When will the next eruption take place? Examination of samples from Indonesia's Mount Merapi show that the explosivity of stratovolcanoes rises when mineral-rich gases seal the pores and microcracks in the uppermost layers of stone.
When will the next eruption take place? Examination of samples from Indonesia's Mount Merapi show that the explosivity of stratovolcanoes rises when mineral-rich gases seal the pores and microcracks in the uppermost layers of stone. These findings result in new possibilities for the prediction of an eruption.
Mount Merapi on Java is among the most dangerous volcanoes in the world. Geoscientists have usually used seismic measurements which illustrate underground movements when warning the population of a coming eruption in time.
An international team including scientists from the Technical University of Munich (TUM) has now found another indication for an upcoming eruption in the lava from the peak of Mount Merapi: The uppermost layer of stone, the "plug dome", becomes impermeable for underground gases before the volcano erupts.
"Our investigations show that the physical properties of the plug dome change over time," says Prof. H. Albert Gilg from the TUM Professorship for Engineering Geology . "Following an eruption the lava is still easily permeable, but this permeability then sinks over time. Gases are trapped, pressure rises and finally the plug dome bursts in a violent explosion."
Read more at: Technical University of Munich
This is the eruption of the Merapi on 11 May 2018. (Photo Credit: Université de Strasbourg/Uppsala University/Technical University of Munich/The University of Leeds/Universitas Gadjah Mada/German Research Center for Geosciences)
