Zonation of two oil reservoirs in Iran with a statistical method based on well log data


Different methods exist for the zonation of oil reservoirs based on petrophysical data and well logs. Among them are:
Permeability-Porosity cross polt, Pickett and Soder and Gill methods. In this study a statistical zonation technique has been used for the Marun and Pazanan oil reservoirs in Iran based on effective porosity, density, sonic, neutron and resistivity data.
Petrophysical interpretation of results can reveal the zones of high porosity, permeability and behavior of productive zones along the reservoirs. The present study used well log data (resistivity, neutron, density, sonic and radioactive logs) and Geolog software to obtain reservoir parameters such as porosity, water saturation, hydrocarbonic zones, lithology ana cut offs for the Marun and Pazanan oil fields.
Based on a variance analysis method, proposed by Testerman in 1962, a stasistical zonation was programmed and applied to the reservoirs parameters to obtain the best zones boundaries. The main advantage of this method is that the limits (or boundaries) of the different zones are determined automatically according to a condition which has been previously defined.