TephraKam: geochemical database of glass compositions in tephra and welded tuffs from the Kamchatka volcanic arc (northwestern Pacific)

Abstract

Tephra layers produced by volcanic eruptions are widely used for correlation and dating of various deposits and landforms, for synchronization of disparate paleoenvironmental archives, and for reconstruction of magma origin. Here we present our original database TephraKam, which includes chemical compositions of volcanic glass in tephra and welded tuffs from the Kamchatka volcanic arc. The database contains 7049 single-shard major element analyses obtained by electron microprobe and 738 trace element analyses obtained by laser ablation inductively coupled plasma mass spectrometry on 487 samples collected in close proximity to their volcanic sources in all volcanic zones in Kamchatka. The samples characterize about 300 explosive eruptions, which occurred in Kamchatka from the Miocene up to recent times. Precise or estimated ages for all samples are based on published 39Ar∕40Ar dates of rocks and 14C dates of host sediments, statistical age modeling and geologic relationships with dated units. All data in TephraKam are supported by information about source volcanoes and analytical details. Using the data, we present an overview of geochemical variations in Kamchatka volcanic glasses and discuss applications of these data for precise identification of tephra layers, their source volcanoes, and temporal and spatial geochemical variations in pyroclastic rocks in Kamchatka. The data files described in this paper are available on ResearchGate at https://doi.org/10.13140/RG.2.2.23627.13606 (Portnyagin et al., 2019).