Kilauea strikes awe and fear

WHAT GASES ARE EMITTED DURING AN ERUPTION? US Army National Guard First Lieutenant Aaron Hew Len takes measurements for sulphur dioxide gas at volcanic fissures in Pahoa on May 8. Many different gases are emitted into the air during a volcanic erupti — HOW DO VOLCANOES FORM? A view of the entire north portion of the Overlook crater as the eruption continued at Hawaii's Kilauea volcano on May 6. The Earth's outer crust is made up of tectonic plates that fit together like a jigsaw. Volcanoes can form where two plates meet, but they can also develop in the middle of a plate or a "hot spot", where magma beneath the Earth's crust erupts on the sea floor. Scientists say the Hawaiian islands were formed by such a hot spot in the middle of the Pacific Plate. However, while the hot spot is fixed, the plate is moving due to convection currents in the Earth's mantle. So, as the plate moved over the hot spot, the string of islands that make up Hawaii was formed. The Big Island, where Kilauea is located, is one of eight main islands that make up the state of Hawaii. PHOTO: UNITED STATES GEOLOGICAL SURVEY

WHAT GASES ARE EMITTED DURING AN ERUPTION? US Army National Guard First Lieutenant Aaron Hew Len takes measurements for sulphur dioxide gas at volcanic fissures in Pahoa on May 8. Many different gases are emitted into the air during a volcanic erupti — HOW HOT IS LAVA? Lava erupts from Kilauea on May 23. The temperature of lava varies, but scientists can estimate its temperature by its colour. Geophysicist Mika McKinnon said yellow lava is the hottest, at somewhere between 1,000 and 1,200 deg C, while orange lava can be between 800 and 1,000 deg C. Red lava is the coolest, at 600 to 800 deg C. PHOTO: AGENCE FRANCE-PRESSE

WHAT GASES ARE EMITTED DURING AN ERUPTION? US Army National Guard First Lieutenant Aaron Hew Len takes measurements for sulphur dioxide gas at volcanic fissures in Pahoa on May 8. Many different gases are emitted into the air during a volcanic erupti — Officials from the United States Geological Survey observe lava erupting at Hawaii's Leilani Estates on May 24. Fissure eruptions, characterised by a curtain of lava spewing out to a small height, occur when magma flows up through cracks in the ground and leaks out onto the surface. These eruptions can produce very heavy but slow-moving lava flows. PHOTO: REUTERS

WHAT GASES ARE EMITTED DURING AN ERUPTION? US Army National Guard First Lieutenant Aaron Hew Len takes measurements for sulphur dioxide gas at volcanic fissures in Pahoa on May 8. Many different gases are emitted into the air during a volcanic erupti — Lava from a reactivated fissure vent in Pahoa, Hawaii, consumes two storage warehouses of the Puna Geothermal Venture facility on May 22. Earlier this month, officials removed a flammable gas called pentane from the plant to reduce the chance of explosions. They also shut down the geothermal plant shortly after the eruption began. PHOTO: EPA-EFE

HOW DO VOLCANOES FORM?A view of the entire north portion of the Overlook crater as the eruption continued at Hawaii's Kilauea volcano on May 6. The Earth's outer crust is made up of tectonic plates that fit together like a jigsaw. Volcanoes can form — WHAT GASES ARE EMITTED DURING AN ERUPTION? US Army National Guard First Lieutenant Aaron Hew Len takes measurements for sulphur dioxide gas at volcanic fissures in Pahoa on May 8. Many different gases are emitted into the air during a volcanic eruption, including some that are toxic. The US Geological Survey says the most abundant gas is water vapour, which is harmless. However, other gases emitted during an eruption, such as hydrogen sulphide and hydrogen halides, can be toxic. High concentrations of hydrogen sulphide can render a person unconscious in less than five minutes, while hydrogen halides can cause acid rain. The Hawaiian eruption has spewed lava and high levels of sulphur dioxide gas into nearby communities, leading officials to order 1,700 people to evacuate. PHOTO: AGENCE FRANCE-PRESSE

WHAT GASES ARE EMITTED DURING AN ERUPTION? US Army National Guard First Lieutenant Aaron Hew Len takes measurements for sulphur dioxide gas at volcanic fissures in Pahoa on May 8. Many different gases are emitted into the air during a volcanic erupti — An ash plume rises from Kilauea's Halemaumau crater on May 9. Ash and toxic gases from the volcano can cause lung damage and other health problems, especially for infants and the elderly. PHOTO: AGENCE FRANCE-PRESSE

HOW HOT IS LAVA?Lava erupts from Kilauea on May 23. The temperature of lava varies, but scientists can estimate its temperature by its colour. Geophysicist Mika McKinnon said yellow lava is the hottest, at somewhere between 1,000 and 1,200 deg C, whi — WHAT CAUSED THE BLUE FLAMES? The eruption has produced many natural spectacles, including flames of blue, photographs of which have made their rounds on social media. The blue flames, said National Geographic, come from methane gas. Under normal conditions, vegetation breaks down to gradually release methane into the air. However, volcanologist Janine Krippner told National Geographic that the roads act as a cap, containing the methane underground and causing high concentrations of the gas to build up. When it eventually seeps out of cracks in the road, the exposure to oxygen in the air and heat from the lava causes it to ignite, producing a blue flame that is visible only at night. Scientists say that if the gas remains trapped underground and is ignited, it could explode. PHOTO: AGENCE FRANCE-PRESSE

Luke Anthony Tan

Updated

Published

May 31, 2018, 05:00 AM

Hawaii's Kilauea volcano started erupting on May 3, spitting lava more than 60m into the air. The next day, a 6.9-magnitude earthquake left already rattled locals shell-shocked. The ongoing eruption of Kilauea is the largest in decades, destroying more than 40 homes and displacing thousands. Luke Anthony Tan compiles scientific facts to answer the common burning questions about the eruption.

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