The Earth's crust is primarily composed of eight elements.
The vast majority (98.4%) of the Earth's crust is composed of just eight elements. These elements, listed below with their approximate weight percentages, are the building blocks of the rocks and minerals that make up the crust:
- Oxygen (O): ~46.6%
- Silicon (Si): ~27.7%
- Aluminum (Al): ~8.1%
- Iron (Fe): ~5.0%
- Calcium (Ca): ~3.6%
- Sodium (Na): ~2.8%
- Potassium (K): ~2.6%
- Magnesium (Mg): ~2.1%
All other elements comprise the remaining 1.6% of the crust's composition. These include elements like titanium, hydrogen, phosphorus, manganese, sulfur, carbon, and many trace elements.
It's important to note that the exact composition can vary slightly depending on the location (continental vs. oceanic crust). However, the eight elements listed above consistently dominate the crustal composition. The crust is rich in oxygen and silicon because these are the fundamental components of silicate minerals, which are the most abundant minerals found in the Earth's crust. The prevalence of aluminum, iron, calcium, sodium, potassium, and magnesium also reflects the importance of aluminosilicate minerals in the crust's makeup.
