Permeability simulation of two wells of one of the Iranian oil field reservoirs by three different methods mainly focused on concept of Fuzzy Logic.

Permeability values estimation using core-derived information of wells with just electric logs is an old problem in reservoir characterization. In essence, the problem consists in finding some explicit relation between log and core data in those wells that contain both types of information. Then, describe reservoir features (derived from core data) of other wells with log information only.Simulating accurate Permeability values is one the most crucial operations in Reservoir Engineering. Permeability is key parameter in determining the well completion strategy and the resulting productivity. These values obtain from the core data. Usually the wells with available core data are not sufficient to determine an accurate distribution of those petrophysical parameters. On the other hand, coring is a highly time and cost consuming operation in oil industry and the wells are mostly available with wireline logs information which is much more convenient and inexpensive to operate. Therefore, the challenge is to determine and estimate those petrophysical parameters needed to build a 3D reservoir model, based on the wireline logs only. Darcy is the fundamental unit of permeability in Petroleum Engineering, which is defined as: The permeability that is required to flow 1 cc/s of a fluid of 1 cp a distance of 1 cm through a cross-sectional area of 1 sq. cm. with a pressure drop of 1 atm. Note that the key word is ‘flow. Consequently, by definition the calculation of permeability must be dynamic.Applied fuzzy logic method usage for predicting Permeability values is the matter of this thesis. Fuzzy logic allows quantifying qualitative information and modeling complex not linear relations[5]. It invites the use of partial truths between the completely false and completely true alternatives and allows the consideration of the whole spectrum of possibilities between these alternatives. When it is applied to reservoir characterization, it accepts the premise that any interpretation is possible although some interpretations are more likely than others[1].

Keywords:

Permeability , Fuzzy Logic , Darcy , MLR method