1. Transport:
* Erosion: Gravity initiates erosion by pulling materials downhill. This can happen through processes like landslides, rockfalls, and soil creep.
* Transportation: Gravity acts as a driving force for various transportation mechanisms:
* Water: Gravity pulls water downhill, creating rivers and streams that carry sediments. The stronger the flow, the larger the particles the water can transport.
* Wind: Gravity contributes to the creation of wind patterns and the movement of air. Wind can pick up and transport fine sediments like sand and dust.
* Ice: Gravity pulls glaciers downhill, causing them to scrape and erode the land, picking up and transporting rocks and sediment.
2. Deposition:
* Decreased Velocity: As transporting agents like water, wind, or ice lose velocity, their ability to carry sediment decreases. Gravity contributes to this loss of velocity as:
* Water: Water slows down as it enters a wider channel, a lake, or the ocean.
* Wind: Wind slows down as it encounters obstacles or reaches a calmer area.
* Ice: Glaciers slow down as they reach flatter terrain or warmer temperatures.
* Sediment Settling: When the transporting agent loses its velocity, gravity causes the sediments to settle out and accumulate. Heavier sediments settle first, followed by lighter ones.
Specific Examples:
* River Deltas: Rivers carry sediment to the sea, where the water slows down, and gravity causes the sediment to settle, creating deltas.
* Sand Dunes: Wind carries sand grains, and gravity causes them to deposit in sheltered areas, forming sand dunes.
* Glacial Moraines: Glaciers transport rocks and sediment, and as they melt, gravity causes the material to deposit at the glacier's edge, creating moraines.
Overall: Gravity is the fundamental force behind deposition. It initiates erosion, drives transportation mechanisms, and causes the final settling of sediments, shaping landforms and influencing the distribution of Earth's materials.
