Sanudin Tahir

Tectonic evolution of the Marudu Bay, Sabah, Malaysia

Abstract The Marudu Bay is engulfed by the Kudat and Bengkoka Peninsulas, in northern Sabah. A detailed geological study has been carried out to differentiate the stratigraphic sequences of the area which in ascending order are: Chert Spilite Formation, Crocker Formation, Kudat Formation, South Banggi Formation and Timohing Formation. Igneous rocks, especially serpentinite are also found randomly distributed in the study area. A major structural pattern of the area shows that several episodes of deformation have taken place. A few types of folding such as asymmetrical to recumbent folds with different axial positions have been identified. The movements between Philippines, Eurasian, Pacific and Indo-Australian Plates have strongly affected the geology of the northern area of Sabah since Late Cretaceous. Some comparisons between the Kudat and Bengkoka Peninsulas such as rock boundaries and structures show that the marudu Bay has undergone rifting due to clockwise rotation since Middle Miocene.