EARTH SCIENCE
TECTONICS
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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gravity.
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Earth’s magnetic field.
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convection currents in the asthenosphere.
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subduction.
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Detailed explanation-1: -Answer: 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.
Detailed explanation-2: -The plates move on a hot flowing mantle layer called the asthenosphere, which is several hundred kilometers thick. Heat within the asthenosphere creates convection currents (similar to the currents that can be seen in the lava lamp).
Detailed explanation-3: -Magma is the molten rock below the crust, in the 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.
Detailed explanation-4: -The hypothesis of convection currents suggests that flow in the mantle is induced by currents which drag and move the lithospheric plates above the asthenosphere. Convection currents rise and spread below divergent plate boundaries and converge and descend along convergent.
Detailed explanation-5: -Heat from the core makes magma in the mantle rise towards the crust. As the hot current nears the crust, it begins to cool and sink back towards the core. As the magma sinks, it drags the plates across the surface of the Earth. The movement of the plates, and the activity inside the Earth, is called plate tectonics .