Pulsed neutron-neutron(PNN)logging is based on emitting neutrons into the near-wellbore zone and computing the neutron count decay due to scattering and capturing.The main application of this logging tool is to determ...Pulsed neutron-neutron(PNN)logging is based on emitting neutrons into the near-wellbore zone and computing the neutron count decay due to scattering and capturing.The main application of this logging tool is to determine the current oil saturation and to detect channeling in perforated and non-perforated intervals behind the casing.Correct interpretation of the results obtained from PNN logging enables engineers to predict new perforation intervals in depleted reservoirs.This study examines the application of PNN logging in a well located in one of Iranian oil reservoirs.The interpretation procedure is described step by step.The principle of the PNN logging and the specifications of the tool are discussed and the applications of PNN logging in evaluation of oil saturation,identification of water flooded zones and prediction of potential perforating zones are described.Channeling is also investigated between all layers,good and poor oil zones are characterized based on the calculated oil saturations and new perforation intervals are suggested with the aim to boost oil production from the reservoir.The results of this study show that zones 1 to 5 having low oil saturations,are interpreted as depleted oil zones.Zones 6 to 8 are interpreted as good oil zones having high potential to produce oil.Zone 9 is interpreted as a water zone.展开更多
The influence of carbonate formation on Pulsed Neutron logging(such as Pulsed Neutron-Neutron logging)is quite different from that of sandstone due to the complexity of reservoir architecture and the development of fr...The influence of carbonate formation on Pulsed Neutron logging(such as Pulsed Neutron-Neutron logging)is quite different from that of sandstone due to the complexity of reservoir architecture and the development of fracture in carbonate reservoir.To study the factors affecting Pulsed Neutron-Neutron(PNN)logging in carbonate formation,the responses on fracture or cave are simulated by Monte Carlo method,getting the relationships among the macroscopic capture cross section(Σ),the count ratio of the thermal neutron at far spacing and near spacing detectors(RATIO),the fracture porosity,oil-bearing and shale content of fracture.The results show that PNN logging can be used to detect caves,and there exist linear relationships among the macroscopic capture cross section(Σ),the count ratio(RATIO)and the above factors.The research findings in this paper provides theoretical basis for the interpretation and data correction of the PNN logging in carbonate reservoirs.展开更多
文摘Pulsed neutron-neutron(PNN)logging is based on emitting neutrons into the near-wellbore zone and computing the neutron count decay due to scattering and capturing.The main application of this logging tool is to determine the current oil saturation and to detect channeling in perforated and non-perforated intervals behind the casing.Correct interpretation of the results obtained from PNN logging enables engineers to predict new perforation intervals in depleted reservoirs.This study examines the application of PNN logging in a well located in one of Iranian oil reservoirs.The interpretation procedure is described step by step.The principle of the PNN logging and the specifications of the tool are discussed and the applications of PNN logging in evaluation of oil saturation,identification of water flooded zones and prediction of potential perforating zones are described.Channeling is also investigated between all layers,good and poor oil zones are characterized based on the calculated oil saturations and new perforation intervals are suggested with the aim to boost oil production from the reservoir.The results of this study show that zones 1 to 5 having low oil saturations,are interpreted as depleted oil zones.Zones 6 to 8 are interpreted as good oil zones having high potential to produce oil.Zone 9 is interpreted as a water zone.
基金Supported by Project of Sinopec Northwest Oilfield Branch(No.ky2019s023)
文摘The influence of carbonate formation on Pulsed Neutron logging(such as Pulsed Neutron-Neutron logging)is quite different from that of sandstone due to the complexity of reservoir architecture and the development of fracture in carbonate reservoir.To study the factors affecting Pulsed Neutron-Neutron(PNN)logging in carbonate formation,the responses on fracture or cave are simulated by Monte Carlo method,getting the relationships among the macroscopic capture cross section(Σ),the count ratio of the thermal neutron at far spacing and near spacing detectors(RATIO),the fracture porosity,oil-bearing and shale content of fracture.The results show that PNN logging can be used to detect caves,and there exist linear relationships among the macroscopic capture cross section(Σ),the count ratio(RATIO)and the above factors.The research findings in this paper provides theoretical basis for the interpretation and data correction of the PNN logging in carbonate reservoirs.