Geologists walk over the lava tube on the northern flank of Pu‘u ‘Ō‘ō
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Detailed Description
HVO geologists walk over the lava tube on the northern flank of Pu‘u ‘Ō‘ō while conducting a very low frequency (VLF) survey. Measurements are taken along a line of points (at flagged rocks) crossing perpendicular to the tube.