<span>Magma that squeezes into a horizontal crack is called a sill. Magma that squeezes into a vertical crack is called a dike. Both are considered to be rock intrusions wherein magma seeps into the cracks of old sedimentary rock formations. The difference is that sills are tubular and horizontal in nature, while dikes are vertical in nature.</span>
The main form of radiation released by Earth at night is infrared radiation.
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Infrared radiation is invisible to the human eyes, but we can feel it as heat.
Answer:
Explanation:
At constructive margins such the mid oceanic ridge where new magma are brought to the surface, evidences abounds to support the theory of continental drift through paleomaganetism.
Continental drift is simply the moving of the land masses on earth from their original positions.
There are certain magnetic minerals in rocks that are able to record the prevailing magnetic conditions in a particular terrane. In a hot magma, at the oceanic ridge for example, these minerals align to the magnetic direction at work during the period when they are cooling. As new materials upwells, the cool layer shifts away from the margin each bearing the paleomagnetic record.
Therefore, through a series of reversals and normality in the magnetic direction, one can deduce that the continents actually moves.
