Mt. Merapi is one of the most active volcanoes in Indonesia, geologically is situated on the intersection of two faults of regional importance, namely the transverse fault which separates East Java from Central Java, and a longitudinal fault through Java which forms the boundary between the western Kendeng Ridge and the Ngawi sub Zone North of Simo.
As no satisfactoy scientific work has been completed to date at Dieng it is proposed that the scientific teams scheduled to work in Bali should be redirected immediately to Dieng. With the suggested programme, scientific work could continue through to December 1975 allowing the possible sitting of the first exploratory well by then.
Dalam rangka penelitian batuan gunung api purba G. Muria, penulis ditugaskan mendampingi tenaga ahli. Mereka adalah mahaguru Uniersitan Padjadjaran dan ITB.
Sebelum kejadian longsoran yang dimulai pada tgl 22 September, jam 15.00 turun hujan lebat dengan curah hujan yang tercatat di Plawangan rata - rata 83 mm per jam selama lk 3 jam. Longsoran diiringi awan panas hingga sejauh lk. 6 km kejurusan K.Batang dan Bebeng.