Answer:
the answer is (c) the US Census Bureau
Answer:
In a divergent plate boundary, two plates move away from one another. Due to this divergent movement of plates, seafloor spreading takes place in the ocean basin along the mid-oceanic ridge and rifting take place in the continental areas. Due to the stretching of the crust, the lithosphere becomes thin, and with more progressive spreading, it results in the eruption of magma at the seafloor. This magma is basaltic in nature, that reaches the surface due to the force exerted by the uprising magma forming convection cells in the mantle. This type of plate motion results in the expansion of the ocean basin and the rift valley in the continental areas forms seas and oceans with increasing time.
The rocks that are formed at the mid-oceanic ridge are the youngest as the magma cools and solidifies very rapidly here. With further moving away from this spreading center the age of the rocks increases.
The divergent plate boundaries are also responsible for the occurrence of deep-focus earthquakes, and it also leads to the formation of volcanoes in its adjacent sides.
Answer:
The color is considered dark if the rock appears as a dark gray to black (pyroxenes, the amphibole Hornblende, the mostly Ca-plagioclases near Anorthite, and Biotite mica. Density is a property that is proportional to the composition of the rock. The higher the amount of silica (felsic) the less dense the rock will be.
Explanation:
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