Non-detrital rock

Non-detritus rocks are sedimentary rocks whose formation involves chemical processes. The simplest of these is precipitation; ie the formation of a solid compound from the solute of a saturated solution (for example, limestone is formed). In other cases complex processes occur in which the decomposition and transformation of remains of living beings occurs, as in the case of coal.

The three most important groups of non-detritus sedimentary rocks are carbonates, evaporites and organogens.

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