TIDE-DOMINATED SHORELINE DEPOSITS IN THE NEOGEN SEQUENCE AT SEBATIK ISLAND, MALAYSIA

Sebatik Island belongs to two countries; Malaysia (northwest) and Indonesia (southeast). The study only involved Malaysia’s area, covering an area about 200 km2. The area of study comprised of Sebatik Sandstone-Shale Member from Kalumpang Formation; is part of the Neogene sequence located in the northern part of the Tarakan Basin. The main objective of this study is to analyze the sedimentary facies, and then to interpret the paleoenvironment in the study area. There has been no such study ever conducted by any researcher in Sebatik Island, Malaysia. This study was carried out through systematic characterization of sedimentary structure parameters on rock outcrops in the field based on sedimentological methods. Regarding on that characterization, several facies had been identified; amongst them namely heterolithic facies that was divided into three subfacies; lenticular bedding, wavy bedding and flaser bedding. These subfacies are combined and linked into one facies association that describe of the shoreline environments. It is formed through drag and drop processes dominated by the tides influence. The discovery on Sebatik Island, Malaysia is in line with the setting of Meliat Formation, Indonesia.