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Noble gas raw data for the Hawaiian islands of Big Island, Maui, Oahu, Lanai, and Kauai. The noble gas helium is used as an indicator of geothermal heat when excess 3He and/or 4He is present when compared to the atmospheric ratio of those isotopes (R/Ra). R/Ra anomalies are present on every island in this study. There is a strong correlation between R/Ra anomalies and proximity to rift zones and calderas. Across the islands R/Ra ranged from 15-16 on Kīlauea’s lower east rift zone, which is a mantle plume value, to 0.37 on Lāna‘i, which is a crustal value. The majority of anomalous well samples had R/Ra values consistent with an upper mantle source. Mixing between upper mantle and crustal helium is evident on all islands. Geographically, R/Ra decreases from the high at Kīlauea to upper mantle values at Mauna Loa, and remains at upper mantle values for all wells across the other volcanoes, with the exception of two of four sampled wells on Lānaʻi, which have radiogenic, crustal R/Ra values. |
https://gdr.openei.org/files/1373/Noble%20Gas%20Raw%20Data.xlsx |