Tectonic Hazards
● Name the different Tectonics
○ Plate boundaries
○ Earthquakes
○ Volcanoes
○ Tsunamis
● What is an earthquake?
An earthquake is the result of a sudden release of stored energy in the Earths crust
that creates seismic waves
● What is a volcano?
Opening in the earths crust through which magma, ash and gas erupt
● What is a Tsunami?
A series of fast-moving waves in the ocean caused by powerful earthquakes or
volcanic eruptions
● Describe the distribution of plate tectonics?
○ Usually found along plate boundaries such as Eurasian, North American and
South American
○ Some found in the middle of plate boundaries which are called intraplate
hazards
● What are the two types of crust?
Oceanic - Dense, made of basalt
Continental - Thin/ Low in density/floats on mantle
● Describe the lithosphere?
Lithosphere is the crust or the outer edge of the earth
● Describe the process of a convection current?
Heat at the core of the earth causes currents to rise when they reach near the crust
they fall back down due to no hat.
● What is the Asthenosphere?
The layer beneath the lithosphere
It is semi-molten
magma is more ductile (bends) and viscous so is thick
, ● What is the theory of slab pull?
○ As oceanic crust solidifies it becomes denser and thicker causing it to the sink
into the mantle under its own weight
● Describe the structure of the earth?
6500 km to the centre of the earths core it is believed to be over 6000 degrees
celsius meaning scientists cannot drill in to it instead they map it using evidence from
seismic waves.
● Summarise the plate tectonic theory?
the lithosphere is broken into several major and several minor parts called tectonic
parts that move relative to each other over the asthenosphere. This movement
causes earthquakes and volcanoes to erupt. Tectonic plates are large irregularly
shaped slabs of solid rock that vary in size and move slowly. (about 2 to 15 cm a
year)
● What is mantle convection causing the movement of plates?
The heat produced by the decay of radioactive elements in the earth's core creating
convection currents. These currents move in circles thus causing plates to move.
● What is slab pull in the movement of plates?
Newly formed oceanic crust at mid-oceanic ridge becomes denser and thicker as it
colls this causes it to sink into the mantle under its own weight and pull the rest of the
plate
● What is subduction in the movement of plates?
As an oceanic and continental plate move towards each other, one slides
underneath the other into the mantle where it melts in an area known as the
subduction zone.
● What is seafloor spreading in the movement of plates?
In the middle of many oceans are mid-ocean ridges or underwater mountain ranges.
These are formed when hot magma is forced up from the asthenosphere and
hardens forming a new oceanic crust. This crust pushes the tectonic plates apart in a
process called seafloor spreading.
● What happens every 400,000 years or so?
Every 400000 years or so the magnetic fields change direction causing the magnetic
South and North poles to swap. When lava cools and becomes rock, minerals inside
the rock line up with the earths magnetic direction.
● What happens when 2 tectonic plates meet?
Two tectonic plates meet
form plate boundary
each plate boundary creates distinct processes and landforms
● Name the different Tectonics
○ Plate boundaries
○ Earthquakes
○ Volcanoes
○ Tsunamis
● What is an earthquake?
An earthquake is the result of a sudden release of stored energy in the Earths crust
that creates seismic waves
● What is a volcano?
Opening in the earths crust through which magma, ash and gas erupt
● What is a Tsunami?
A series of fast-moving waves in the ocean caused by powerful earthquakes or
volcanic eruptions
● Describe the distribution of plate tectonics?
○ Usually found along plate boundaries such as Eurasian, North American and
South American
○ Some found in the middle of plate boundaries which are called intraplate
hazards
● What are the two types of crust?
Oceanic - Dense, made of basalt
Continental - Thin/ Low in density/floats on mantle
● Describe the lithosphere?
Lithosphere is the crust or the outer edge of the earth
● Describe the process of a convection current?
Heat at the core of the earth causes currents to rise when they reach near the crust
they fall back down due to no hat.
● What is the Asthenosphere?
The layer beneath the lithosphere
It is semi-molten
magma is more ductile (bends) and viscous so is thick
, ● What is the theory of slab pull?
○ As oceanic crust solidifies it becomes denser and thicker causing it to the sink
into the mantle under its own weight
● Describe the structure of the earth?
6500 km to the centre of the earths core it is believed to be over 6000 degrees
celsius meaning scientists cannot drill in to it instead they map it using evidence from
seismic waves.
● Summarise the plate tectonic theory?
the lithosphere is broken into several major and several minor parts called tectonic
parts that move relative to each other over the asthenosphere. This movement
causes earthquakes and volcanoes to erupt. Tectonic plates are large irregularly
shaped slabs of solid rock that vary in size and move slowly. (about 2 to 15 cm a
year)
● What is mantle convection causing the movement of plates?
The heat produced by the decay of radioactive elements in the earth's core creating
convection currents. These currents move in circles thus causing plates to move.
● What is slab pull in the movement of plates?
Newly formed oceanic crust at mid-oceanic ridge becomes denser and thicker as it
colls this causes it to sink into the mantle under its own weight and pull the rest of the
plate
● What is subduction in the movement of plates?
As an oceanic and continental plate move towards each other, one slides
underneath the other into the mantle where it melts in an area known as the
subduction zone.
● What is seafloor spreading in the movement of plates?
In the middle of many oceans are mid-ocean ridges or underwater mountain ranges.
These are formed when hot magma is forced up from the asthenosphere and
hardens forming a new oceanic crust. This crust pushes the tectonic plates apart in a
process called seafloor spreading.
● What happens every 400,000 years or so?
Every 400000 years or so the magnetic fields change direction causing the magnetic
South and North poles to swap. When lava cools and becomes rock, minerals inside
the rock line up with the earths magnetic direction.
● What happens when 2 tectonic plates meet?
Two tectonic plates meet
form plate boundary
each plate boundary creates distinct processes and landforms
