Study of Petrophysical properties of mishrif and yamama formations at selected fields, South Iraq

Abstract EN

The characteristics of reservoir require reliable knowledge of certain fundamental reservoir properties.

Log measurements can define or at least infer these properties : resistivity, porosity, shale volume, lithology, water saturation, hydrocarbon saturation and permeability.

The current study represents evaluation of petrophysical properties in wells Fa-1, Fa-2 and Fa-3 in Faiha oilfield and in well Snd-2 in Sindibad oilfield of Mishrif and Yamama formations, southern Iraq.

The petrophysical evaluation was based on well logs data to delineate the reservoir characteristics of Mishrif and Yamama formations.

The available well logs such as (Gamma ray, SP, Resistivity (MSF, ILL), Sonic, Density and Neutron logs) are digitized using Didger software (v.4).

The environmental corrections and petrophysical parameters such as porosity, water saturation, hydrocarbon saturation and shale volume were computed and interpreted using Interactive Petrophysics software (IP).

Petrophysical properties were determined and plotted as computer processing interpretation (CPI) using Interactive Petrophysics software.

Lithological study of Mishrif Formation appears that it consists mainly of interbedded limestone, dolomite and shale, whereas lithological study of Yamama Formation appears that it consists mainly of interbedded limestone, dolomite and shale in some depths.

Interpretations of well logs of Mishrif Formation in well Snd-2 it have good hydrocarbon saturation.

Results also referred that hydrocarbon saturation and permeability in some ranges of the formation especially in MB unit is very high, in addition to the low movable oil and this may indication of the heavy oil in the formation.

While interpretations of well logs of Yamama Formation in well Fa-1 indicated high hydrocarbon saturation.

In general, the reservoir characteristics of Yamama Formation in Fa-1 are better than wells Fa-2 and Snd-2, and reservoir characteristics of Mishrif Formation in well Snd-2 better than Fa-1 and Fa-3 according to petrophysical properties and hydrocarbon saturation.

Mishrif Formation in Faiha oilfield is divided into nine zones and nine zones in Sindibad oilfield, while Yamama Formation is divided into six zones in Faiha oilfield and seven zones in Sindibad oilfield according to Behavior of well logs and Shale volume.