Integrated Approach for Characterizing Unconventional Reservoir Shale Hydrocarbon: Case Study of North Sumatra Basin

Southeast Asian Conference on Geophysics

Haris, A.^1 ; Seno, B.^1 ; Riyanto, A.^1 ; Bachtiar, A.^1

Master Program for Reservoir Geophysics, Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Indonesia, Depok

16424, Indonesia^1

关键词: Acoustic impedance inversion;    Geochemical analysis;    Integrated analysis;    Integrated approach;    Multi-linear regression;    Petrophysical analysis;    Total Organic Carbon;    Unconventional reservoirs;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/62/1/012023/pdf
DOI  :  10.1088/1755-1315/62/1/012023

来源: IOP

【 摘 要 】

Integrated analysis of geochemical, rock mechanic and geophysics were carried out to characterize and map the unconventional reservoir shale hydrocarbon in Baong field, North Sumatera Basin, which is proven with the large potential hydrocarbon, particularly in the sand reservoir. The new challenge of this field is the present of thick shale layer, which is offering the new concept of an unconventional reservoir. The shale layer has the double role as source rock and reservoir. In this work, we performed geochemical analysis on the core data to determine the Total Organic Carbon (TOC), mineralogy, Tmax, and Kerogen type. In term of rock mechanic, the Rock Strength was calculated to determine the hardness and brittleness index. While for petrophysical analysis, we performed multi-linear regression of log data to estimate TOC relationship with the seismic attribute. In term of geophysics, we carried out seismic inversion to produce acoustic impedance, which is useful to map shale distribution. Our analysis shows that the target of shale layer has TOC range from 2 up to 3.5 wt.% with brittleness index of 0.48. Based on the predicted Tmax, this shale layer is categorized into early mature phase and classified into II Kerogen type, which means it has a potential to produce oil. The shale layer was indicated by the result of acoustic impedance inversion which has a value for over 25000 ft/s ∗g/cc and Rock Strength less than 3000 Psi.