The correct option is 2 and 3 only.
Explanation
The evolution of the Earth's lithosphere and interior structure is driven by the processes of accretion, gravitational compression, and differentiation. These processes determined the physical state and stratification of the Earth during its primordial stage.
Statement-wise Analysis:
- Statement 1 is Incorrect: During its primordial stage, the Earth was mostly in a volatile and hot state, not a solid state. Due to high temperatures generated by accretionary collisions and radioactive decay, the planet was largely molten. This volatile state allowed materials to move and separate.
- Statement 2 is Correct: As the Earth formed, gravitational forces caused the material to compress. This compression led to a gradual increase in density towards the interior. According to the laws of thermodynamics and planetary formation, this increase in density and pressure resulted in a corresponding increase in the internal temperature.
- Statement 3 is Correct: The high temperature and semi-molten/volatile state allowed for the process of differentiation. Heavier materials (like iron and nickel) sank towards the center to form the core, while lighter, less dense materials moved towards the surface to form the crust and lithosphere. This separation was strictly dependent on the densities of the materials.
Key Takeaway:
The primordial Earth was in a volatile state, which facilitated differentiation-the separation of materials based on density, creating the Earth's layered structure (Crust, Mantle, Core).