Vocabulary • SEDIMENTS • Materials that settle out of water or air. • FOSSILS • The remains or trace of an organism from long ago.
Sedimentary rocks… sediment + compaction/ cementation Mineral “cement” = sedimentary rock Conglomerate Limestone Develop when loose material gets pressed/cemented together
What can make up sediment? Loose rock pieces Plant pieces Animal remains Loose mineral pieces How do sedimentary rocks form? From of sediment that build up on OR
Sedimentary rocks from plants?? Coal is made up of plant remains: dead wood, bark, leaves, stems, and roots. As plants die, they form layers. Then layers of other sediment are buried on top of plant layers, compacting and cementing into coal.
Sedimentary rocks from shells?? Limestone is made up of shells and skeletons of ocean organisms. When organisms die, the shells and skeletons settle on the ocean floor and make layers. Over time the layers are buried, pressed, and cemented together, making limestone.
Sedimentary rocks tell us about the past: Crossbeds Fossils Mud Cracks Ripples show that rocks formed where the area was very wet , followed by a dry period. show water and wind direction and movement of water creatures can tell us that the area was covered by a lake or ocean long ago. show us the direction sand dunes and sand bars were moving
Which rocks are sedimentary? Drag the green ovals over the sedimentary rocks. Why? Iron Ore Shale Limestone Chert Breccia Marble Quartzite Sandstone Pegmatite Scoria
More on the Rock Cycle • ROCK CYCLE TEST • http://www.neok12.com/diagram/Types-of-Rocks-01.htm • Rock Cycle • http://www.classzone.com/books/earth_science/terc/content/investigations/es0602/es0602page02.cfm