Petrophysical properties of Mishrif Formation at the Tuba field determined from interpretation of open log data of(Tu-2,3,4,5,6,12,24,and 25) wells. These properties include total (effected) and secondary porosity, as well as moveable and residual oil saturation into invaded and uninvaded zones. According to Petrophysical properties it is possible to divided Mishrif Formation into three reservoir units (RU1,2,and 3) separated by four cap rocks (Bar1,2,3,and 4) . Three-dimension reservoir model is established by used (Petrel, 2009) Software for each reservoir units. Result shows that the second and third reservoir units represent important reservoir units of Mishrif Formation. Thickness and reservoir properties enhanced toward middle and

Mishrif Formation is the main reservoir in oil-fields (North Rumaila, South Rumaila, Majnoon, Zubair and West Qurna) which located at Basrah southern Iraq. The Inductively coupled plasma-Mass spectrometer (ICP-MS) was used for the water chemistry analysis and Scanning Electron Microprobe (SEM) for the purpose of mineralogy diagnosis. A weak acidic water of salinity six-time greater than seawater plays a role in generating the formation pressure and controlling the fluid flow. The potentiometric subsurface maps were modeled and the direction of super-pressure sites that are of a great importance in the oil exploration were marked to pay attention during future drilling.

The identification of a bed’s lithology is fundamental to all reservoir characterization because the physical and chemical properties of the rock that holds hydrocarbons and/or water affect the response of every tool used to measure formation properties. The main purpose of this study is to evaluate reservoir properties and lithological identification of Nahr Umr Formation in Luhais well -12 southern Iraq. The available well logs such as (sonic, density, neutron, gamma ray, SP, and resistivity logs) are digitized using the Didger software. The petrophysical parameters such as porosity, water saturation, hydrocarbon saturation, bulk water volume, etc. were computed and interpreted using Techlog software. The lithology prediction of Nahr

The aim of this study is interpretation well logs to determine Petrophysical properties of tertiary reservoir in Khabaz oil field using IP software (V.3.5). The study consisted of seven wells which distributed in Khabaz oilfield. Tertiary reservoir composed from mainly several reservoir units. These units are : Jeribe, Unit (A), Unit (A'), Unit (B), Unit (BE), Unit (E),the Unit (B) considers best reservoir unit because it has good Petrophysical properties (low water saturation and high porous media ) with high existence of hydrocarbon in this unit. Several well logging tools such as Neutron, Density, and Sonic log were used to identify total porosity, secondary porosity, and effective porosity in tertiary reservoir. For

Net pay is one of the most important parameters used in determining initial oil in place of a reservoir. It can be delineated through the using of limiting values of the petrophysical properties of the reservoir. Those limiting values are named as the cutoff. This paper provides an insight into the application of regression line method in estimating porosity, clay volume and water saturation cutoff values in Mishrif reservoir/ Missan oil fields. The study included 29 wells distributed in seven oilfields of Halfaya, Buzurgan, Dujaila, Noor, Fauqi, Amara and Kumait.

This study is carried out by applying two types of linear regressions: Least square and Reduce Major Axis Regression.

The Mishrif formation was

The detailed data of the Vp/Vs ratio and porosity logs were used to detect the Oil-Water Contact Zone (OWCZ) of Nahr Umr sandstone and Mishrif limestone reservoir formations in Kumiat (Kt) and Dujaila (Du) oil fields, southeastern Iraq. The results of OWC were confirmed using P-wave, Resistivity, and Water Saturation (Sw) logs of Kt-1 and Du-1 wells. It was found that the values of the oil-water contact zone thickness in Nahr Umr sandstone and Mishrif limestone were approximately one meter and eight meters, respectively. These results suggest that the OWCZ is possibly thicker in the carbonate rock than clastic rock formations. The thickness of OWCZ in the clastic rocks changed from one part to another, depending on several factors includ