Characteristics and Consequences of Volcanic Gas from Mount Merapi towards Human Health and the Surrounding Environment

Mount Merapi is located in 4 Indonesian regencies: Sleman, Magelang, Boyolali and Klaten. A stratovolcano, Mount Merapi is one of the most active volcanoes worldwide. The largest eruption at Mount Merapi occurred in 2010 and claimed 347 lives with an explosive nature and a Volcanic Explosivity Index (VEI) of 4. The method used in this research was the Giggenbach method for chemical gas analysis. Based on results from monitoring Mount Merapi since its last eruption in 2010, there has been a decline in its activity. Based on the topographical map of the Mount Merapi zone released by the Indonesian National Agency for Disaster Management, there are 38 villages located in the volcano danger zone. Among them are Desa Kaliurang, Desa Tegalmulyo, and Desa Balerante. Therefore, the purpose of this research is to determine the effects of volcanic gas from Mount Merapi's eruptions on those living nearby. Based on the results of chemical gas analysis from Mount Merapi 1 in 2015 by the Geological Agency of the Ministry of Energy and Mineral Resources, the volcanic gas consisted of 12.98% O-2+Ar, 51.20% N-2, 8.20% CO2, 0.18% HCl, 0.29% NH3, and 27.15% H2O. At Mount Merapi 4, the gas was composed of 11.29% O-2+Ar, 43.93% N-2, 0.02% CO, 1.75% CO2, 0.13% HCl, 0.22% NH3, and 42.66% H2O. This research concludes that the gaseous chemical substances released during Mount Merapi's eruption are extremely dangerous for human health and have potential to damage the surrounding environment.