The correct option is 2 only
Explanation
Deposition is an exogenic geomorphic process that occurs when the agents of erosion (such as running water, wind, or glaciers) lose their kinetic energy and can no longer transport the load they are carrying. It is the settling of sediments transported by these agents.
Statement-wise Analysis:
- Statement 1 is Incorrect: Deposition is technically a consequence of erosion rather than an independent or distinct work of an agent. Erosion involves the acquisition and transportation of rock debris. When the erosional agents lose their velocity and energy, the materials they carry begin to settle. Therefore, deposition is the result of the cessation of the transport process initiated by erosion.
- Statement 2 is Correct: Deposition occurs when erosional agents lose velocity, not when they gain it. A gain in velocity increases the kinetic energy of the agent, enhancing its capacity to erode and transport material. Conversely, a reduction in velocity on gentler slopes or due to obstructions leads to the settling of sediments.
- Statement 3 is Incorrect: The sorting of materials during deposition follows the principle of carrying capacity relative to particle size and weight. Coarser and heavier materials get deposited first as the velocity decreases because they require more energy to remain in suspension or motion. Finer materials (such as silt and clay) are deposited later, as they can be transported even at lower velocities.
Key Takeaway:
Deposition is the settling of sediments caused by a loss of kinetic energy in geomorphic agents. During this process, coarser materials settle first, followed by finer materials (sorting), making it a direct consequence of the erosional cycle.