LAYERS OF THE EARTH The Earth is made up of several distinct layers, each with unique composition, properties, and functions. These layers can be classified into chemical layers (based on composition) and physical layers (based on mechanical properties). 1. CRUST Definition: The outermost solid layer of the Earth where we live. Types: Continental Crust – Thick (30–70 km), less dense, mainly granite rocks. Oceanic Crust – Thin (5–10 km), denser, mainly basalt rocks. Characteristics: Relatively co