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Recent investigations of the Laguna del Maule (LdM) volcanic field, central Chile, suggest the presence of a large, shallow, and active rhyolitic magma reservoir. Modest (up to~ 1.2 km3) rhyolitic eruptions over the last 20 kyr encircle an area inflating at an average rate of 25 cm/yr since 2007. 40Ar/39Ar, 14C, and tephra stratigraphy indicate that the majority of rhyolitic volcanism was concentrated in two phases (phase 1 and 2) separated by 9 kyr of repose. Here we report new petrological and geochemical results in order to determine if LdM rhyolites were issued from the same reservoir, identify the nature and timescales of processes leading to their eruption, and begin to relate the spectacular signs of unrest to magmatic processes. All LdM rhyolites are crystal-poor and contain phenocrysts of plagioclase, biotite and rare quartz. Major and trace element contents indicate most plagioclase crystallized in equilibrium …