This equation can be rearranged to find diameter using φ : In some schemes , gravel is anything larger than sand ( comprising granule , pebble , cobble , and boulder in the table above ) .
In some schemes `` gravel '' is anything larger than sand ( ) 2.0 mm ) , and includes `` granule '' , `` pebble '' , `` cobble '' , and `` boulder '' in the above table .