Do sedimentary rocks contain shells and skeletons of marine animals?

Yes, sedimentary rocks often contain shells and skeletons of marine animals. These fossils form when sediments accumulate and lithify, preserving the remains of organisms that lived in aquatic environments. Common examples include limestone, which can contain fossilized coral and shell fragments, and shale, which may include tiny shells or remnants of marine life. The presence of these fossils provides valuable insights into the Earth's history and past ecosystems.