The 72 sandstone is one of potential reservoir in the South Sembakung field, which is located in the Tarakan Basin, within the Simenggaris Production Sharing Contract between Pertamina, Medco E&P and Salamander.The aim for this study was to characterize the reservoir in terms of log patterns, porosity, quality and depositional environment, and to establish the distribution of the reservoir in the South Sembakung field. The data used for the study of 72 reservoir sandstone are mainly logs, core and seismic data.
The 72 reservoir is characterized by a blocky to bell-shaped fining upward log pattern, fine to medium grained sand with fair to good porosity and permeability. The sands are well sorted and have common cross bedding with occasional carbonaceous laminae with scattered burrows. The reservoir thickness is in range of 10 to 60 feet.Based on the result of analyses, it can be summarized that the 72 sandstone as deposited in the tidal deltaic setting and the channel facies which shows an approximate east to west trend.
Authors : Tulus Wibisono, Erwin Muhamad Indra Kusumah, Selly Selfina Bella, Iantony Adrianus Siregar, Adhi Wicaksono