1. Crust:
* Composition: Primarily composed of igneous, sedimentary, and metamorphic rocks, mainly composed of oxygen, silicon, aluminum, iron, calcium, sodium, potassium, and magnesium.
* Thickness: Varies from 3-5 km (2-3 miles) under oceans (oceanic crust) to 30-70 km (19-43 miles) under continents (continental crust).
2. Mantle:
* Composition: Solid rock, mostly composed of silicate minerals like olivine and pyroxene, with smaller amounts of iron, calcium, aluminum, and magnesium.
* Thickness: About 2,900 km (1,800 miles) thick.
3. Outer Core:
* Composition: Liquid iron and nickel with small amounts of sulfur, silicon, and oxygen.
* Thickness: About 2,200 km (1,400 miles) thick.
4. Inner Core:
* Composition: Solid iron and nickel.
* Thickness: About 1,220 km (758 miles) thick.
Other Components:
* Atmosphere: Primarily composed of nitrogen (78%), oxygen (21%), and argon (1%), along with trace amounts of other gases.
* Hydrosphere: Includes all water on Earth, including oceans, lakes, rivers, groundwater, and ice.
* Biosphere: The sum of all life on Earth, including plants, animals, fungi, and microorganisms.
Overall Composition:
* Iron (Fe): 32.1%
* Oxygen (O): 30.1%
* Silicon (Si): 15.1%
* Magnesium (Mg): 13.0%
* Sulfur (S): 2.9%
* Nickel (Ni): 1.8%
* Calcium (Ca): 1.5%
* Aluminum (Al): 1.4%
It's important to note that this composition is based on the Earth's mass, and the proportions may vary slightly depending on the specific layer or region. The composition of Earth is constantly evolving through geological processes like plate tectonics, volcanic eruptions, and weathering.
