1. AIM: How are sedimentary rocks formed, classified and used? OBJ: Given notes and activity sheet SWBAT explain how sedimentary rocks are formed, classified and used with 70% accuracy. DN: HW Check- Igneous Rock Activity Sheet Watch video https://www.youtube.com/watch?v=wxX8KPzV6xU ACT: Introduction to Sedimentary Rocks (Notes) Text, Read p.152-156 HW: Complete Sedimentary Rocks Activity Sheet; Work on MR Review Sheets; Mineral & Rocks Exam, March 20 https://www.youtube.com/watch?v=wxX8KPzV6xU

2. Sedimentary Rock Notes Sedimentary Rock: forms when sediment undergoes erosion, deposition, accumulation, compaction and/or cementation. Sediment: small, solid pieces of rock or living things (seashells, bones, leaves, stems). Weathering: breakdown rock (mountains) into sediment by: Physical weathering: ice wedging, collision of particles by abrasion in running water or wind action Chemical weathering: dissolution by organic acids, acid rain. Erosion: transport/movement of sediment by running water, ice or wind.

3. Acid Rain Frost Action Ice Wedging Cave Formation Exfoliation / Unloading Root Wedging

5. Sedimentary Rock Notes

6. Deposition: the process by which sediments settle out (to the bottom) from a column of water or wind carrying it. Accumulation/Burial: the build up of sediments from bottom to top froming thick layers gradually over long periods of time. Compaction: accumulated sediments squeeze together under great pressure Cementation: sediments glued together as natural mineral cements harden from solutions.

7. Deposition of Sediments decreasing siltstone shale chemical limestone conglomerate sandstone

8. Types of Sedimentary Rock Sedimentary Rocks are classified into 3 major groups based on the type of sediments: Clastic/Fragmental Rocks: Most sedimentary rocks are made up of broken pieces of other rocks (rock fragments) which underwent compaction and possibly cementation. Clastic rocks are classified based on the size & shape of the rock fragments. Example: Shale - clay particles Siltstone – silt Sandstone – sand Conglomerate – rounded pebbles/gravel Breccia – angular pebbles/gravel

9. Sedimentary Rock Notes Organic/Bioclastic Rocks: form from the accumulated remains of plants & animals into thick layers under compaction and/or cementation. Example: Coal – remains of plants Coquina – remains of seashells loosely cemented together Fossiliferous limestone – remains of seashells, dense, well cemented together.

10. Sedimentary Rock Notes Crystalline/Chemical Rocks: the process by which minerals that are dissolved in a solution, crystallize out by evaporation and precipitation. Example: Chemical limestone – dissolved calcite in ocean water precipitates out; homogeneous, microcrystalline, no fossils Rock salt – evaporation of inland seas, lakes

11. Sedimentary Rock Notes Uses of Sedimentary Rocks Tools – flint arrowheads for hunting Building – limestone & sandstone (White House, Washington, DC) Cement & Steel – limestone used.