Various discussions have been made by many authors as respects the eruption mechanism of Krakatau caldera (e.g. Williams, 1941; Yokoyama, 1981; Self and Rampino, 1982; Yokoyama, 1982). Accumulation of geophysical data may provide important information to clarify the problem. Yokoyama and Hadikusumo (1969) have already established the gravity stations Krakatau Islands. The low residual anomalies…
The gravity survey on Krakatau Islands was first carried out by means of a land gravimeter in 1968 ( Yokoyama and Hadikusumo, 1969) and was supplemented by the present authors in 1982. The gravity points on the islands has reached 40 in number.
The author (1981) put an interpretation of the 1883 Krakatau eruption from the standpoint of geophysics. In the present paper, mainly the generation of the tsunami in the eruption will be discussed to supplement the previous interpretation.