Sedimentary Rocks




This week we learned that most sedimentary rocks are composed primarily of the weathered remains of other rocks. Sedimentary rocks usually form by the compaction and cementing of sediment particles. We also learned that there are three types of sedimentary rocks:
  1. clastic (fragmental rocks), made up of different sized inorganic earth-derived particles;


  2. bioclastic (organic-derived), formed by the accumulation of plant and animal remains;


  3. crystalline (chemical) are deposited by chemical precipitation (settling) of materials from solution in seawater. This occurs during the evaporation of seawater and when compounds are no longer soluble.
  • Fossils, the remains of prehistoric life, are almost always found in sedimentary rocks.

Homework:

In Reviewing Earth Science (Review Book), by Thomas McQuire, do questions 32-44, on pages 41-42. Due Wednesday, February 6, 2008

Also, read pages 43-44 on metamorphic rocks. Do questions 45-52. Due Friday, February 8, 2008.

There will be a test on sedimentary and metamorphic rocks on Friday, February 8, 2008.



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