Open AccessAutomatic and Real-time Processing of Tilt Records for Prediction of Explosions at Semeru Volcano, East Java, Indonesia
Author(s) -
Hery Kuswandarto,
Muhamad Hendrasto,
Masato Iguchi
Publication year - 2016
Publication title -
kontribusi fisika indonesia
Language(s) - English
Resource type - Journals
ISSN - 0854-6878
DOI - 10.5614/itb.ijp.2008.19.3.2
Subject(s) - strombolian eruption , impact crater , tiltmeter , volcano , seismology , geology , tilt (camera) , explosive material , java , geodesy , magma , engineering , physics , astronomy , computer science , operating system , geography , optics , amplitude , mechanical engineering , archaeology
Eruptive activity of Semeru Volcano, East Java, Indonesia, is characterized by intermittent occurrence of strombolian and vulcanian types in intervals of 15 – 45 minutes. The explosive eruptions accompany explosion earthquakes and tilt changes of ground around the summit crater. Prior to the explosions (16 – 300 s before), gradual upward tilts of the crater side were detected with amounts of 0.3 – 20 nrad. The upward tilts turned to downward after start of explosive eruptions and tilt decreased by 0.7 – 50 nrad for 30 – 70 s. In order to detect the precursory tilt changes in real time automatically by using the tilt record, software coded by Visual Basic was developed. The software receives UDP packet data from A/D converter for the tiltmeter and shows the record on PC display. The software judge stages of volcanic activity (pre-eruption or eruption) based on the tilt change. In a test, 72% of increase in tilts prior to explosions was successfully detected.