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A beautifully preserved interior ledge inside a pillow crust recovered in Dredge #41 today. These ledges form when some lava inside the chilled outer crust of a newly formed pillow drains out quickly from the center. The lava remaining inside continues to cool and forms horizontal layers of crust inside the outer crust. Then, if the pillow cracks and the rest of the lava spills out, what remains is a lava pillow with the original outer crust and one or more inner shelves of lava. Tim Haskell’s fingers are shown for scale.

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