Question

Prompt

Answer 1

Answer:

The theory of plate tectonics is based on the movement of the tectonic plates by the convection currents, and this has led to the constant change of the physical landscape on Earth.

Explanation:

The theory of plate tectonics suggests that Earth's crust is divided into numerous pieces, called tectonic plates, and they are constantly moving because of the convection currents in the mantle. The convection currents are actually the ones responsible from break up the crust, and they are a circular movement in the mantle, where the cooler and denser material drops down, while the hotter and less dense material is pushed up and creates huge pressure on the crust.

Because of the pressure of the convection currents, the tectonic plates are in constant motion in a certain direction, creating three different types of plate boundaries, convergent, divergent, and transform plate boundaries. The different interactions between the plates have led to the creation or destruction of all sorts of landforms, from mountains and volcanoes, plateaus and valleys, lakes, and ocean basins... The movement of the plates throughout the geological past has led to the formation of supercontinents where the vast majority of Earth's crust has been connected, but also to breaking apart of them and continents scattered around the globe far away from each other.

Answer 2

Answer: Each tectonic plate is free-floating and can move independently. Earthquakes and volcanoes are the direct result of the movement of tectonic plates at fault lines. The term fault is used to describe the boundary between tectonic plates. Most of the earthquakes and volcanoes around the Pacific ocean basin—a pattern known as the “ring of fire”—are due to the movement of tectonic plates in this region. Other observable results of short-term plate movement include the gradual widening of the Great Rift lakes in eastern Africa and the rising of the Himalayan Mountain range. The motion of plates can be described in four general patterns:

Collision: when two continental plates are shoved together

Subduction: when one plate plunges beneath another (Fig. 7.15)

Spreading: when two plates are pushed apart

Transform faulting: when two plates slide past each other

The rise of the Himalayan Mountain range is due to an ongoing collision of the Indian plate with the Eurasian plate. Earthquakes in California are due to transform fault motion.

Geologists have hypothesized that the movement of tectonic plates is related to convection currents in the earth’s mantle. Convection currents describe the rising, spread, and sinking of gas, liquid, or molten material caused by the application of heat. An example of convection current is shown in Fig. 7.16. Inside a beaker, hot water rises at the point where heat is applied. The hot water moves to the surface, then spreads out and cools. Cooler water sinks to the bottom.