Sedimentary Rocks Where sedimentary rocks come from? Sediments Can you think of an example of sedimentary rock? Sandstone, shale, limestone, conglomerate… What processes are involved in the formation of sedimentary rocks? Compaction and Cementation What is a sedimentary rock? • Sedimentary rocks are formed by the accumulation of inorganic and organic sediments which undergo compaction and cementation to form rock Coal is a sedimentary rock Compaction Cementation Heat and Pressure Sedimentary Rocks are classified based on their components Clastic Organic Chemical 1.) Conglomerate 1.) Coal 1.) Limestone 2.) Sandstone 3.) Shale 2.) Fossiliferous Limestone 2.) Salt Environments affect the type of sediment Environments change throughout geologic time Where you think these rocks are from? GRAND CANYON!!! Superposition • The law of Superposition tells us that the older rocks are at the bottom of the rock section and the youngest rocks are at the top of the rock section Rock Section activity • Create your own sedimentary rock section by filling in a plastic container with at least sediments from the different environments • Make sure not to overfill the plastic containers Wrap up questions write on the back of your handout • • • • • • Describe the layers in your cross section How many layers are there? What were the environments of deposition? Which order the layers go in? Which layer is the oldest? Which layer is the youngest? Different environments produce different sedimentary rocks Different environments produce different sedimentary rocks Different environments produce different sedimentary rocks Different environments produce different sedimentary rocks Climates have been changing for billions of years • http://www.ucmp.berkeley.edu/geology/anim1.html Climate change occurs naturally, but we aren’t sure why Wisconsin Stage (26,000 to 13,300 years ago) Recently, scientists have seen a global warming trend coinciding with Industrialization Climates have changed dramatically in Pennsylvania [...]... different sedimentary rocks Different environments produce different sedimentary rocks Different environments produce different sedimentary rocks Different environments produce different sedimentary rocks Climates have been changing for billions of years • http://www.ucmp.berkeley.edu/geology/anim1.html Climate change occurs naturally, but we aren’t sure why Wisconsin Stage (26,000 to 13 ,300 years