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
- Rythmical stratification
- Graded stratification
- Cross stratification(oblique stratification)
The classification of common types of sedimentary rocks: