Sedimentary rocks are important for economic considerations because
they may contain Coal Petroleum and natural gas Sources of Fe, Al, and Mn
Detrital sedimentary rocks
transported sediment as solid particles
Chemical sedimentary rocks
sediment that was once in solution
Organic sedimentary rocks
detrital rocks include
Clay minerals Quartz Feldspars Micas
Mud-sized particles in thin layers that are called laminae Parallel alignment of grains Barrier to flow of water Low energy environments of deposition Most common sedimentary rock--can be shales, mudstones, siltstones
Rock composed mainly of sand-sized particles Forms in a variety of environments Described by Sorting Particle shape Composition Predominant mineral = quartz
Conglomerate consists largely of
Breccia is composed mainly of large
evaporation, chemical activity
-life processes of water-dwelling organisms
Most abundant chemical rock Composed chiefly of the mineral calcite Marine biochemical limestones form as coral reefs, coquina (broken shells), and chalk (microscopic organisms) Inorganic limestones include travertine and oolitic limestone
Typically formed secondarily from limestone
Microcrystalline quartz Varieties include flint, agate, and jasper
Evaporation triggers deposition of chemical precipitates
Different from other rocks because it is composed of organic material 1. Plant material 2. Peat 3. Lignite 4. Bituminous coal
Chemical, physical, and biological changes that take place after sediments are deposited and lithified. Occurs within the upper few kilometers of Earth's crust
Two major textures are used in the classification of sedimentary rocks
Discrete fragments and particles All detrital rocks have a clastic texture
Pattern of interlocking crystals May resemble an igneous rock
Types of Sedimentary Environments
Continental Marine Transitional
Marine Sedimentary Environments
Types of sedimentary structures
Graded beds Ripple marks Mud cracks Fossils
A sedimentary facies is the sedimentary rock's ________.
environment of deposition
Which of the following sedimentary rocks would you expect to have originally been deposited by fast-moving streams?
Oolitic limestone is most likely to form in what type of depositional environment?
shallow, clear marine waters with vigorous current activity
If shale is such a common rock in the sedimentary rock world, why isn't it as prominently exposed at the surface as sandstone?
Which of the following is a feasible explanation as to why quartz sandstone is an excellent use of "uniformitarianism"
Layers of sand-size quartz-rich sediment found today at the beach are virtually identical to layers in a 10-million-year-old sandstone, thus suggesting the location of the sandstone was the location of a beach 10 million years ago.