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Global Volcanism Program | Image GVP-07945

The spectacular giant pumice beds of Primavera volcano represent an unusual sedimentation event following formation of La Primavera caldera.  Individual blocks of inflated pumice from 0.3 to >6 m across are enclosed within fine-grained lake sediments.  The giant pumice blocks originated by eruption of rhyolitic lava into a caldera lake.  The pumice fractured into large blocks that floated to the surface, rafted across the lake, and gently settled to the bottom.  Subsequent deposition of fine-grained lake sediments buried the pumice blocks. Photo by Jim Luhr, 1979 (Smithsonian Institution).

The spectacular giant pumice beds of Primavera volcano represent an unusual sedimentation event following formation of La Primavera caldera. Individual blocks of inflated pumice from 0.3 to >6 m across are enclosed within fine-grained lake sediments. The giant pumice blocks originated by eruption of rhyolitic lava into a caldera lake. The pumice fractured into large blocks that floated to the surface, rafted across the lake, and gently settled to the bottom. Subsequent deposition of fine-grained lake sediments buried the pumice blocks.

Photo by Jim Luhr, 1979 (Smithsonian Institution).


Sierra la Primavera