Table of Contents
- 1 What causes the plates of the crust to move?
- 2 How does the convection in the mantle affect the crust above it?
- 3 How do convection currents cause plates to move?
- 4 How do convection currents affect the crust?
- 5 How does convection current affect plate tectonics?
- 6 How mantle convection causes plate motion?
- 7 What happens when convection currents reach the mantel?
- 8 What happens when tectonic plates move in the mantle?
What causes the plates of the crust to move?
Earth’s crust, called the lithosphere, consists of 15 to 20 moving tectonic plates. The heat from radioactive processes within the planet’s interior causes the plates to move, sometimes toward and sometimes away from each other. This movement is called plate motion, or tectonic shift.
What happens when convection currents occur in the mantle?
Explanation: Convection currents within the Earth’s mantle are caused by hot material rising upwards, cooling, then dropping back toward the core. If the interior of the Earth were to cool enough for convection currents to stop, then the motion of the plates would cease, and the Earth would become geologically dead.
How does the convection in the mantle affect the crust above it?
The core heats up the magma and causes a convection current. When magma comes to the top of the mantle, it pushes against tectonic plates, which are huge slabs of rock which the crust rests on.
How does convection work in the mantle?
The mantle is heated from below (the core), and in areas that are hotter it rises upwards (it is buoyant), whereas in areas that are cooler it sink down. This results in convection cells in the mantle, and produces horizontal motion of mantle material close to the Earth surface.
How do convection currents cause plates to move?
Convection currents describe the rising, spread, and sinking of gas, liquid, or molten material caused by the application of heat. Tremendous heat and pressure within the earth cause the hot magma to flow in convection currents. These currents cause the movement of the tectonic plates that make up the earth’s crust.
In what part of the mantle does convection current occur?
Convection currents are identified in Earth’s mantle. Heated mantle material is shown rising from deep inside the mantle, while cooler mantle material sinks, creating a convection current. It is thought that this type of current is responsible for the movements of the plates of Earth’s crust.
How do convection currents affect the crust?
What causes mantle convection?
The primary sources of thermal energy for mantle convection are three: (1) internal heating due to the decay of the radioactive isotopes of uranium, thorium, and potassium; (2) the long-term secular cooling of the earth; and (3) heat from the core.
How does convection current affect plate tectonics?
The convection currents move the plates. Where convection currents diverge near the Earth’s crust, plates move apart. Where convection currents converge, plates move towards each other. The movement of the plates, and the activity inside the Earth, is called plate tectonics .
What is convection current in the mantle?
Convection currents are the movement of fluid as a result of differential heating or convection. In the case of the Earth, convection currents refer to the motion of molten rock in the mantle as radioactive decay heats up magma, causing it to rise and driving the global-scale flow of magma.
How mantle convection causes plate motion?
Geologists have hypothesized that the movement of tectonic plates is related to convection currents in the earth’s mantle. Tremendous heat and pressure within the earth cause the hot magma to flow in convection currents. These currents cause the movement of the tectonic plates that make up the earth’s crust.
Why does convection happen in the mantle?
Mantle convection occurs because relatively hot rocks are less dense and rise in a gravitational field while relatively cold rocks are more dense and sink. The rise of hot rocks advects heat upward while the fall of cold rocks advects cold downward; this counterflow is equivalent to an upward heat flux.
What happens when convection currents reach the mantel?
As convection currents reach the mantel, the heat causes a collision between the continental plate and the oceanic plate under water. The convection current continues to push the heated magma past the mantel level, reaching the crust of the Earth’s surface and producing a lava spout.
How does convection currents cause the Earth’s crust to move?
The Earth’s crust is broken up into pieces called plates. The crust moves because of movements deep inside the earth. Heat rising and falling inside the mantle creates convection currents generated by radioactive decay in the core. Plate tectonics cause earthquakes and volcanoes.
What happens when tectonic plates move in the mantle?
The movement of the plates can lead to volcanic eruptions, earthquakes, tsunamis and mountain-range formation. However, it does take a huge amount of movement in the mantle to move literally the heaviest rocks on Earth, so it’s a very slow process, even if the consequences – volcanic eruptions, for example – seem very quick.
How do convection currents affect a heat source?
Convection currents happen in fluids with a heat source. Hot liquid or gas near the heat source becomes hotter and less dense, so moves upwards. This forces the cooler stuff at the top to move back down. As the hot molecules move up, they cool down and begin to drop. As the cool molecules move down, they heat up and begin to rise.