Petrophysical evaluation of formation damage in a miocene clastic reservoir in the Gulf of Thailand | |
| Author | Kongkiat Chaivarakitnan |
| Call Number | AIT Thesis no.GE-14-15 |
| Subject(s) | Oil reservoir engineering--Thailand, Gulf of Oil well logging--Thailand, Gulf of Oil wells--Thailand, Gulf of |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering 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-14-15 |
| Abstract | Formation damage is problematic issue for hydrocarbon exploration and production wells, since it causes the reduction in permeability. The consequence from formation damage can be minimized, if the problem can be detected early. Since well logging is done in the early stage, using well logging to identify formation damage would be useful. Each type of well logging tools have a different depth of investigation, where deep resistivity log may reads the virgin zone of formation, while other logs are more with the near wellbore zone. This uniqueness would be the key for identifying formation damage. The target of this study is a Miocene clastic reservoir in Pattani basin that locates in the Gulf of Thailand. The basin was formed since late Oligocene and its lithostratigraphy consists of 5 different sequences. The study area comprises of two wells: well A and B. From well logging interpretation, well A is found to contain 5 potential hydrocarbon reservoirs, where as there are 9 potential hydrocarbon reservoirs for well B. The reservoirs are slightly shaly - sand. The analysis of permeability models found that Morris and Biggs ’s model is suitable for permeability estimation in well A, where as well B is more suitable with Kozeny - carman’s model due to the better specific surface area estimation. The porosity estimation shows that the invaded zone poros ity (PHIDT, PHID) has the smaller value than PHILLd or virgin zone porosity due to the invasion of mud filtrate causing the formation damage. The estimation of filtrate invasion was found to be in the range of 8 to 20 inches deeper into the formation for well A, and in the range of 9 to 34 inches for well B. Mudcake permeability, wellbore radius, drilling pressure, invasion time, and porosity are the major parameters that influence the radius of filtrate invasion. The filtrate invasion also causes the reduction in the near wellbore permeab ility in the range of 80 to 90% lesser than the virgin zone permeability. The relationship between permeability of the invaded zone and that of virgin zone was found to have the exponential relationships. The correlations can also be used as a quicklook me thod for identifying the formation damage by observing the alteration between near wellbore and virgin zone permeability |
| Year | 2015 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. GE-14-15 |
| 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;Pinan Dawkrajai; |
| Scholarship Donor(s) | Thailand (HM King); |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 2014 |