Chapter 6 - Sedimentary Rocks Flashcards
What are the three main types of sedimentary rocks?
Detrital, chemical, and organic.
What is lithification?
The process of turning sediment into rock through compaction and cementation.
What is the difference between conglomerate and breccia?
Conglomerate has rounded particles, while breccia has angular particles.
What is the main mineral in limestone?
Calcite.
What are evaporites?
Sedimentary rocks formed by the evaporation of water, leaving behind minerals like halite and gypsum.
How do sedimentary structures like cross-bedding, graded bedding, and ripple marks provide clues about past environments?
By indicating water or wind movement, helping geologists infer the energy, direction, and environment of deposition
How does the process of diagenesis alter sediments after deposition?
Diagenesis involves physical, chemical, and biological changes, such as compaction and cementation, that transform loose sediments into solid sedimentary rock.
What are sedimentary rocks?
Rocks formed from mechanical and chemical weathering. They often contain fossils and provide clues about past environments and sediment transport.
Why are sedimentary rocks economically important?
They contain valuable resources such as coal, petroleum, natural gas, and materials like iron, aluminum, and construction raw materials.
Name the types of sedimentary environments.
Continental – dominated by streams, glaciers, and wind.
Transitional – shorelines with deltas, lagoons, and beaches.
Marine – shallow and deep ocean environments.
What are detrital sedimentary rocks made of?
Primarily composed of clay minerals, quartz, feldspars, and micas. These particles are transported and deposited by water, wind, or ice.
What is shale?
A detrital sedimentary rock with clay- to silt-sized particles. It often forms in quiet water environments and has thin layers called laminae.
What is sandstone?
A sedimentary rock made of sand-sized particles, commonly quartz. It forms in various environments like rivers and deserts and shows sorting and roundness.
