Giovanni Pezzati, Peter Burgess and Robert Hall


This study investigates the stratigraphic and structural history of Gorontalo Bay, Sulawesi based on multibeam and 2D seismic data. Recent studies by SEARG have identified Neogene to Recent metamorphic core complexes to the north and south of the basin, indicating rapid and significant exhumation which may be associated temporally and structurally with rapid and young subsidence in the bay itself.


Gorontalo Bay is a semi-enclosed sea between the North and East Arms of the K-shaped island of Sulawesi, eastern Indonesia. It is surrounded by land on three sides, separating a northern volcanic province from metamorphic rocks to the south and west, and ophiolites to the SE. New multibeam data collected in the basin show water depths of up to 2000 m in the western part of the bay. The narrow coastal shelf suggests rapid deepening of the basin. The recently active Una-Una volcano and multiple pinnacle reefs in deep water suggest crustal thinning and rapid subsidence in Gorontalo Bay.

Subsidence and uplift - multibeam