Applicability of Vp-Vs technique in well log analysis for clastic reservoir in the Sirikit Oilfield | |
| Author | Chonticha Naralam |
| Call Number | AIT Thesis no.GE-16-13 |
| Subject(s) | Reservoirs. Predictive control. Engineering geotechnical. |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Geotechnical and Earth Resources Engineering with area of specialization in Geosystem Exploration and Petroleum Geoengineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. GE-16-13 |
| Abstract | n Thailand, there are both onshore and offshore oilfields. The greatest onshore is Sirikit Oilfield which provides the largest volumeofhydrocarbon among onshore oilfield. Sandstone interbedded with shale and shaly sandstone reservoirs have stored hydrocarbon for this oilfield. Although the Sirikit and oilfield inS1 concession supply the main HC ofonshore, there is still a need to search for some new HC sources to maintain or increase the reserve. Vp-Vs technique have been used for lithological and fluid identification recent years ago because acoustic wave velocity directly relates with elastic rock properties. In this study, Vp-Vs techniquewas used for lithological and fluid identification as well as TOC (total organic carbon content) estimation from multiple linear regression models in Sirikit Oilfield. Lithological and fluid identification by Vp/Vs was applied in well BH08 –09 where GR, NPHI, LLD,RHOB,DT, and DTS log data present, while TOC estimation by Vp/Vs was applied for well BH01 –02 where GR, NPHI, LLD, RHOB, DT, and geochemical data are available.Sonic velocities fromHC, brine, and shale zones, which are separated by GR and Vp/Vs methods, were calculated for elastic parameters consisting of Vp/Vsratio, elastic moduli, Poisson’s ratio, P-acoustic impedance (AIp), S-acoustic impedance (AIs), lambda*rho (λρ),and mu*rho (μλ). Six pairs of elastic cross-plots were constructed firstly. Clusters of HC, brine, and shale were separated clearly for well BH09, where only gas presents. Nevertheless, overlapping between the clusters was found. Thus, histogramanalysis was applied. Finally, the new cross-plots, Poisson’s ratio against λρ−μλ, was constructed. The results show that gas zone commonly provided steeper slope than oil, brine, and shale (mgas> moil> mbrine> mshale).Well BH08, slope of gas, oil, brine, and shale from K formation are 0.0088, 0.0046, 0.0033, and 0.0028. Well BH09, slope of gas, brine, and shale from Yom Formation are 0.0195, 0.0076, and 0.0062. Furthermore, cross-plots werealso applied for identifying three thin reservoirs. The results indicated the zones as oil reservoirs which corresponded with perforation intervals. Therefore, Vp-Vs technique could help to do for lithological zoning and fluid identification as well as thin reservoir identification successfully.Vp-Vs based methodfor TOC estimation, ΔlogR was used for the estimation both in well BH01 –02. TOC by ΔlogR closed to the measured TOC. Furthermore, level of maturity (LOM) was also calculated. LOM of the three shale zones from BH01 appeared in the range of gas shale, whiletwo shale zonesexpressed in the range of oil shale. Thus, the shale bed and source rock in the Sirikit oilfield are good gas/oil shale potential that can be explored/produced in future. |
| Year | 2017 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. GE-16-13 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Geotechnical Engineering (GE) |
| Chairperson(s) | Pham Huy Giao,; |
| Examination Committee(s) | Noppadol Phien-wej;Teekayu Benjawan; |
| Scholarship Donor(s) | Thailand (HM King); |
| Degree | Thesis (M. Sc.) - Asian Institute of Technology, 2017 |