Multiple choice

Consider the following statements in relations to Earth`s topmost layer:

  1. Transverse earthquake waves moves at a speed of 3.5 km/second in that layer.
  2. The specific gravity is 2.7.
  3. It is shallowest under Continents and deepest under Oceans.
  4. Abundance of magnesium. Which of the above statements are correct

  1. 1 and 2

  2. 2 and 3

  3. 3 and 4

  4. 1, 2 and 4
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In the upper crust (Sial), S-waves travel at approximately 3.5 km/s and the average specific gravity is 2.7. Statement 3 is false because the crust is thickest under continents and thinnest under oceans; statement 4 is false because the top layer is rich in aluminum (Sial), while magnesium (Sima) is dominant in the lower layer.

Keep practicing — related questions