Pahoehoe, Volcano national Park, HawaiiThere are limited types of rock that solidifies on the surface from lava flows. The rope-like appearance is formed as the surface cools and starts to stiffen and slows but the underlying flow is still moving.
This particular image was captured on the walk along the lower slope of Kīlauea. Kīlauea, as with the other present and past Hawaiian volcanoes exist due to a hot spot in the Earth's mantle. A plume of magma extends toward the surface and as the Pacific plate moves, successive volcanoes form islands. Since the lava comes from deep within the Earth, the composition is fairly mafic in character (iron rich) as opposed to the more bubbly and explosive silica-rich lavas of the plate edge volcanoes (think Mt. St. Helens, Chilean volcanoes, or Mt. Vesuvius). |
Why were we there?
|