Sedimentary rocks

Rubbled sedimentary rocks:

• Formed through the distraction and crumbling of surface rocks.

• Consist of grains
• The base of classification is the size of grains
  • Psephital sediment: gravel stone, gravel
  • Psammital sediment: sand
  • Pelital sediment: aleurite, clay
• Psephital and psammital sediments consist of mainly quartz, pelital consist of mainly clay minerals.

Characteristics of rubbled sediments:

• Classification: marks the dimension range
• Thinning, sphericity
• Stratification
  • Rythmical stratification
  • Graded stratification
  • Cross stratification(oblique stratification)

The classification of common types of sedimentary rocks: