3.2. Lava transport systems and emplacement
Processes related to lava transport and emplacement could be studied through thickness change maps (Fig. 3a–c) such as breakouts, inflation, lava stacking, pond formation, channel changes, deflation, cooling and contraction as well as vent changes. Especially, monitoring of inflation within valleys that were likely to spill into lower lying terrain was important since some sections of popular hiking trails were located below lava-filled valleys.
Despite the relatively stable effusion rate in phase 3 and 4 (Fig. 2), the braided lava pathways and the lava advancement were complex and variable as the lava filled and spilled from one valley into another. Short-term prediction of the timing of overflow from one valley to another provided challenges and thus monitoring the changes in the lava transport system and lava deposition in different valleys became important. The lava pathways were strongly controlled by the topography and mainly confined to the valleys and the steep slopes connecting them. However, since the valley systems consisted of multiple valleys east and south of the active vents the lava pathways were not uniformly filling up the valleys but switching from one valley to another. One way to monitor these changes and estimate the variability was to investigate the volume changes in different zones and vent distances (at 100 m interval) based on the thickness change maps. For each zone we could calculate the ΔV/Δt reflecting the volume deposited for a given period at a specific vent distance. This allows us to display the changes in lava transport and deposition in between these zones and distances over time (Fig. 3d).