The striations in the photo are on rocks in the Indian Peaks Wilderness, Utah. Although the striations allow you to determine the orientation of flow, you need other clues to determine the actual direction of flow. In mountainous regions, flow will always be from higher to lower elevations. Although the surrounding topography is not visible in the photo, that topography indicates the ice flowed from the bottom right to the upper left of the photo.

Photo: B. Ford. Used with permission.