Are clastic rocks sedimentary?

Yes. Clastic rocks are sedimentary rocks made mainly of pieces (clasts) of preexisting rocks or minerals. Weathering loosens those fragments; they are transported and deposited, then buried, compacted, and cemented into rock.

USGS describes common clastic sedimentary rocks by grain size: shale (mostly clay), siltstone, sandstone, and conglomerate (pebbles in a finer matrix). Clastic rocks are the group many people first picture when they think of sedimentary rocks, alongside biologic and chemical sedimentary types such as some limestones.

Source: What are sedimentary rocks? — U.S. Geological Survey (USGS)

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