UNLOCKING HETEROGENETIC RESERVOIR BY USING SEQUENCE STRATIGRAPHY ON SANDY FLUVIAL DEPOSITS OF THE MIDDLE BALIKPAPAN FORMATION OUTCROP, SAMARINDA, KUTEI BASIN; IT’S IMPLICATION FOR RESERVOIR DISTRIBUTION

• Main Authors: Rizki Putra Ptratama, Rizki Putra Ptratama, Diponegoro Ariwibowo, Diponegoro Ariwibowo, Zakaria Yahya, Zakaria Yahya
• Format: Article PeerReviewed
• Language: English
• Published: Departmen Teknik Geologi 2015
• Subjects: Geology
• Online Access: https://repository.ugm.ac.id/135514/1/GEO118%20Paper%20Semnas%20UGM%202015%20STT%20Migas.pdf; https://repository.ugm.ac.id/135514/
• Institution: Universitas Gadjah Mada

Basically, Sequence stratigraphic concept has used for analyses of seismic cross- sections, well logs and outcrop studies of sedimentary rock are used to predict the thickness, extent of sediment lithology and understanding sediment geometry changes with relative sea level and rates of sedimentation. The sequence principles can be applied readily to outcrop sources. This paper will fully discuss the sequence stratigraphic concept of heterogenetic facies on Gelingseh formation (Balikpapan Group). The data were collected from the surface outcrops in Simpang pasir area, Samarinda through field geology mapping. Then we continued to a laboratory analysis of said Miocene outcrops within study area. Several individual facies, in terms of deposition events, were determined in the study area. There are 8 facies associations from four stratigraphic logs: 1) Pebbly – Very Coarse Grain Sandstone (Gradding Oriented), 2) Fine Grain Size – Medium Grain Size Massive Sandstone, 3) Massive Mudstone (Shale Clast), 4) Massive Mudstone (Silt Clast), 5) Fine Grain – Coarse Grain through cross bedding Sandstone, 6) Fine Grain – Medium Grain Mud Drapes Associate Cross Lamination Sandstone, 7) Fine Grain – Medium Grain Laminae Sandstone, 8) Coal Seam. According to the integration of all the individual beds, an analysis of the vertical stratum succession, with nearly complete sequences, are observed at the outcrops in the study area. This study has interpreted comprehensive sand deposits in a fluvial deltaic, which will be useful to encourage future exploration and development.