In one embodiment, a method includes obtaining a borehole image deriving from a downhole tool in a wellbore of a geological formation, identifying one or more patches that correspond to sediment particles on the fullbore image, computing one or more characteristics for each of the one or more patches. The one or more characteristics may include long/short axis length, size, roundness, sphericity, orientation, or some combination thereof. The method may also include displaying a visual representation for each of the one or more characteristics.