Reservoir simulation phd thesis

However, amplitudes are only proportional to seismic reflectivity, which depends on the relative variability in the elastic properties of the formation, not on the value of these properties.

The detection of areas with significant changes or with unaltered hydrocarbon-indicative attributes can help determine drilling targets where hydrocarbons remain after several years of production.

They also provide relationships for the velocity and density of brine as a function of salinity, pressure and temperature See Appendix. A Scottish Enterprise Proof of Concept grant has recently been awarded to develop and commercialise a patented idea for prevention of CO2 leakage from geological reservoirs, which is considered a major risk for CO2 capture and storage.

The density-pressure relationships provide the pressure gradient within each phase and the entire pressure and fluid distributions can be integrated from the knowledge of the depth of the oil-water contact OWC and of one pressure value at one depth within the oil or gas zone. At the beginning of the increase in gas production relative to oil production indicates that gas started coming out of solution and that the reservoir pressure in the vicinity of the wells was below the bubble point The substitution of oil by gas exsolution updip is controlled by the pressure decrease induced by the producing wells see pressure drop in Figure 3. The research topics can cover wide range, from literature study via simulation to laboratory experiments. It is also proposed to investigate some of the challenges associated with sampling reservoir oils, such as the effect of mud filtrate contamination as well as the reversibility of asphaltene flocculation and re-dissolution, asphaltene deposition in reservoir rock, etc. However, amplitudes are only proportional to seismic reflectivity, which depends on the relative variability in the elastic properties of the formation, not on the value of these properties. Knowing the limits of any of the above relationships we have to determine which one could be used the most reliably and the most readily for the qualitative interpretation of the time-lapse impedances maps in an integrated 4D analysis. In addition to the perforated well intervals, the only flows allowed in and out the reservoir model are from eventual aquifers. Techniques combine direct visualisation studies of displacements at the pore scale with core-scale studies carried out under reservoir conditions. This formulation can be extended to a three phases medium [Zimmermann and King, , Chapter 2]. Differences in data acquisition, survey orientation, processing and quality of datasets can introduce significant noise in the 4-D analysis. They are all limited in application by the infinite number of parameters affecting the elastic properties of sediments and no approach can offer a comprehensive formulation.

One of the key parameters controlling the properties of oil is the bubble point pressure, which is the maximum pressure where free gas can be present.

Also, to quantify the amount of hydrocarbons responsible for the seismic differences, it is necessary to have a complete petrophysical model of the reservoir to establish a direct relationship between seismic attributes and pore fluids.

This formulation can be extended to a three phases medium [Zimmermann and King,Chapter 2].

Thesis reservoir

Pyrcz and C. Because the BHPs measured in the two wells after were below the bubble point, this indicates that the GOC has migrated down to at least these depths mbsf. All the parameters used for grain and fluid properties are given in Tables 1 and 2. Gow and S. Also, to quantify the amount of hydrocarbons responsible for the seismic differences, it is necessary to have a complete petrophysical model of the reservoir to establish a direct relationship between seismic attributes and pore fluids. The three primary types of pore fluid in a reservoir are hydrocarbon gas gas hydrocarbon liquid oil , and brine. He [] uses a constrained non-lineal inversion technique to estimate the acoustic impedance volumes from each 3D survey. Values of the grain moduli are given in Table 1. To relate quantitatively the observed changes in impedance with the nature and the volume of the pore fluids, it is necessary to have a complete representation of the sediment matrix, and to define the relationships between the different component of the system and its elastic properties. One of the standard indicators of fluid properties is the produced Gas-Oil ratio GOR , which is the ratio of the volumes of gas and oil produced at the surface. The fact that the impedances calculated after the reservoir sweep Fig 3. To illustrate the different steps of the entire procedure we use the case study of the K8 reservoir, South Timbalier , because of its relative simplicity. The research topics can cover wide range, from literature study via simulation to laboratory experiments. Hill, C.

After description of the reservoir simulator, the results of the simulation are finally used to generate impedance maps that can be compared with seismic inversions.

The lithology is expressed in terms of shaliness. This is shown clearly in K8 Figure 3.

If a complete PVT Pressure-Volume-Temperature analysis of the physical properties of gas samples is not systematically performed, the measure of its gravity is most often available and allows a good estimation of its properties as function of pressure and temperature [Batzle and Wang, ]. Islam, Petroleum Reservoir Simulations, Elsevier, In addition to the properties of the matrix, this requires to formulate also the elastic properties of the pore fluid, which are the primary parameters responsible for changes in impedance during production. Network modelling has also been used for to examine flow in biological systems flow in vascular beds. The coordinates and the attributes of the grid blocks porosity and permeability are directly imported from the reservoir characterization grid. The value of the bubble point and the relationships between pressure and elastic properties should be determined from PVT analysis of actual oil samples. Making sure that seismic differences are related to fluid flows is critical for a complete time-lapse seismic study. Assuming that the GOC and WOC have been simply sweeping uniformly along dip, and that the reservoir is still globally in hydrostatic equilibrium at any time, we have calculated as previously the pressure and fluid distribution that would exist in if an horizontal gas cap had formed down to mbsf and the WOC had moved up to mbsf. Fractured Reservoir Engineering Course content: Fracture detection and evaluation, Fractured reservoirs, case history, Physical properties of rocks, Logging versus fracture evaluation, Flow of fluids towards a well in non-porous fractured Rock, Flow towards a well in fractured rock of double porosity , Special problems of flow toward a well, Fluid displacement process in a single matrix block, Production mechanism of a fractured reservoir, Fractured Reservoir examples References [1] W. Results will be reported in bi-annual reports submitted to sponsors prior to Steering Committee meetings. Time-lapse analysis performed on seismic amplitudes has also been shown to allow the identification of migration pathways [He, ].

Network modelling has also been used for to examine flow in biological systems flow in vascular beds. It is suggested to start the project in June or as soon as 3 sponsors have confirmed their support.

In the latter case, the project scope will be revised based on priorities of the project sponsors. Due to the scale discrepancy the saturation profiles are too much averaged out, leading to unreliable production curves. Network modelling has also been used for to examine flow in biological systems flow in vascular beds. Procedure According to your major, get in touch with the contact person from the respective Chair: Drilling and Completion Engineering Petroleum and Geothermal Energy Recovery Reservoir Engineering Select a topic related to your major. Scope The actual scope of the project will be finalised based on the number of sponsors and their priorities. The bulk of the porosity is located immediately downdip from the two producing wells and in the South East corner of the study area. The detection of areas with significant changes or with unaltered hydrocarbon-indicative attributes can help determine drilling targets where hydrocarbons remain after several years of production. Management and reporting A Technical Steering Committee comprising of principal investigators and sponsors representatives will meet every six months to review progress, objectives and the future work programme. The three primary types of pore fluid in a reservoir are hydrocarbon gas gas hydrocarbon liquid oil , and brine. It is expressed in terms of daily production rate of oil or gas for each well, and averaged monthly. The formulas in the Appendix show that the density and the bulk modulus of gas mixtures increase significantly with pressure. Download