 The magmatic system shallowed during this time, resulting in composition changes of the erupted ignimbrites and a general increase of elevations in the region.2.08 ± 0.02 million years ago the rhyodacitic Galán ignimbrite proper was emplaced.Aside from a facies that remained inside the caldera and is minimally thick, ignimbrites extend outside of the caldera to distances of but with an average runout distance of and have thicknesses of ; closer to the caldera it has been largely eroded away and there are more complete exposures farther away from Galán.