Potential hazard scenarios from Taupo Volcanic Zone: Geological and historical record of large silicic systems (2020)
Type of ContentPosters
- Posters 
AuthorsCalderon, Rodrigo, Wilson, Thomas, Leonard, Grahamshow all
Taupo Volcanic Zone (TVZ) is a large silicic system capable of a diverse range of volcanic activity, thus includes multiple sources of hazard. Of these, an explosive eruption is the worst probable scenario, which includes the last known supereruption (over 1,000 km3 of volume) around 25 thousand years ago in Taupo caldera. Nowadays, in terms of volcanic activity, minor unrest could be the volcano peacefully stirring to shortly return to sleep, with not surface hazards, the same minor unrest could be a precursory signal of a major eruption, or fall somewhere on the spectrum between the two. This ambiguity increases the uncertainty in forecasting models. We need to be prepared. Fortunately, in term of hazards, high-silica (explosive) eruptions do not occur often based on geological and historical records. Unfortunately for scientific knowledge these records are scarce, and the associated deposits are usually heavily eroded. However, volcanologists strive to define compositional gradients of silicic magmas from rhyolitic deposits in different caldera volcanoes such as Long Valley, Yellowstone, Campi Fligrei, Novarupta and of course TVZ, among others. The Chaiten volcano in 2008, Chile, is a good case-study to understand silicic activity and their potential impacts, being the first scientifically monitored silicic eruption. Chaiten is a small (~ 3km diameter) caldera volcano located 10km to the north from Chaiten town, which was severely impacted by secondary lahars (volcanic mudflows that occur after the eruption has ended). This work is an effort to collect geological and historical records related to silicic systems and define a scenario framework for TVZ potential activity and impacts.