Georesources and Geohazards Flashcards
Name 5 geohazards.
Earthquakes, tsunamis, volcanic eruptions, landslides, sinkholes
What is another word for the centre of an earthquake?
The hypocentre
What type of wave is created first by an earthquake? What comes after?
P waves, then S waves, then surface waves
Which waves from an earthquake cause the damage?
Surface waves
What are tsunamis usually caused by?
Earthquakes
How do tsunamis form?
Large, wide waves are created at sea but as the sea gets shallower close to shore, the wavelength decreases and their amplitude increases
Name some harmful gases that can be released by a volcano.
Carbon dioxide, hydrogen chloride, hydrogen fluoride, hydrogen sulphide, sulphur dioxide
What are the distinguishing features between Basaltic and Rhyolitic lava?
Basaltic lava = runny and predictable
Rhyolitic lava = sticky and explosive
How can old fossil fuel infrastructure be used for sustainable aims?
- Geothermal energy can be produced by heating water in disused mine shafts.
- Carbon captured can be stored back into depleted coal seams/gas beds
Where do oil and gas come from?
Formed under the sea from compressed animals - usually plankton
How is coal formed?
Fossilised plants, especially from peat swamps in tropical regions
What is the process of fracking?
Water and grit/chemicals is pumped into the ground to fracture rocks and release gas.
What makes a region susceptible to sinkholes?
Soluble rocks (limestone, evaporites etc) and flowing water
What are some things that can cause landslides?
Water and erosion processes
Steepness of slope
Rock type / grain shape
Jointing and orientation of bedding planes / Arrangement of the rock layers
Weathering processes
Vegetation
Flooding
Volcanoes & earthquake activity
Human activity: mining, traffic vibrations or urbanisation
