to protect people from natural hazards

Volcanoes not located on a plate boundary; magma rises through the lithosphere and erupts to form active volcanoes

OFZ; a belt of activity along the mid-ocean ridges

A hazard generated by tectonic/geological processes

A series of larger than normal waves, usually caused by volcanic eruptions or underwater earthquakes

Very hot, low viscosity, easy gas escape, peaceful eruptions

The point at which an earthquake begins

Sudden floods caused by melted glacial snow and ice

The sum of the ways individuals and institutions, public and private, manage common affairs

DART

Waves generated from the epicentre, most destructive and slowest, travels along and focuses all its energy onto the earth's surface, can only travel through solids

Has potential to have social and economic impacts

The varying magnetism in the rocks due to the polarity of the earth switching every 300,000 years

Waves generated from the hypocentre, longitudinal, can travel though solids, liquids and gases

Gradual movement of the continents across the earth's surface over geographical time