Completion Optimization in the Bakken Petroleum System Using Data Mining

Therefore, the primary goal of this study was to identify optimal completion practices using publicly available well completion and production information and applying data-mining techniques that could accommodate nonlinear relationships.https://commons.und.edu/eerc-publications/1018/thumbnail.jp

Archie ve archie olmayan gözenek ortamdaki su saturasyon modellemenin çalışması

The aim of this thesis is to study water saturation models available in the literature and to apply a proper one to a real field case. Archie equation is the most well-known water saturation model. However, it is formulated on some assumptions and is applicable to only clean sands. Archie equation cannot be used for shaly formation. There are many shaly water saturation models that account for shale effect for water saturation estimation. In this study, 3 wells, namely Well-01, Well-02 and Well-03 are studied. These wells lie in a fractured carbonate reservoir located in Southeastern part of Turkey. From well log recordings, the production formation is seen almost clean. In other words, the shale amount of the formation is so small that it can be neglected. Thus, to calculate the water saturation in those wells, the well-known Archie water saturation equation is used. Since the formation is fractured carbonate, the cementation factor (m ) and saturation exponent (n ) of conventional value of أ2ؤ each cannot be used for the water saturation calculation. Instead, these parameters are obtained from generalized crossplot of log-derived porosity and resistivity technique. Finally, each well is divided into zones using porosity data. Zonation is conducted based on statistical method, ANOVA (analysis of variance). Well-01 and Well-02 are both divided into two zones. On the other hand, the statistical method was initially divided Well-03 into three zones. However, Well-03 is better described as a whole zone, depending on the geological analysis and engineering judgment. After the zonation, the zones are correlated from well to well. The water saturations in significantly correlated zones are examined. Also, using the same statistical method, the water saturation zones are identified. However, these zones do not coincide with the porosity zones. This difference is attributedM.S. - Master of Scienc

CO₂ depolamada örtü kayaç bütünlüğü.

One way to reduce the amount of CO2 in the atmosphere for the mitigation of climate change is to capture the CO2 and inject it into geological formations. The most important public concern about carbon capture and storage (CCS) is whether stored CO2 will leak into groundwater sources and finally into the atmosphere. To prevent the leakage, the possible leakage paths and the mechanisms triggering the paths must be examined and identified. It is known that the leakage paths can be due to CO2 - rock interaction and CO2 – well interaction. The objective of this research is to identify the geochemical reactions of the dissolved CO2 in the synthetic formation water with the rock minerals of the Sayındere cap rock by laboratory experiments. It is also aimed to model and simulate the experiments using ToughReact software. Sayındere formation is the cap rock of the Caylarbasi, a southeastern petroleum field in Turkey. The mineralogical investigation and fluid chemistry analysis of the experiments show that calcite was dissolved from the cap rock core as a result of CO2- water- rock interaction. Using the reactive transport code TOUGHREACT, the modeling of the dynamic experiment is performed. Calcite, the main primary mineral in the Sayındere is dissolved first and then re-precipitated during the simulation process. The decreases of 0.01 % in the porosity and 0.03% in permeability of the packed core of the Sayındere cap rock are observed in the simulation. The simulation was continued for 25 years without CO2 injection. However, the results of this simulation show that the porosity and permeability are increased by 0.001 % and 0.004 %, respectively due to the CO2-water-rock mineral interaction. This shows that the Sayındere cap rock integrity must be monitored in the field if application is planned.Ph.D. - Doctoral Progra

Sayindere cap rock integrity during possible CO2 sequestration in Turkey

One way to reduce the amount of CO2 in the atmosphere for the mitigation of climate change is to capture the CO2 and inject it into geological formations. The most important public concern about carbon capture and storage (CCS) is whether stored CO2 will leak into groundwater sources and finally into the atmosphere. To prevent the leakage, the possible leakage paths and the mechanisms triggering the paths must be examined and identified. It is known that the leakage paths can be due to CO2 - rock interaction and CO2 - well interaction. The objective of this research is to identify the geochemical reactions of the dissolved CO2 in the synthetic formation water with the rock minerals of the Sayindere cap rock by laboratory experiments. It is also aimed to model and simulate the experiments using ToughReact software. Sayindere formation is a regionally extensive cap rock for many oil fields in southeastern Turkey. The mineralogical investigation and fluid chemistry analysis of the experiments show that calcite was dissolved from the cap rock core as a result of CO2- water- rock interaction. Using the reactive transport code TOUGHREACT, the modeling of the dynamic experiment is performed. Calcite, the main primary mineral in the Sayindere is dissolved first and then re-precipitated during the simulation process. The decreases of 0.01 % in the porosity and 0.03% in permeability of the packed core of the Sayindere cap rock are observed in the simulation. The simulation was continued for 25 years without CO2 injection. However, the results of this simulation show that the porosity and permeability are increased by 0.001 % and 0.004 %, respectively due to the CO2-water-rock mineral interaction. This shows that the Sayindere cap rock integrity must be monitored in the field if application is planned

2-D Numerical Modeling of CO2 Storage in the Devonian H2S Containing Nisku Aquifer in the Wabamun Lake Area (Alberta, Canada)

AbstractThe Devonian Nisku aquifer has been identified as a suitable CO2 storage site in the Alberta Basin, but this aquifer contains significant amounts of H2S. Numerical simulations were performed to investigate the impact of dissolved H2S in the brine on the behavior of the injected CO2. No major differences in geochemical reactions were observed between model runs with and without H2S. Extensive dolomite dissolution was observed in both model runs, which caused a minor increase in porosity and permeability of the aquifer. The majority of the injected CO2 was trapped in the Middle Nisku as a free supercritical phase and the rest was dissolved in the brine

Pre-, Syn- and Post-CO2 Injection Geochemical and Isotopic Monitoring at the Pembina Cardium CO2 Monitoring Pilot, Alberta, Canada

AbstractGeochemical and isotopic data acquired pre-, syn- and post- CO2 injection at the Pembina Cardium CO2 Monitoring Pilot in Alberta, Canada is presented. To the author's knowledge this is the first project that has collected and interpreted comprehensive geochemical data over the full life cycle of a CO2 injection project. Of the 40 parameters measured per sample changes in pH, alkalinity, Ca2+, Fe2+, δ13C of CO2 and δ18O of H2O proved to be the most useful parameters as tracers of CO2 presence and for identifying solubility and mineral trapping in the reservoirs thus demonstrating CO2 retention mechanisms