Erosion and deposition are natural processes that shape the Earth's surface over time. These processes are driven by various agents, including water, wind, ice, and gravity. Each agent has unique characteristics and mechanisms that contribute to the reshaping of the Earth's surface.

Water Erosion:
- Rivers and streams: flowing water erodes the land by picking up and carrying away sediment.
- Waterfalls and rapids: fast-moving water erodes the land more rapidly, creating steep cliffs and canyons.
- Ocean waves: waves crashing against the shore can erode cliffs and create beaches.

Wind Erosion:
- Wind-blown particles: wind can pick up and transport small particles, such as sand and dust, causing erosion.
- Sand dunes: wind deposits sand in certain areas, forming dunes that can change shape and size over time.

Ice Erosion:
- Glaciers: large bodies of ice slowly move downhill, scraping and eroding the land beneath them.
- Moraines: piles of debris left behind by glaciers can alter the landscape.

Gravity Erosion:
- Mass wasting: gravity causes rocks and soil to move downhill, leading to processes like landslides and rockfalls.

Deposition:
- Sediment transport: agents of erosion carry sediment from one location to another.
- Sediment deposition: when the energy of the agent decreases, it drops the sediment it was carrying.
- Deltas: rivers deposit sediment at their mouths, forming delta landforms.
- Alluvial fans: sediment deposited by rivers spreads out in a fan-shaped pattern.

Impact on Earth's Surface:
- Formation of valleys, canyons, and gorges through the erosion of rock and soil.
- Creation of coastal features such as cliffs, beaches, and barrier islands through the action of waves and currents.
- Development of sand dunes in deserts and coastal areas due to wind erosion and deposition.
- Shaping of mountains and mountain ranges through glacial erosion and the deposition of moraines.
- Alteration of landscapes through mass wasting events like landslides and rockfalls.
- Formation of fertile plains and river deltas through deposition of sediment.

Overall, the agents of erosion and deposition play a crucial role in shaping the Earth's surface by gradually wearing down high points and depositing sediment in lower areas. These ongoing processes contribute to the dynamic nature of the Earth's landscape, constantly reshaping it over time.