On their page, Rocks or Idaho; Harvey, Jacqueline, Vita Taube, and Diana Boyackarth state that the earth contains three types of rocks: igneous, metamorphic, and sedimentary rocks. Sedimentary rock makes up the majority of rocks on earth. The earth contains seventy-five percent sedimentary rock. 70% are sedimentary rocks found on the earth's surface, the remaining 5% are found in the earth's crust. Sedimentary rocks form in two main stages. The first ocean waves, rivers, glaciers, wind or landslides carry solid and loose particles from weathering and the erosion of pre-existing rock. The particles are called sediment (Rocks of Idaho). Subsequently the loose sediment is converted into sedimentary rock by compaction, cementation and recrystallization. Compaction occurs when air and water are forced out of the bottom layer of sediment as more layers build up and press on it. Cementation occurs when sediment is cemented together with natural cements such as calcite and silica. This process of converting loose sediment into sedimentary rock is called lithification (Rocks of Idaho). Recrystallization occurs when unstable minerals recrystallize to form more stable minerals (South Carolina Geological Survey). Rocks form in places where there was once water. Dead animals, plants, and pieces or minerals of rock carried by wind, water, ice, and gravity sink to the bottom of bodies or water. When the body of water dries up, the rock becomes a surface layer. There are three basic types of sedimentary rock: classical, chemical and organic. Classical sedimentary rocks are formed from debris resulting from mechanical weathering. Examples are breccia, conglomerate, sandstone and shale. Chemical sedimentary rocks form when dissolved materials precipitate...... center of paper......h rounded edges. Moderately rounded rocks are found between well-rounded rocks and slightly rounded rocks (Sedimentary rocks and rock cycle). Works Cited ● "Sedimentary Rocks." ThinkQuest. Oracle Foundation and Web. 02 December 2013. ● Science. Np, nd Web. December 1, 2013. .→ Harvey, Jacqueline, Vita Taube, and Diana Boyack. “Idaho Rocks.” Np, nd Web. 2 December 2013. .→ Lucas, Chris and Kate Seigfried. “The Rock Cycle Website: Cementing and Compaction.” The rock cycle. Np, 4 December 2000. Web. 02 Dec. 2013. .# "Sedimentary rocks and the rock cycle". South Carolina Geological Survey, nd Web. 2 December. 2013.