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Pyroclastic flows at Medicine Lake Volcano

Small local pyroclastic flows could occur on the upper parts of the volcano during emplacement of silicic lava flows similar to Glass Mountain and Little Glass Mountain.

Most silicic eruptions would be located near the center of the volcano and associated pyroclastic flows would likely travel only short distances, probably 1 km (0.62 mi) or less, from the vents or collapsing flow fronts. An eruption generating large pyroclastic flows is extremely unlikely, although not unprecedented at Medicine Lake volcano. One such eruption took place at the center of the volcano about 180,000 years ago, contributing to formation of a summit caldera and feeding highly mobile, hot, volatile-rich pyroclastic flows down the flanks of the volcano. Any such eruption would destroy everything in its path, but the probability of such a high-consequence event is considered negligible.