Q. Consider the following differences between Sial layer and Sima layer:

1. Sial layer is less dense than the Sima layer
2. While “sial” is mainly concentrated in continental crust, “sima” is concentrated in oceanic crust

Which of the above statements is/are correct?
Answer: Both 1 & 2
Notes: Sial means Silicon and Aluminium; it has a lighter density than the Sima (Silicon and Magnesium layer). Sial is lighter than Sima due to increased amount of aluminium, and decreased amount of iron and magnesium in it.

This question is part of UPSC Daily 20 MCQ Series Course on GKToday Android app.