Iliac crest pain is not that common in the general population, but it is frequent in older individuals, runners (and athletes in general), lower back pain sufferersâ¦ But that doesn`t mean âregularâ people like you and me can`t experience it from time to time!
The mantle is composed of iron-magnesium silicates, and the crust is composed of roughly 5 percent iron. All together, iron makes up an estimated 35 percent of the Earth's mass. Oxygen. Oxygen, the second most abundant element on Earth, is found mainly in the crust.
Sitting on top of the outer core, we find the mantle. This layer is by far the thickest layer of Earth, about 1,800 miles thick! It also makes up about 85% of Earth's volume. Like the core, the mantle contains mostly iron, but in the form of silicate rocks.You might be surprised to learn that this rock actually moves like a fluid, similar to how silly putty moves.arth can be divided into three main layers: the core, the mantle and the crust. Each of these layers can be further divided into two parts: the inner and outer core, the upper and lower mantle and the continental and oceanic crust. Both the inner and outer core are made up of mostly iron and a little bit of nickel.