Which metric is used to quantify vertical displacement in offset beds?

• A. Dip
• B. Throw
• C. Dip-slip
• D. Heave

Answer: (B)

Throw is the vertical movement that occurs when a fault displaces beds. It represents how far a marker bed on one side of the fault sits above or below the corresponding bed on the other side. This vertical separation is what we refer to as the throw. It’s different from heave, which is horizontal displacement along the strike, and from dip, which is the angle of the fault plane. Dip-slip describes motion along the fault plane but does not itself quantify vertical offset. So when you see offset beds and you’re asked to quantify the vertical displacement, you’re looking at the throw.