Dott classification

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Dott classification A widely used classification of sandstone types which divides sandstones into arenites (less than 15% of rock is mud matrix) and wackes (more than 15% but less than 75% of the rock is mud matrix). The arenites are subdivided into quartz arenite (more than 95% quartz grains), arkosic arenite (more than 25% feldspar and more feldspar than rock fragments), subarkose arenite (5–25% feldspar grains and more feldspar than rock fragments), lithic arenite (more than 25% rock fragments and more rock fragments than feldspar), and sublitharenite (5–25% rock fragments and more rock fragments than feldspar). The wackes are divided into quartz wacke (more than 95% quartz grains), lithic wacke (more than 5% rock fragments and more rock fragments than feldspar), and feldspathic (arkosic) wackes (more than 5% feldspar and more feldspar than rock fragments).