The sapping may have left a cavity and the crater was formed when the surface collapsed to fill the void. There are many flaws to this theory. First off, why don't we see these craters elsewhere on Io like near Tvashtar Catena or Telegonus Mensa. Secondly, no one knows if the cliff has undergone sapping. It couldn't be a caldera because it is unlike any caldera found on Io.
Most active ones are dark, and none occurs on top of mountains.
This is a bowl shapped crater with a flat bottom, which is consistent with other craters its size. The color on the inside of the caldera is the same as the outside, no caldera shows this relationship. It appears to be 4-6 km across, but since I have nothing to compare it too in that mosaic, it could be as large as 14 km wide. A few weeks ago when I announced my discovery of the crater, I also mentioned another possible cause of the crater. I said since the crater was near a cliff, and other cliffs on the same mountain have features that indicate sapping has occured, I said it was possible that the crater was caused by sapping at the cliff.