Net Sand Determination or Facies Modeling for Development Geological Study (Lirik Field as Lesson Learning with 3D Application Software)



The Lirik Field is located in Japura Block, Central Sumatera Basin, 145 km to the southeast of Pakanbaru and 195 km to the northwest of Jambi. Geologically the Lirik Field is one of structures in Japura complex. This field was discovered in 1972 and the cummulative production at the end of 2006 is exceeding 40 MMBO with the remaining reserve of approximately 5 MMBO. Some problems such as high water cut and sand distribution were encountered in the effort of production optimation. This study is aimed to solve those problems by utilizing the available data using 3D Application Software. Sixty wells from the Lirik Field have been loaded into RMS. Most of these wells have Gamma Ray, SP, Induction and Density logs. Several methods have been implemented to determine the reservoir zonation and net sand thickness. This study was begin with sand body identification and facies zonation such as bar or channel sands in delta environment. The net sand thickness is a summation of all the permeable sands within the reservoir units or zones being studied. The permeable sand intervals within a zone can be indentified by using the induction and Gamma Ray or SP logs. Four zones in the Tualang Formation (H, J, K, and L) and four zones in the Lakat Formation (M1, M2, N, and O) have been identified from this study. The net sand thickness of each well can be calculated. To obtain a more realistic overview of the heterogeneity of facies distribution in the field, a 3D facies model was initiated and generated.


Author : Pande Made Oka Iriana, Okky Pahlevi