This is a difficult question to answer because the initial eruptive temperatures — along with many different factors — can influence the rate of cooling.
Eruptive lava temperatures of the LERZ eruption reached a maximum of approximately 1, degrees Celsius 2, degrees Fahrenheit.
When the entire flow cools to below about 1, degrees Celsius 1, degrees Fahrenheit , it has solidified, but the interior is still very hot.
Arguably the most influential factor determining how fast lava cools is the thickness of the flow. Other factors include heat loss from the top to the atmosphere and bottom of a flow into the ground. The initial contact between a lava flow, the air above it and ground surface below it quickly hardens its outer crust top and bottom.
This is because the crust is a good insulator, meaning it poorly conducts heat — similar to how an insulated thermos keeps liquid inside hot. After the initial formation of crust, the flow continues to lose heat through radiation and conduction, facilitated by wind and rain.
This steaming can persist for decades, long after the lava solidifies, depending on the thickness of the flow and the temperature of its interior. Based on a study of crustal cooling of pahoehoe lava flows in Kalapana erupted from the East Rift Zone Kupaianaha vent in , we can estimate the solidification time for the LERZ flows.
But because the core of each flow type should cool at similar rates, we are basing cooling rates on the study. Also of note, the flows studied in were much thinner with shorter cooling rates and might not account for long-term changes in wind and rain patterns.
Preliminary analyses of the LERZ eruption flow thicknesses suggest the average flow thickness is about m ft. The thickest LERZ flows on land, which are about 55 m ft thick, might take roughly 20 years to reach a completely solid state. They are very common on fast-spreading mid-ocean ridges such as the East PacificRise.
Sheet flows form at much higher eruption rates than pillow flows. The high eruptionrates allow rivers of lavas to form that can flow across the seafloor.
Theserivers can fill low areas in the seafloor and form lava ponds with very flatsurfaces. Lava in the ponds can also spread like thick pancake batter on a tiltedgrill, forming a long tongue-like flow.
Sheet flows can have flat surfaces aswell as twisted, ropy ridges all aligned in the direction that the flow movedacross the seafloor. Lava tubes are tunnels that form within a lava flow during an eruption. As lavaflows away from a volcano, the surface chills quickly and insulates the stillmolten lava beneath.
Rivers of lava can continue to flow for great distancesin the tunnel beneath the chilled and solidified surface before it cools andbecomes hard rock. As the eruption slows down and lava stops flowing, the molten lava drains fromthe tube leaving a long hollow cave. These tubes can be several kilometers longand many tens of meters in diameter.
The Thurston lava tube, near the calderaof Kilauea volcano on Hawaii, is a famous large lava tube that has been a touristattraction since the late s when Mark Twain visited the islands. On land, lava tubes are currently forming in eruptions at Kilauea volcano inHawaii and at Etna volcano on the island of Sicily in Italy.
Old lava tubes arecommon on many volcanoes. There are lava tubes near the summit of the volcanoon Santa Cruz Island. More: Hawaii volcano's massive ash eruption is biggest in 12 days — but not as serious as some have feared.
More: Before and after: Satellite images show devastation of the Leilani Estates neighborhood from Hawaii volcano. Like many evacuees who had time, Donovan emptied her home of valuables, including her solar system and backup batteries.
April Buxton has also removed most of her valuables, although she refuses to empty her house entirely. That, she said, would be inviting trouble from goddess Pele. Buxton, who is semi-retired, said most of her money is sunk into the house.
She's used much of her savings to buy supplies to make the Pahoa tent city more comfortable for her and her neighbors, from the pop-up shelters to the food they prefer to what the Red Cross offers.
In my mind, if I empty it, she'll take it," Buxton said. Facebook Twitter Email. It will be months before lava from Hawaii volcano can be removed from neighborhoods. Show Caption. Hide Caption. Hawaii residents coping with volcano danger. Emissions from Hawaii's Kilauea volcano diminished Wednesday, a day after a plume of ash spewed from the crater in a massive cloud that rose some 12, feet.
Residents and scientists are keeping a close watch for more violent activity. May Share your feedback to help improve our site!
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