Later volcanic activity resulted in lava flows of dacitic composition being erupted along the ring fault of the caldera, as well as the formation of the resurgent dome by about uplift along the eastern caldera margin fault. This uplift encompasses both Galán ignimbrite rocks but also parts of the basement, the latter especially in the southern part of the dome. Post-caldera volcanism occurred on the northern margin of the caldera 2.01 ± 0.28 million years ago, and several small ignimbrites were emplaced after the main Galán eruption until less than 2 million years ago. These ignimbrites have similar compositions to the Galán ignimbrite and were formed from magma left over by the main Galán eruption. The onset of resurgence within the caldera may have been triggered by the same magma that is responsible for the post-caldera volcanism along the eastern caldera rims. The post-caldera volcanic systems appear to be rather ill-defined, however. The most recent activity was of tectonic nature and consists of movements along the faults and mafic volcanism farther west.