valley bulging An upward arching of the bedrock along the axis of a valley. It may not be visible at the ground surface due to subsequent erosion, but it is revealed by the distortion of the geologic structure. It may be due to frost heave, or to the compressive forces set up when two opposing valley sides approach each other.

valley bulging An upward arching of the bedrock along the axis of a valley. It may not be visible at the ground surface, owing to subsequent erosion, but it is revealed by the distortion of the geologic structure. It may be the result of frost heave or the compressive forces set up when two opposing valley sides approach each other.