Height:
11,249′ (3,426 m) 28th most prominent peak in the US
Diameter:
~12 miles (2o km)
Type of Mountain
Stratovolcano (composite volcano), dominated by andesite magmas.
Location:
50 miles, 70 km east of Portalnd, Oregon, USA, 45° 22’25” West, 121°41’45 North
1859, 1865 – Settler reports of glowing sky and steam explosions, no known rock deposits of this age
1782 CE – Old Maid eruptive phase. Lava dome, pyroclastic flows and lahars
~1500 years ago – Timberline eruptive phase. Lava dome, pyroclastic flows, sector collapse and landslide, lahars
~7,700 years ago – flank lava flow near Parkdale, OR
12,000 to 30,000 Polallie eruptive phase. Multiple lava domes, lava flows, pyroclastic flows and lahars
Mount Hood Research 