| | Encyclopedia: Porosity |
 | | Porosity is a fraction between 0 and 1, typically ranging from less than 0.01 for solid granite to more than 0.5 for peat and clay, although it may also be represented in percent terms by multiplying the fraction by 100%. |
| | Porosity in rocks originates as primary porosity during sedimentation or organogenesis and as secondary porosity at later stages of the geological development [ 1 ]. |
| | In sedimentary rocks the porosity is further classified as intergranular porosity between grains, intragranular or intercrystalline porosity within grains, fracture porosity caused by mechanical or chemical processes, and cavernous porosity caused by organisms or chemical processes. |
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