Putana features active fumaroles, which generate a high plume above the volcano. This plume was seen as far back as the 19th century. The fumaroles have different shapes, from vents that are only centimetres wide to large wide openings. They occur in groups, in total four separate fumarole fields, two within the northeastern crater, one in the summit crater and one outside of the summit crater where about 30 individual fumaroles were reported in 1952. These fumaroles are visible as a thermal anomaly from space, but it is relatively weak with a temperature anomaly of only .