Fig. 6
From: In-situ monitoring of 3He/4He in summit gases of Kilauea Volcano (Hawaii) prior to the 2020 eruption
Timeseries of 3He/4He as R/RA and RC/RA ratios from the December 2020 deployment, with significant events marked. Except as noted, RC/RA for the instrument and conventional samples are plotted versus the collection date. Sample type is depicted by the symbols (see legend). All data from Tables 1 and 2 as well as the Dec. 15th 3He/4He fumarole data (USGS, A. Hunt, analyst) provided by T. Nadeau (pers. comm., 2021). Estimated 0.5 RC/RA errors are assigned to the HIM data reported in Table 1; other errors are from values reported in Table 2 or are within the symbols