I don’t believe there is any interpolation between frames. The entire sequence consists of 22 images acquired over a roughly 20 minute period. I believe the melting effect you’re referring to could the loose regolith dropping into the fractures between the plates. In addition the original was an MP4 file (see link in the post). This Lemmy instance does not support MP4 uploads so I had to convert it to a GIF, there could be some image artifacts from that conversion process, so try watching the original MP4 animation in the link :) Or check the original HazCam images on the mission image server.