Bootsmansrots ('Bosun's Rock' in Dutch) is a small (about 10 m squared) platform of rock composed of parallel slabs of hypersthene andesite tilted at about a 45-degree angle to the sea surface. It probably was an extrusion dike in the flank of Danan and was stable enough to keep Danan from being destroyed in the major explosion at 10:02 am which destroyed the area to the south and the northern half of Rakata. The steep angle to the west indicates that it has moved from its original location, probably by the bulk of Danan collapsing in that direction.
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