Geothermal Energy
, Geothermal Gradient
• We know that the interior of the Earth is hot because volcanoes
erupt molten lava and the temperature in boreholes and deep mines
increasing with depth. The highest temperatures are in the core but
the mantle stores the greatest amount of heat energy because
silicates are poor conductors of heat.
• The rate of increase in temperature per unit depth in the Earth due
to the outflow of heat from the centre is called geothermal gradient.
• The gradient is measured by taking the temperature of rocks at the
top and bottom of boreholes. In most parts of the world, the gradient
near the surface is 25°C/km.
• More advanced indirect techniques include electromagnetic surveys
and seismic tomography.
, Geothermal Gradient
, Geothermal Gradient
• We know that the interior of the Earth is hot because volcanoes
erupt molten lava and the temperature in boreholes and deep mines
increasing with depth. The highest temperatures are in the core but
the mantle stores the greatest amount of heat energy because
silicates are poor conductors of heat.
• The rate of increase in temperature per unit depth in the Earth due
to the outflow of heat from the centre is called geothermal gradient.
• The gradient is measured by taking the temperature of rocks at the
top and bottom of boreholes. In most parts of the world, the gradient
near the surface is 25°C/km.
• More advanced indirect techniques include electromagnetic surveys
and seismic tomography.
, Geothermal Gradient
