Lithological factor sediments

The presence of particles in the fluid medium complicates diffusion in a sediment due to the effects of porosity, represented by n, and tortuosity. Since tortuosity of natural sediments is seldom known it is more convenient to use the term "formation factor" or "lithological factor," denoted L, which takes into account everything but porosity. Tick s diffusion constant D is replaced by the whole sediment diffusion constant Ds, where < D. 

The most important factor controlling sediment compaction is the sediment composition since both the mechanical and the chemical processes are so dependant on the lithology. 

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