The Earth's rocky outer crust solidified billions of
years ago, soon after the Earth formed. This crust is not a solid
shell; it is broken up into huge, thick plates that drift atop the soft,
underlying mantle.
The plates are made of rock and drift all over the globe; they move both
horizontally (sideways) and vertically (up and down). Over long
periods of time, the plates also change in size as their margins are
added to, crushed together, or pushed back into the Earth's mantle. These plates are from 50 to 250 miles (80 to 400 km) thick.
Answer:
he larger the crystals and the more mafic the composition
Explanation:
Temperature at which minerals crystallize can determine the nature of composition of the rock and the crystal sizes.
- When a magma crystallizes at high temperature, the mineral grains have enough time to aggregate around a nuclei.
- This makes the sizes big.
- Mafic minerals are know to crystallize at high temperatures.
- Felsic minerals differentiate at low temperatures.
Answer:
mabe so they needed to conserve space so that they can make the most money with the land that they have?
