9614622 Voight The Merapi volcano in Indonesia is currently undergoing an active phase that is characterized by growth of a lava dome. Previously, this stage of lava dome growth has been followed by a phase of instability and collapse that resulted in the generation of hazardous pyroclastic flows as exemplified in the recent (1994) lethal dome collapse. The primary aim of this study is to shed light on the processes of dome growth and instability, fragmentation and pyroclastic flow transportation and deposition using the current cycle of activity at Merapi as a natural laboratory. The research proposed will comprise the key US component to the cooperative international research program developed during the Merapi Decade Volcano International Workshop, held in Yogyakarta last October. The work plan involves looking at deformation of the lava dome and effusion rates with a network of geodetic survey stations and telemetered tiltmeters; positioning rain gauges that will test the impact of storm precipitation events on pyroclastic flow occurrences; and conducting stratigraphic and textural studies of the 1994 deposits to provide constraints on the interior of the previous dome.
