Photomicrograph of a foliated cataclasite from the Pasagshak fault on Kodiak Island, Alaska. The protolith is a melange of turbidite deposits and volcanic rocks from the Ghost Rocks Formation (or oceanic igneous and sedimentary rocks from the Kodiak accretionary complex?). The approximately 1 mm long clasts are made of sandstone. The clasts are asymmetric boudins, and the asymmetry can be used to determine the direction of shear, as shown by the red arrows. The dark pressure solution seams also approximate the orientation of shear (Menegheni et al., 2010).

Meneghini, F., Di Toro, G., Rowe, C.D., Moore, J.C., Tsutsumi, A.,  Yamaguchi, A., 2010. Record of mega-earthquakes in subduction thrusts: The black fault rocks of Pasagshak Point (Kodiak Island, Alaska). Geological Society of America Bulletin 122, 1280-1297.