Earth's crust is composed of iron, oxygen, silicon and magnesium. Other elements are also present in small amounts, including sulfur, nickel, copper and calcium. Earth's crust ranges from 3 to 44 miles deep, and it is almost the only source humans have for obtaining minerals.Know More
Early in its history, Earth underwent a process of differentiation. During this process, the heavy minerals suspended in the still-molten Earth sank to the core, where they remain, subjected to intense pressure and heat.
Above this layer, Earth has a mantle that extends about 1,800 miles from the outer core to just beneath the crust. Convection within this mantle layer is responsible for the movement of the Earth's crustal plates. The lighter elements that went into Earth's formation remained at or near the surface, and formed both the continental crust and the denser, heavier sea floor.
Sea floor tends to be driven under, or subducted, where it meets a continental plate, and sinks to a region just under the crust called the melt zone. Here, water contained in the rock convects heat into the block of sea floor and causes it to melt. The resulting magma is relatively light and carries minerals to the surface in volcanic eruptions.Learn more about Desserts
Iron is found throughout the earth, comprising about 32 percent of the earth's crust and up to 80 percent of the Earth's core. It is the second most abundant metal on earth.Full Answer >
The Earth's crust is composed of several minerals and elements, including iron, oxygen, silicon, magnesium, sulfur and nickel. Present in smaller amounts are calcium, aluminum and several other elements. The crust is the outermost portion of the Earth, which is comprised of three layers.Full Answer >
To make a Philadelphia Cheesecake, combine 1 ½ cups cracker crumbs, 1/3 cup melted butter and 3 tablespoons sugar to make the crust, before pouring a mixture of sugar, softened cream cheese, eggs and vanilla over the crust. Bake the cake for 55 minutes.Full Answer >
Iron can be found in the Earth's core, in the Earth's crust, in hemoglobin, in steel and in magnets. It is rare to find iron in its elemental form on Earth, but it has been found in igneous rocks in Russia.Full Answer >