Exploring magma composition variability at various tectonic settings, using global volcanic rock composition data with the DashVolcano tool

Abstract The relationships between plate tectonics, volcanoes, and the magma compositions they erupt are very important for understanding the whole-earth geodynamics. This requires the integration of global datasets from different sources and tools that allow us to visualize and access the data in an efficient manner, which is a challenging task. Here, we report a new version of the application tool called DashVolcano, which has linked the global record of all Holocene volcanoes from the Global Volcanism Program with the major element composition of erupted rocks from GEOROC and PetDB databases (~ 140,000 rock samples in total) according to tectonic settings. The tool allows us to visualize the volcanic rock names at a global scale with a map view and to plot their compositions using classical geochemical diagrams (Harker, TAS, AFM) for individual volcanoes or for a region of interest. Moreover, radar plots permit the visualization of the relative abundance of rock types per volcano or per region of interest and how they compare to various tectonic settings. Rock abundances can also be visualized according to the number of samples per volcano in order to better consider potential biases due to large differences in sample availability between volcanoes. The updated DashVolcano application allows us to explore a range of questions related to the abundance of erupted magma types in different tectonic settings, the differences in rock composition within or between chosen regions, volcanoes, and tectonic settings. DashVolcano should be a useful tool for research and teaching, and it is a good example of the challenges and opportunities of linking large databases at a global scale. DashVolcano is publicly available at https://dashvolcano.ipgp.fr/ .