Little Juniata River

The elevation of the cave in relation to local base-level may also serve to constrain the age of the cave. The morphology of the cave makes it reasonable to believe that it formed at or above local base-level. The lowest portions of the cave are presently at about 53 ft. (16 m) above the Little Juniata River. As an end-member calculation, let us assume that the cave formed at base-level and had a negligible gradient toward the surface stream. Furthermore, let us assume an incision rate of 0.05 m/ka (Sasowsky et al., 1995). Under such conditions the river could have cut this distance below the cave in 320 ka, yielding a similar age for the cave. Because we do not know the actual gradient that was present when the cave formed, this number should be considered a maximum possible value. 

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