Okay the next thing I wanted to share with this group is what looks like steps, or stepped blocks (not necessarily for walking on). I first noticed this feature in the sonar images and figured it might be steps since in the scene where it shows them the sonar expert is saying that "it's an opening", meaning that its a square tunnel exiting the chamber. The things that look like they might be steps lead up to that opening. Then a few days ago I found an identical looking block with a stripe down the middle of it, also arrayed in very step like fashion. Here we have an image from Dan Blankenship's film from 1971 on the left, and an image from the sonar from the season finale on the right. I have an arrow pointed to the step in each image that is the most clear.
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