Letting of some Steam
Image taken near the crater of Kilauea Volcano, Hawaii. Ground water seeps down to the hot volcanic rocks in this area and returns to the surface as steam. While standing at the Steam Vents, take a good look around. The area between the caldera’s edge and outer cliffs of Kilauea Caldera is a treeless plain. The ground just a few feet down is so hot that tree roots can not survive. But shallow-rooted grasses and plants grow here.
You may enjoy the short walk on a trail leading from the Steam Vents parking area to Steaming Bluff, on the caldera’s edge. The area is a grassy meadow with ground cracks and steaming concentrated in fractures along the caldera’s edge.
Across from the Steaming Bluff and the Steam Vent parking area is the trailhead to the Sulphur Banks. At Sulphur Banks (Ha`akulamanu), volcanic gases seep out of the ground along with groundwater steam. These gases are rich in carbon dioxide, sulfur dioxide and hydrogen sulfide — the gas that smells like rotten eggs. Some sulfur gases deposit pure crystals at Sulphur Bank. Other sulfur gases form sulfuric acid which breaks down the lava to clay. This clay is stained red and brown with iron oxide.