a. So, maybe you haven’t thought about it. But after you see how quickly lava cools when exposed to air, you may wonder how some of the lava flows on Hawaii managed to travel for tens of miles before cooling. Most long flows self-insulate by forming lava tubes that allow the lava to remain hot and flow further.
b. 360 Video: 25—Thurston Lava Tube entrance (8/18/16) Thurston Lava Tube is just one of many lava tubes that have transported lava away from volcanic vents. Lava tubes are distinct from dissolution caves, which form from the removal of material. Lava tubes form during eruptions as the top surface of a lava flow cools more rapidly than the underlying lava, forming a crust. The crust insulates the lava underneath, allowing it to stay hotter and flow further. A lava tube cave is left behind when the lava drains. Collapses in lava tubes create skylights, like the one through which visitors enter Thurston Lava Tube.
Figure 1: Thurston Lava Tube, in Hawaii Volcanoes National Park, is well-lit and large enough for visitors to walk through.
Figure 2: EPS students descend into Kaumana Cave, a lava tube near Hilo, Hawaii in August 2016.
Figure 3: After making their way through a dark lava tube with headlamps, students enjoy a skylight in Kaumana Cave.