The Characteristics of Volcanic Eruption in Indonesia

This chapter discusses the unique characteristics of the volcanic eruptions in Indonesia. We know that Indonesia has 147 volcanoes and 76 of them are active volcanoes and spread along the islands of Java, Lesser Sunda, Sumatra, and Celebes. The characteristics of Indonesian volcanoes are quite unique in terms of the formation process, eruption phenomenon, and the resulting natural disasters. Most volcanoes in Indonesia consist of stratovolcanoes, but this does not mean that the resulting eruptions are always explosive and they have a long period. This can be seen from the activity of Semeru that always erupts effusively every day, Sinabung that has a very short eruption period, Tangkuban Perahu eruption that occurs suddenly with the lack of early signs, and Merapi and Kelud that have eruption period that is getting shorter. Based on the results of our study it can be known that the types of volcanic eruption are influenced by the structure of the con - stituent rocks of the volcanoes. However, the presence of external control factors in the form of large-scale earthquakes will affect their periodicity. The large earthquakes can affect the stability of the magma chamber that can trigger a premature eruption.