| Author | Wattanaporn Phaophongklai |
| Call Number | AIT Thesis no.OTM-10-05 |
| Subject(s) | Oil well logging--Thailand, Gulf of
|
| Note | A thesis submitted in partial fulfillment of the requirements for
the degree of Master of Engineering in Offshore Technology and Management, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. OTM-10-05 |
| Abstract | Jasmine is one of oil fields in the Gulf of Thailand. It is located in the B5/27
Block, in the northern part of Pattani basin. The depositional environment in the area
is lacustrine interbedded with fluvial of non-marine sediment.
The water saturation (Sw) is one of the key issues, which is needed to be taken
into consideration for in oil field development & production. As reported by quick
look interpretation of Pearl oil, the water saturation Sw of Jasmine field was
overestimated by using Archie’s equation, which is mainly used for clean sand
formation. This overestimation of water saturation might be due to the fact that the
reservoir sands at the Jasmine field are not clean sand, but shaly , consequently we
need to find better methods to calculate Sw. This study is conducted in order to obtain
the more realistic Sw by using various equations to calculate Sw, e.g., Simandoux,
Indonesian, Dual and Waxman-Smith for case of shaly formation.
The selected well for the study is located in the northern flank of the Pattani
basin. Acquired well logging data used for the study are gamma ray, resistivity,
neutron and density logs. By well logging interpretation 13 zones were identified as
reservoir zones, mainly based on gamma ray, resistivity, neutron and density logs.
Shale volume (Vsh) was then determined based on gamma ray logs. The porosity was
calculated based on density log. An emphasis was placed on determining the shale
type of the reservoirs. The shale types were determined using Thomas-Stieber plot
method and it was found that the predominant type of shale in most reservoirs zones
is dispersed; a result number of reservoir zones are clean sand and have structural
shale. An important parameter in estimation of water saturation is the water
resistivity, which was well studied using Archie’s law and Pickett plot. The water
resistivity was found to be around 0.6 Ωm. The estimation results of water saturation
based on Archie, Simandoux, Indonesian, Dual and Waxman-Smit, respectively are
summarized in Table 4.6. The most optimistic Sw was obtained by using Indonesian
equation; in contrast the most pessimistic Sw is derived from Archie equation. The
permeability of the reservoirs was estimated based on the permeability – porosity
relationship of core data.
In conclusion, a methodology to evaluate the shaly formation was successfully
applied and could help solving the problem of high water saturation at the study oil
field. It is recommended to be applied for interpretation of other wells in the field. |
| Year | 2010 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. OTM-10-05 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Offshore Technology and Management (OTM) |
| Chairperson(s) | Pham Huy Giao |
| Examination Committee(s) | Chiu, Gregory L.F.;Park, Kyung-Ho |
| Scholarship Donor(s) | Pearl Oil (Thailand) Ltd. |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2010 |