a. In a word, it’s AMAZING! For a moment you can hold the newest piece of rock on the planet. Trying to scoop up some lava with a rock hammer is harder than it looks; its viscosity (resistance to flow) means it is surprisingly thick. It takes some effort to dig at it, and the heat emanating from even isolated lava flows makes it difficult to stand close to the lava for more than a few seconds at a time. Flowing basaltic lava has a temperature of about 1200°C, but it cools quickly when it’s exposed to ambient air. So quickly, in fact, that instead of forming a hard rock that you would normally imagine, the lava you scoop up with a rock hammer cools to a fragile (but pretty incredible) piece of volcanic glass.
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b. 360 Video: 50—active lava flow In order to reach the active lava flows in 2016, y2kcenter.org students embarked on a 3.5 mile hike along the coastline. The lava was coming from the Pu’u O’o vent on the East Rift Zone of Kilauea. The flows moved down the Pulama Pali, sometimes burning trees and are eventually entering the ocean. The flow was visible mostly in small outbreaks, but also in skylights to lava tubes and in larger streams. It is extremely hot close to even the small outbreaks. When approaching the outbreaks, glowing red lava is visible in cracks through the cooled crust (watch your step!). During the day, the active flows are difficult to distinguish from a distance because they look gray.
c. 360 Video: 56, 57—close to active lava flow The new lava flows are dark and very glassy at the surface. Lava that cools slowly forms crystals, but lava that cools very quickly forms glass. Because the air temperature (around 25°C) is so much cooler than the lava temperature (1000°C+), the lava at the surface cools very quickly into glass. The surface is very sharp, so the students were grateful to be wearing thick gloves and long pants for protection while hiking on the lava flows. After scooping up lava, the students ate dinner on the lava before going back to catch views of the lava at night.
Figures 1-4: On the 2016 y2kcenter.org Hawaii trip, we found this lava flow crossing an access road. Here, Matt Miller attempts the first scoop. A quick test with an infrared thermometer shows that the lava has already cooled to 650°C. Within minutes, it will be cool enough to touch.
Figure 5: Yes, it is, in fact, THAT exciting. Here, Matt Moody, Rachel Hampton, and Matt Luongo admire new samples.
Figure 6: Ginny Miller gets some help staying out of the lava flow.
Figure 7: Hannah Byrne, Maggie Powell, and Abba Parker show off a brand new rock.
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Figure 8: Neal Harrison demonstrates what not to do with lava.
Figure 9: Alicia Juang holds a piece of glassy lava. Note the strings of glass, called ‘Pele’s hair.’