Where in the World Does Obsidian Hydration Dating Work?

Results of a field study at Pot Creek Pueblo indicate that when effective hydration temperature varies significantly with depth, errors in obsidian hydration age estimates can occur if hydration rate constants are extrapolated to depth-specific effective hydration temperatures. This problem will be particularly severe in continental climates, but will have some effect anywhere the amplitude of the annual surface temperature wave exceeds 2-3°C.