Volcano Watch: Pele’s hair – a beautiful hazard on Hawaiʻi Island : Maui Now
by HVO affiliate Jo Schmith of the Centre for the Study of Energetic Volcanoes / US Geological Survey Hawaiian Volcano Observatory experts and affiliates
Shiny and elusive, featherlight and golden-brown. If poets have been to create about rocks, I’m sure they would sing their praises of Pele’s hair. Really don’t be fooled, however, because Pele’s hairs are strands of volcanic glass, and they can pose a serious hazard.
The fragile hairs conveniently split into very small parts, and no a person desires glass splinters in their eyes or skin that just hold breaking when you try to pull them out. So, go away the hairs be if you locate them.
Pele’s hairs can be a lot more than 1 meter (3 ft) extended and are frequently less than 1 millimeter (.04 inches) thick. For the duration of the recent Mauna Loa eruption in November–December 2022, Hawaiian Volcano Observatory scientists went to discover the Daniel K. Inouye Freeway (Saddle Highway) for erupted materials. Together the sides of the street, they saw strands up to 50 centimeters (20 inches) prolonged, as nicely as clumps of entangled hairs. Observant inhabitants and visitors observed them on the floor at the Mauna Kea customer middle and all the way to Honokaʻa, reporting their findings to HVO.
Pele’s hairs type when molten lava is torn aside. Like the thinning strings that sort when you pull your fingers absent from sticky dough, the hair strands form when blobs of lava are torn apart and the fluid lava still connecting them is stretched slim. The outer skin of the lava is cooled promptly by the air and kinds volcanic glass that freezes this fragile moment in time. Nevertheless, if the pores and skin is cooled far too promptly just before it is stretched slim, it will split into glass parts as a substitute. If the lava is much too sticky, it cannot be stretched enough to type hairs.
That is why Pele’s hairs only type on basaltic volcanoes that make fluid lava like in Hawaiʻi. Nonetheless, if the melted rock is way too fluid, it will behave far more like h2o and form droplets as a substitute. In Hawaiʻi these are acknowledged as Pele’s tears. The identical is real if the air is as well warm and doesn’t interesting the skin fast ample. If pulled aside much too swiftly the lava will not have adequate time to extend, and again it will break into parts. So, Pele’s hairs only kind below extremely specific problems, and the very best situations are in vigorous Hawaiian lava fountains or in effervescent lava lakes.
Scientifically, Pele’s hairs are portion of the tephra family that includes all strong particles flying out of a volcanic vent. The most common way to classify tephra is by grain sizing. For illustration, ash is outlined as tephra particles smaller sized than 2 millimeters (.079 inches), and lapilli is defined as tephra particles between 2 millimeters and 64 millimeters (.079 to 2.52 inches). The major tephra particles have two names. Tephra particles earlier mentioned 64 millimeters (2.52 inches) are called bombs if they are made from the freshly erupting magma, but they are identified as blocks if they are manufactured from preexisting rocks blasted by more explosive activity.
But what about Pele’s hairs? It appears to be a bit of a extend (pun meant) to phone them “bombs” even even though they are often a lot more than 64 mm (2.52 inches) long. Bombs or blocks usually tumble in the spot shut to the vent and pose a major hazard in that region. In 1924 a photographer that ventured much too close to the explosions from Kīlauea’s Halema‘uma‘u crater was fatally injured by a falling block. Pele’s hairs slipping on you would not do that. Instead, they travel with the wind like ash.
Pele’s hairs can spread much and are a regional hazard like ash particles, although the extensive flexible stands do not have the exact same aerodynamic attributes as tiny pieces of ash. This turns into a issue when hoping to forecast their whereabouts working with tephra dispersal types, so to classify them as ash also helps make little feeling.
Potentially Pele’s hairs are just unique. What other style of rock can curl up in mangled balls yet shatter from “bomb-size” to “ash-size” within a 2nd? So, make guaranteed to take pleasure in these interesting glass strands if you see them, but look at with treatment.
Volcano Activity Updates
Kīlauea is no for a longer period erupting. Its USGS Volcano Alert amount is ADVISORY.
Webcams exhibit no symptoms of lava action in Halemaʻumaʻu crater, at the summit of Kīlauea in Hawai‘i Volcanoes Countrywide Park. Summit tiltmeters have demonstrated numerous deflation-inflation occasions in excess of the earlier week. Seismicity is low. The sulfur dioxide (SO2) emission rate was most just lately calculated on February 28, when it totaled about 250 tonnes for every working day.
Mauna Loa is not erupting. Its USGS Volcano Notify Level is at Typical. Mauna Loa updates are issued on the 1st Thursday of the month.
Webcams show no indications of activity on Mauna Loa. Seismicity remains minimal. Deformation rates show inflation fairly over background stages, but this is not uncommon following eruptions. SO2 emission fees are at background stages.
There were being two earthquakes with 3 or far more felt reviews in the Hawaiian Islands throughout the previous week: a M2.6 earthquake 21 km (13 mi) SSE of Waimea at 21 km (13 mi) depth on March 17 at 11:22 p.m. HST, and a M3. earthquake 3 km (1 mi) SW of Pāhala at 35 km (22 mi) depth on March 20 at 6:26 a.m. HST.
HVO proceeds to intently watch Kīlauea and Mauna Loa.
Volcano Watch is a weekly post and action update penned by US Geological Study Hawaiian Volcano Observatory scientists and affiliate marketers. E-mail inquiries to [email protected]