placeholder image to represent content

3.1.1 Evidence (Gravity, EM, density) for the structure of the earth

Quiz by Richard Campbell

Our brand new solo games combine with your quiz, on the same screen

Correct quiz answers unlock more play!

New Quizalize solo game modes
31 questions
Show answers
  • Q1
    Occurs when a small proportion, usually between 1% and 5%, of a rock melts. The liquid fraction surrounds crystals which are still solid. This reduces the rigidity of the rock and enables it to behave as a rheid.
    Partial melting
    30s
  • Q2
    The upper rigid layer of the crust and upper mantle.
    Lithosphere
    30s
  • Q3
    A non-molten solid that deforms by viscous or plastic flow, in response to applied force. Common examples include the rocks of the mantle and rock salt (halite) which, when under pressure from overlying pressure, forms salt domes which serve as hydrocarbon traps.
    Rheid
    30s
  • Q4
    Is characterised by low seismic velocities.
    Low Velocity Zone (LVZ)
    30s
  • Q5
    A layer of the mantle below the lithosphere.
    Asthenosphere
    30s
  • Q6
    An ultramafic igneous rock composed of the minerals olivine and pyroxene.
    Peridotite
    30s
  • Q7
    Measured in Gals (after Galileo). 1 Gal = acceleration of 1 cm s⁻². As variations in gravity are very small, the unit used is milligal, or mgal. The average value for gravity on Earth is 981 000 mgal, equivalent to the well-known 9.81 m s⁻².
    Gravity
    30s
  • Q8
    The theoretical state of equilibrium between Earth's lithosphere and asthenosphere such that the lithosphere 'floats' at an elevation that depends on its thickness and density. The less dense continents rise to a higher elevation than the denser ocean floor, although the pressure exerted on the underlying asthenosphere is the same.
    Isostasy
    30s
  • Q9
    The rising up of land masses that were once depressed by ice sheets.
    Isostatic rebound
    30s
  • Q10
    A process whereby one section of the lithosphere is forced down beneath another.
    Subduction
    30s
  • Q11
    A process where a cold dense section of lithosphere sinks into the mantle.
    Slab pull
    30s
  • Q12
    An area of high heat flow above a mantle plume.
    Hot spot
    30s
  • Q13
    Measured in Watts per square metre or W m⁻². As the heat loss is small, the units used are milliwatts/m² or m W m⁻².
    Thermal flux
    30s
  • Q14
    A process by which thermal energy is transferred through a medium by a fluid. It is an important process close to mid-ocean ridges where sea water is drawn down in to the crust and replaces rising hydrothermal fluids.
    Advection
    30s
  • Q15
    The process by which thermal energy is transferred by a substance (fluids or rheids) due to buoyancy differences within the substance. Hot material expands, density reduces, and the material rises, while colder, denser material sinks under the influence of gravity. Convection is more efficient than advection or conduction, and is an important process in the mantle, atmosphere, and ocean.
    Convection
    30s

Teachers give this quiz to your class