Preliminary report on the 1963 eruption of Mt.Agung in Bali (Indonesia)

Mt. Agung in Bali which has been dormant for about hundred and twenty years showed increased activity on February 18 this year culminating with a paroxysmal eruption early in the morning on March 17; the second paroxysmal eruption occurred on May 16. The activity started with minor explosions in the main crater with the production of pyroclastics followed by the effusion of lavas which flowed over the lowest northern crater rim and the formation of nuées ardentes d’explosion which came down into the northwestern sector of the volcano. Successive nuées ardentes d’explosion which accompanied the paroxysmal cruption on March 17 and on May 16, came down along the southern, southeastern and northern slopes, devastating many villages. The first cycle of activity killed about 1700 people of which 1500 died from the nuées ardentes. Cold lahars, caused by heavy rainfall immediately after the eruption destroyed villages and constructions on the southern slope and killed about 200 more people. The nuées ardentes from the second paroxysmal eruption killed also about 200 more people who were all caught in the « Closed Zone ». A map showing the devastated area is presented.