Question

How do detrital sedimentary rocks differ from chemical sedimentary rocks? Explain how the soil pedon contains all aspects of mechanical and chemical weathering leading to sedimentary rock formation (include all of the different layers and the different types of rocks they would represent if exposed to the surface).

Answer 1

Detrital sedimentary rocks are called as clastic rocks whereas chemical precipitate sedimentary rocks are called as non-clastic rocks. They differ from each other in different aspects like texture, mode of occurrence etc.

The texture of the clastic sedimentary roca mainly decided by its shape, size, and to some extent mineralogical composition. Size and shape matters a lot. The more the transportation the more rounded the shape will be and the more the maturity. Clay percentage decides about the mineralogical maturity. These rocks are harder in comparison to the non-clastic rocks.

Whereas non-clastic rocks shows interlocking type precipitation texture. Here shape, size classification is not valid. These are smoother rocks.

Examples of clastic or detrital sedimentary rocks include sandstone, shale, breccia, conglomerate etc. Whereas non-clastic sedimentary rocks include limestone, chert, halite, evaporites etc.