Earth layers (Sial vs. Sima): The heavier silicates called “Sima” (silica + magnesium) are most abundant in which part of Earth? Think of basaltic composition and oceanic crust distribution. Choose the correct option.
General Knowledge
World Geography
Difficulty: Easy
Choose an option
-
ACrust
-
BCore
-
CMantle
-
DOcean floors
Answer
Correct Answer: Ocean floors
Explanation
Given data
- Identify where silica–magnesium (sima) materials dominate.
Concept/ApproachIn classical physiography, sial (Si + Al) characterizes continental upper crust (granitic), whereas sima (Si + Mg), akin to basaltic composition, dominates the oceanic crust forming the ocean floors. The mantle is ultramafic (peridotitic) and not what is meant by sima in this context.
Final AnswerOcean floors