Topic 1 - Hazardous Earth Flashcards
(108 cards)
Define after shocks
aftershocks follow an earthquake as the fault ‘settles’ into its new position
What is Andesitic Lava?
a thick and sticky lava erupted from composite volcanoes
What is the asthenosphere?
Part of the Earths’ mantle. It is a hot, semi-molten layer that lies beneath the tectonic plates
What are base isolators?
flexible pads on which a building is built to help it withstand earthquakes by isolating it from the moving ground
Define Basaltic lava
lava that is low in silica, fluid that flows easily
What is the collision zone?
where two tectonic plates collide – forming mountains like the Himalayas
What is a composite volcano?
a steep-sided volcano that is made up of a variety of materials, such as lava and ash
Define a conservative plate boundary
where two plates are sliding alongside each other
What is continental crust?
thick crust forming the Earth’s land masses
What are convection currents?
circular current of heat in the mantle
What happens at a convergent plate boundary?
where two plates are moving towards each other, resulting in one plate sinking beneath the other
Define the core of the earth
the central part of the Earth’s structure, made up of a solid inner and a liquid outer core
What is the Coriolis effect?
the deflection of air movement by the Earth’s rotation
Define the term crater
a depression in the ground formed by volcanic activity, often circular in shape with steep sides
What is cross-bracing on a building?
a system of supports built diagonally inside buildings to help them withstand earthquakes
Define the crust
the outer layer of the Earth
Describe a cumulonimbus cloud
very tall, dense clouds that often bring heavy rain, thunder and lightning
Define a divergent plate boundary
where two plates are moving apart
Define an earthquake
a sudden and often violent shift in the rocks forming the Earth’s crust, which is felt at the surface
Define the term effusive
a type of eruption where runny lava flows steadily out of a fissure or vent
Define the epicentre
the point at the Earth’s surface directly above an earthquake’s focus
Define an escarpment
a continuous line of steep slopes above a gentle dip slope caused by the erosion of alternate strata
What does the term ‘eye’ mean in a tropical storm
the centre of a tropical cyclone; an area of clear conditions created by air converging at the centre of the storm and then sinking
What is the eye wall
a thick bank of cloud around the eye with high wind speeds and heavy rain