Earth Structure and Movement

Question 1

Why do different layers have different compositions and consistencies

Answer 1

This is due to the relative melting points of the different layers (nickel-iron core, silicate crust, and mantle) and the increase in temperature and pressure as depth increases.

Question 2

Theory of plate tectonics

Answer 2

Plate tectonics is a scientific theory that explains how major landforms are created as a result of Earth’s subterranean movements.

Question 3

Role of heat energy and convection currents that drive the movement of the plates

Answer 3

• Tremendous heat and pressure within the earth cause the hot magma to flow in convection currents
• Convection currents drive the movement of Earth’s rigid tectonic plates in the planet’s fluid molten mantle

Question 4

Fold

Answer 4

Folding occurs when tectonic processes put stress on a rock, and the rock bends, instead of breaking.

Question 5

Fault

Answer 5

• Normal (a dip-slip fault in which the block above the fault has moved downward relative to the block below)
• Reverse ( a dip-slip fault in which the upper block, above the fault plane, moves up and over the lower block)
• Strike-slip faults (a common mode of deformation in both continental and oceanic crust and occurs at a wide range of scales)