Here's why:

* Formation: Sedimentary rocks are formed from the accumulation of sediments (like sand, mud, or shells) that are deposited in layers over time.

* Compression: The weight of the overlying layers compresses these sediments, eventually cementing them together to form rock.

* Visible Layers: The layers of sediment are often clearly visible in sedimentary rocks, creating a layered or banded appearance.

Examples of sedimentary rocks with visible layers include:

* Sandstone: Formed from sand grains

* Shale: Formed from clay

* Limestone: Formed from the remains of marine organisms

Let me know if you'd like to learn more about sedimentary rocks!