North Carolina General Contractors Practice Exam

Sedimentary rock is typically formed through a process known as lithification, which involves the compression of sediments under significant pressure from overlying materials. Over time, layers of sediments, which can include minerals, organic materials, and fragments of other rocks, accumulate at the Earth's surface or on the ocean floor. As more layers build up, the weight of the overlying materials exerts pressure on the lower layers, causing them to compress and eventually cement together to form solid rock. This process highlights the importance of sedimentation in the rock cycle, where materials broken down from existing rocks undergo deposition, compaction, and cementation to form new rock types. While sedimentary rocks can also originate from the erosion of other rock types, it is the compression of these sediments that ultimately turns them into sedimentary rock.