* Shape:
* Angular rocks: Indicate short-distance transport, likely by gravity (rockfalls, landslides) or glaciers (glacial erosion).
* Rounded rocks: Indicate long-distance transport, usually by water (rivers, streams) or wind (sandblasting).
* Flattened rocks: May indicate transport by wind or water where there's a strong current.
* Surface texture:
* Smooth, polished surface: Suggests long-distance transport by water or wind, which cause abrasion and smoothing.
* Scratched, striated surface: Strongly indicates glacial erosion, as glaciers carry large rocks that carve grooves in the bedrock.
* Rough, angular surface: Often found in rocks transported by gravity or glaciers.
Other factors to consider:
* Rock type: Some rock types are more resistant to erosion than others.
* Presence of other erosional features: For example, if the rock has a striated surface and is found near glacial valleys, it's likely to be glacial in origin.
In conclusion, by analyzing the shape and surface texture of a transported rock, you can gain valuable insights into the forces that moved it, helping you determine the agent of erosion.
