Here's why:

* Sedimentation: Sedimentary rocks are formed from the accumulation of sediments (like sand, mud, or organic matter) that have been transported and deposited by wind, water, or ice.

* Compaction and Cementation: Over time, these sediments are buried, compacted by the weight of overlying sediments, and cemented together by minerals dissolved in groundwater.

Examples of sedimentary rocks:

* Sandstone: Formed from sand grains

* Limestone: Formed from the shells of marine organisms

* Shale: Formed from clay

* Coal: Formed from compressed plant matter

Let me know if you have more questions about rocks!