In an unconformity, the rocks on opposite sides are not parallel, then its is 

Joints perpendicular to the axes of folds are common in orogenic belts, such joints are called

Oscillation ripple marks can readily be used to identify whether a bed is right-side-up or 

In a fold, the downward-facing beds are 

The strike direction is commonly recorded like -------- using quadrant bearing from the north point.

The tangent of the angle between horizontal and the inclined surface is called