Data Publication

Major elements geochemistry of Pico Cabras dome’s explosive and effusive products (Tenerife) [Dataset]

Dorado, Olaya | Andújar, J. | Martí Molist, Joan | Geyer, Adelina

Digital.CSIC

The dataset contains all the chemical data collected for the work “Mechanisms controlling explosive-effusive transition of Teide-Pico Viejo dome eruptions”. The samples were taken from Pico Cabras dome (Tenerife), including deposits of the sub-plinian fallout (explosive phase) and the lava flow and dome (effusive phase). The samples were analysed with a SEM Merlin Compact ZEISS with an EDS Bruker detector (QUANTAX-XFlash6-30mm2-129eV) at the ISTO Measures Physiques laboratory (CNRS, Orleans). Additionally, we performed a micro-XRF analysis using the XTRACE detector (Tube Rh – filtres Al, Ti, Ni) connected to the MEB, which was calibrated against inner Br glassy standards containing different amounts of Br (Faranda et al. 2019) in order to analyze Br in sodalite and glass in the pumice samples. Mineral phase compositions were obtained with an electron microprobe SX-FIVE, also at the ISTO. An acceleration voltage of 15kV, a sample current of 6nA, and a counting time of 10s were used. For the glasses, a defocused beam of 10μm and 20μm was used, whereas for minerals a focused beam was employed. Whole-rock data was obtained by analysing two glass samples resulting from the two-step melting (with grinding in between) of lava and pumice samples at 1400ºC for 4 hours in total time, respectively. The aim of the study was contributing to the understanding of the mechanisms that control the transition between explosive and effusive dynamics in dome-forming eruptions at T-PV stratovolcanoes and propose a conceptual model for the magmatic reservoir of Pico Cabras prior to eruption. In this dataset we collect all de geochemical data obtained in the study. The Excel file consists of seven sheets, each one corresponding with one of the principal phases found in the samples: feldspars, pyroxenes, biotites, magnetites, ilmenites, sodalites and glasses (including the whole-rock analysis resulting from the obsidian obtained in the melting of the samples). The four analysed samples were given a International GeoSample Number (IGSN) for their correct identification. IEODG0001, IEODG0002 and IEODG0004 are samples from the effusive phase of Pico Cabras dome eruption (the later corresponding to an obsidian sample from the dome itself). IEODG0003 are pumices samples from the explosive phase in which minerals and glass fragments were selected for analysis.

Keywords