A reservoir in payrock in analysed using finite element simulation. A reservoir engineer selects an appropriate model from a set of template models, each including a set of polygons in plan and layers in elevation. The polygons are defined in objects instantiated from classes by control points and the layers as depth values of control points. A pattern object sweeps rotationally about a wellbore in a wellbore polygon to define a pattern of elements, fewer in number with distance from the wellbore. A polygon object also sweeps linearly from a generator line in the direction of a base line. The generator and base lines correspond to polygon boundaries. Finite element simulation is performed with the model so derived.

A method is provided for evaluating the performance of a plurality of oil wells which were established to produce from a common reservoir beneath the earth's surface. The method comprises inputting information about the reservoir into a computer and establishing a time interval and time steps within that time interval over which performance of the wells will be evaluated. The total oil which is accessible clearing each time step in each time interval is determining, and then individual recovery factor for each time step is determined. A composite recovery factor is determined using the individual recovery factors, and the composite recovery factors are normalized to the best well in the field.

An overall petroleum reservoir production optimization methodology permits the identification and remediation of unstimulated, under-stimulated, or simply poorly performing reservoir completed intervals in a multilayer commingled reservoir that can be recompleted using any of various recompletion methods (including but not limited to hydraulic fracturing, acidization, re-perforation, or drilling of one or more lateral drain holes) to improve the productivity of the well. This provides an excellent reservoir management tool and includes the overall analysis and remediation methodology that has been developed for commingled reservoirs. The specialized recompletion techniques can be used to improve the productivity of previously completed individual reservoir intervals in a commingled reservoir.

A method for providing production optimization of reservoir completions having a plurality of completed intervals via available production analysis and production logging data provides a quantitative analysis procedure for reservoir and fracture properties of a commingled reservoir system, that includes the steps of measuring pressure for specific zones in a reservoir; selecting a pressure traverse model; computing midzone pressures using the traverse model; comparing the computed midzone pressures with the measured pressures; and modeling the bottomhole pressure of the reservoir based on the traverse model.

A method for enhancing allocation of fluid flow rates among a plurality of wellbores coupled to surface facilities is disclosed. The method includes modeling fluid flow characteristics of the wellbores and reservoirs penetrated by the wellbores. The method includes modeling fluid flow characteristics of the surface facilities. An optimizer adapted to determine an enhanced value of an objective function corresponding to the modeled fluid flow characteristics of the wellbores and the surface facilities is then operated. The objective function relates to at least one production system performance parameter. Fluid flow rates are then allocated according to the optimization.