In March of 2015, twelve samples of vesicular basalt were collected from Villarrica volcano in Southern Chile. The samples were collected along a northeast-southwest trending fissure and cinder cone system on the east side of the stratovolcano, at nine locations. Samples were crushed, sieved, cleaned, and picked in preparation for ICP-MS (inductively coupled plasma mass spectrometry). ICP-MS data is used to determine the major and trace elements composition of the rock. We will use this geochemical data , so we can determine if these lava flows were sourced by a single eruptive event, or multiple eruptive events. Since these are mafic rocks, we are primarily going to be looking for significant differences in iron and magnesium content. Compositional analysis will also give us insight regarding magma source, and magmatic evolution. Hickey-Vargas et al., (1989), found that small satellite cones have higher olivine/plagioclase ratios compared to the lava from the main Villarrica volcano, so we expect to see something similar.
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Engstrom, Jordan, "Petrogenesis of Cinder Cones on Villarrica Volcano, Southern Chile" (2017). 2017 Undergraduate Research and Scholarship Conference.