Question

Earth's tectonic plates are constantly in motion, shaping the planet's surface. Select the factors associated with the movement of tectonic plates:

1. Convection currents in the mantle
2. Gravitational forces
3. Earth's magnetic field
4. Volcanic eruptions

• A. iii, iv
• B. None of these
• C. i, ii, iv
• D. i only

Answer 1

Answer:

C. i, ii, iv

Earth's Tectonic Plates

• Tectonic plates are pieces of Earth's crust and uppermost mantle, together referred to as the lithosphere. 
• They cover the entire surface of the Earth and are responsible for shaping the planet's surface through various geological processes.
• Tectonic plates interact with each other at their boundaries, where geological activity is most pronounced.

Role of Convection currents

• Convection currents in the mantle are a significant factor driving the movement of tectonic plates.
• Heat from the Earth's interior causes material in the mantle to become less dense and rise, creating convection currents.
• These currents exert forces on the overlying tectonic plates, causing them to move.

Gravitational forces

• Gravitational forces play a crucial role in plate tectonics.
• The weight of tectonic plates and the gravitational pull of the Earth cause plates to sink into the mantle at subduction zones and to move away from mid-ocean ridges.

Volcanic eruptions

• Volcanic eruptions are associated with plate tectonics, particularly at convergent boundaries.
• When tectonic plates collide or move apart, it can lead to the formation of volcanoes and volcanic activity.