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Penyu Basin is a complex, intracratonic basin, situated on the northern Sunda Shelf. This basin formed during Oligocene, and geological setting of this area is a typical Southeast Asian Tertiary rift system. An oil discovery has been made in X-Block of Penyu Basin. However, it was relinquished in 2006 due to the non-commercial oil discovery. X-Block consists of mostly monoclinal structures that do not seem to provide an efficient trapping mechanism because of the very low reliefs. Three wells have been drilled in X-Block and tested primarily on the structural traps, mainly the basement drape structures. This research aims to analyze the stratigraphic traps, focusing on channel features. This is done with the aid from seismic geomorphology. This method helps examine buried landforms by using seismic data as a tool. By seismic geomorphology study, several channel features can be recognized. Most of the channels can be found in upper and middle part of the seismic section. As going deeper to the bottom section, only lineaments of faults are visible. In the upper part of the seismic section, straight and long channel features can be observed and as moving downwards, the channel sinuosity increases resulting in meandering channel. From this seismic geomorphology study, it confirms that there are channel systems in X-Block of Penyu Basin.

The Malay Basin early 2D seismic exploration programs were designed to test simple structural traps. Large relief folds are easily located and subsequently drilled. Many major oil and gas fields were discovered since the 1970s in middle-late Miocene siliciclastic reservoirs, and eventually produced successfully. However, these easy hydrocarbon accumulations in the Malay Basin are fast depleting due to its long production history. Hence, new petroleum plays are urgently needed to sustain the production. The utilization of high-resolution 3D seismic data in the early 2000’s has greatly increased the chance of drilling success, including high-risk prospects such as stratigraphic plays. This paper discusses the subtle channel morphology in the shallow section of the K Field. The 3D seismic data shows multiple-stacked channel geometry within the Pliocene (5.5-5.2 Ma) strata. The seismo-stratigraphic interpretation is aided by attributes analysis including horizon probe to detect and delineate the internal geometries. The results are correlated with modern analogues to predict the probable depositional elements within these fluvio-marine systems. These shallow channel features were previously avoided as hazardous drillings. Instead, until they are tested, these could be considered as good porosity clastic reservoirs filled by medium to heavy density oil.