00851nam a2200205 a 450000100080000000500110000800800410001910000180006024500380007826000420011652003900015865000100054865000090055865000130056765000140058065000090059465300130060365300110061670000180062716438272017-08-09       1951    bl uuuu      00u1 u    #d1 aTURNER, F. J.  aIgneous and metamorphic Petrology  aMcgraww-hill mbook company,inc.c1951  aDefinition and classification of different kinds of rocks are essential in furnishing a language by which petrological concepts may be conveyed and observational data concerning rocks may be intelligibly recorded.However,there is no general agreement as to the most satisfactory basis of classification or as to the extent to which precision of definition is desirable and practicable.  arocks  aSoil  aGeologia  aPedologia  aSolo  aMinerais  aRochas1 aVERHOOGEN, J.