Spouting Horn of Depoe Bay - Oregon
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Volcanoguy
N 44° 48.757 W 124° 03.764
10T E 415967 N 4962684
Spouting Horn in basalt at Depoe Bay, Oregon.
Waymark Code: WMCYM6
Location: Oregon, United States
Date Posted: 10/26/2011
Views: 15
From American Geosciences Institute’s Glossary of Geology, 5th Ed. the definition of a spouting horn is: “A sea cave with a rearward or upward opening through which water spurts or sprays after waves enter the cave.” Other terms for a spouting horn include blowhole, puffing hole, blow, boiler, buller, spouter, chimney, and oven.
A more detailed definition is: “A nearly vertical hole, fissure, or natural chimney in coastal rocks, leading from the inner end of the roof of a sea cave to the ground surface above, through which incoming waves and the rising tide forcibly compress the air to rush upward or spray water to spout intermittently, often with a noise resembling a geyser outburst. It is usually formed by wave erosion concentrated along planes of weakness, as in a well-jointed rock.”
Here at Depoe Bay the coast line consists of pillow basalts which form when fluid basalt flows enter water. In water during formation the surface of a flow lobe chills instantaneously but fresh lava continues to be injected into the lobe causing it to swell and thus cracking the surface, allowing a new lobe to start and the process begins again.
Along the coast here there are fracture zones which are weaker and the ocean has eroded out sea caves along theses zones. At this location a small hole has developed at the back of the cave to form a blowhole.
More on pillow basalts: (
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