After eruption of 1883, studies on the development or the recovery of natural ecosystem on the Krakatau Islands, especially those of vegetation and fauna, have been of great interest to many scientists. However, as far as we know, only a few studies on the soils were carried out (Ernst, 1908; Van Baren, 1931; Newsome, 1982).
Recent shallow seismic profilling survey by the Geological Research and Development Centre in cooperation with the Navy (AL) resulted in subsurface bottom sections which give for the first time an insight on the subsurface geology in the vicinity of the Krakatau-group (Akil and Lubis, S., 1983; Sukardjono, 1983).