SUMMARY:Type: composite cone |
GEOLOGIC HISTORYMt. Melbourne, one of two known active volcanoes in the Ross Sea embayment, is a 2733-m-high composite volcano compsed predominantly of lavas ranging from trachyandesite to trachyte. The glacier-clad stratovolcano lies at the center of a volcanic field containing both subglacial and subaerial vents that are situated along a dominantly N-S trend. A large number of scoria cones, lava domes, viscous lava flows, and lava fields are exposed at the summit and upper flanks. A number of very young-looking cones are located at the summit and on the flanks. Tephra layers are found within and on top of ice layers, and the most recent eruption may have been only a few hundred years ago. The volcano displays fumarolic activity that is concentrated along a NNE-SSW line cutting through the summit area and along a line of phreatomagmatic craters on the southern rim of the summit crater. Prominent ice towers and pinnacles were formed from steam condensation around fumarolic vents. Historic Activity: No historic activity. Recent Activity: The volcano displays fumarolic activity that is concentrated along a NNE-SSW line cutting through the summit area and along a line of phreatomagmatic craters on the southern rim of the summit crater. Prominent ice towers and pinnacles were formed from steam condensation around fumarolic vents. Data Sources
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ADDITIONAL INFORMATION
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Last Update: 2/13/00 |