Geophysical and petrologic studies of the Toba Caldera, north Sumatra

Rob McCaffrey, Dave Wark, Peter Zwick, Fauzi, Masturyono, Colleen Stevens, John Nabelek, Volcanological Survey of Indonesia, Meteorology and Geophysics Agency

Using 30 short-period and 10 broad-band PASSCAL seismographs, we monitored seismicity around Toba caldera for 4 months in early 1995. We produced tomographic images of the crustal and upper mantle structure using arrival time data and examined the velocity structure with receiver function methods. We are also analysing seismological data from global networks and from a local Indonesian seismic network in the vicinity of Toba Caldera.




Field Photos