The intensity of eruption at Kerinci varied during April and May. White or gray ash plumes rose up to 700 m above the summit on many days during these months. Periodic increases and decreases in both volcanic and tectonic earthquakes were recorded.

In June the number of daily volcanic earthquakes increased and the ash erupted from the summit became darker in color. During the week of 22-28 June, volcanologists noticed that the ash column rose 600 m above the summit under strong gas pressure and that the summit topography changed. On 28 June tremor became continuous and at 0630 on 29 June an ash column rose 1,000 m above the summit under strong gas pressure. Increased ash emissions and nearly continuous tremor continued for several weeks.

Two eruptions of dark brown and black ash rose 800 m above the summit on 21 July. Black ash was vigorously ejected on 23 July. The ash from this eruption drifted eastward in a billowing cloud. Ash erupted on 28 July fell on nearby villages and farms. During August activity slowly decreased in intensity: tremor resumed normal levels and periods of duration, and emissions were a more normal dense white color. Eruption plumes rose to heights of 100-500 m. This calmer activity persisted through September.

Geological Summary. Gunung Kerinci in central Sumatra forms Indonesia's highest volcano and is one of the most active in Sumatra. It is capped by an unvegetated young summit cone that was constructed NE of an older crater remnant. There is a deep 600-m-wide summit crater often partially filled by a small crater lake that lies on the NE crater floor, opposite the SW-rim summit. The massive 13 x 25 km wide volcano towers 2400-3300 m above surrounding plains and is elongated in a N-S direction. Frequently active, Kerinci has been the source of numerous moderate explosive eruptions since its first recorded eruption in 1838.

Information Contacts: Volcanological Survey of Indonesia (VSI), Jalan Diponegoro No. 57, Bandung 40122, Indonesia (URL: http://www.vsi.esdm.go.id/).