SANDSTONE CLASSIFACATION BY FOLK





QFR diagram for Folk's sandstone classification

  

Folk proposed a classification for sandstones based on the relative abundances of quartz (Q), feldspars (F), and rock fragments (R). These are the main poles of the classification diagram.

Volcanic rock fragments (VRFs), metamorphic rock fragments (MRFs) and sedimentary rock fragments (SRFs).

The petroleum geologist, for example, is interested in identifying rock types in outcrops, drilling cuttings, and core samples. Standardization and a classification scheme can make his work easier.

Sent in by Ekwe Umahi Makolia, TalkOil9ja.