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Paleozoic sedimentary deposits are exposed in several locations on Peninsular Malaysia and may contain all the elements of a hydrocarbon system. Initial observations, mainly in the Kinta Valley, suggest the presence of source rocks, reservoirs and seals within the Paleozoic interval. The limestone hills of the Kinta Valley were the initial focus of this research project. The hills are remnants of extensive limestone beds, which are part of a very large Paleozoic carbonate complex that covered large parts of South-East Asia. The limestone beds are interbedded with sandstone, siltstone and carbonaceous shale over a thickness of up to 3000m.

A survey was carried out on a flat sandy land in the neighborhood of Gunung Datuk limestone hills complex. All 9 (NINE) boreholes drilled in this area encountered solid limestone rock at various depth ranging from 14.30 meters to 41.50 meters, indicating possible presence of karstic features. This report presents the result of 2D earth resistivity survey carried out in 2009 to provide a 3D subsurface view of the limestone head or karstic features which hopefully will help in designing the suitable foundation for any structure to be build here. Resistivity images clearly show that this area is a limestone area with karstic surface features, such as pinnacles and cavities. The depth of this zone is ranging from 8 to 35m. In some cases, some boreholes penetrated pinnacles, thus giving a false impression that the solid limestone is very shallow. In order to create a 3D subsurface view of the karstic limestone head, a total of 7 parallel lines were collected for each proposed site, and interestingly the results show, some of the proposed site were located directly above a possible collapsed cave (valley), thus special care need to be considered when designing the foundation of any structure to be build here structure.

The Miri Formation is a siliciclastic sequence consisting of a succession of coarsening upwards claysand packages where the sandstones form important oil reservoirs in the Baram Delta Province. The Middle Miocene Miri Formation, which crops out in the town of Miri in northeast Sarawak on and around the topographic feature called Canada Hill. The outcrops illustrate a complex structural geology and stratigraphy. Many authors on various aspects have studied these outcrops. However the definite stratigraphy and the structural model of the area comprising the Miri Oil Field are still questionable today.

The objective of this study is to model and establish a geological structure, mainly the basement rock, using potential field analysis. Two potential field methods, i.e. gravitational field and magnetic field were used in this study. The coastal margin sedimentary basin at Sungai Pahang Delta in Pekan, Pahang was chosen as the study site. This is to identify the basement rock structure due to delta development such as fault zone evolution, basement expansion and compaction. The data were interpreted both qualitatively and quantitatively. The qualitative interpretation is based on anomalies on the contour maps, and the quantitative interpretation is based on data modeling. There is good correlation between the gravitational and the magnetic field methods since the same features are found at the same locations. The result from the magnetic field method shows that the basement rock contains extended basalt intrusion. However, the gravitational data show a more localized intrusion and the presence of a metamorphism contact zone.