PDF file - Laboratoire de Géologie de l'Ecole normale supérieure - Ens

MICROBLOCK ROTATIONS IN SULAWESI, INDONESIA
Figure 2: GPS velocities of Sulawesi and surrounding sites with respect to the Sunda Plate. Grey arrows belong to the
Makassar Block, black ones to the northern half of Sulawesi and white ones to non-Sulawesi sites (99% confidence
ellipses). Numbers near the tips of the vectors give the rates in mm/yr. The main tectonic structures of the area are
shown as well.
continuation of the Sula-Sorong Fault [Hinschberger, et
al., 2000]) which continues to the Palu–Koro Fault in the
north, which then connects to the Minahassa trench
where subduction occurs (Figure 2). The Gorontalo
strike-slip fault cuts the northern arm of Sulawesi and
may connect to the Minahassa trench. At the Eastern
termination of the Minahassa Trench, the Sangihe double
subduction zone accommodates convergence between the
3
Philippine Plate and Sulawesi across the Molucca Sea
(Figure 2).
The main active structure in Sulawesi is the Palu-Koro
fault and its southeast continuation to the Matano fault
and/or Lawanopo fault. The Palu-Koro fault bisects the
island: the Makassar block on the southwest and the North
Sula block on the northeast. GPS shows that the total
motion across the fault is around 4 cm/yr. If this slip