Classification of sedimentary rocks      After transportation and deposition loose sediments are consolidated into sedimentary rocks by a process called diagenesis. The sedimentary rocks thus formed may be broadly divided into two groups: Exogenetic and Endogenetic      Exogenetic  rocks are the products of fragmentation of the source rock outside the basin of sedimentation.  Endogenetic  rocks are produced out of precipitation from solution within the basin. The exogenetic and endogenetic rocks can be distinguished by their textures. While the endogenetic rocks show an interlocking or crystalline fabric (‘non-clastic’ texture), the exogenetic rocks show discrete framework grains separated by voids. The latter texture is called ‘clastic’ from the Greek clastos, meaning broken      Classification of sedimentary rocks into  clastic  and  non-clastic , though popular among sedimentologists, may at times lead ...