Joints: Planar cracks, no movement across the joints. Joints may have various origin. Joints develop during the exhumation of igneous bodies such as granites. During exhumation the drop in temperature causes the body to contract as minerals occupy of smaller volume as they cool down. This volumetric contraction causes the opening of joints. In volcanic rocks (such as that of Devil Tower, Wyoming) joints may develop a pattern called columnar jointing that breaks the rock in regular octaedric rods.
Fractures: Planar cracks with displacement across the fracture plane. In "extensional fracture" (bottom righ), the displacement is perpendicular to the fracture plane, in "shear fracture" (east-west fractures on the bottom left picture) the displacement in parallel to the fracture plane.
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