Journal of Petroleum Research & Studies

Reservoir facies determination is the most important job in oil industry which dominantly relies on the major properties of rocks. Fundamental properties of rocks are usually understood by their detailed description in the field (lithofacies analysis) and laboratory (petrofacies analysis). The facies (lithofacies and petrofacies) determination in most subsurface studies is impractical, due to lack of cores and cuttings. In such situations, where the wire line logs are the only data available, the logfacies or electrofacies are determined instead. In this study, the available logs (gamma ray, density,Neutron, and sonic logs) for four wells (Am-1, Am-4, Am-5, and Am-6) were used to predicate logfacies of Khasib Formation in Amara oil field. Using Cluster Analysis in this study practiced the logfacies determination in each unit of khasib Formation in Amara oil Field using Interactive Petrophysics software. The types of input data into Interactive Petrophysics software to determine logfacies are available logs which are used to create 15 clusters and determine five groups of logfacies. In this paper, the vertical variations of logfacies for Khasib Formation are carried out based on five groups of logfacies. These groups of logfacies are classified based on responses of well logs after divided Khasib Formation into three units :( upper, middle and lower Khasib). In order to estimate the ratio of existence of logfacies, the histogram of logfacies was built for each unit of Khasib Formation in studied wells.

Nahr Umr oil field is one of the important productive southern Iraqi oil fields. This study focuses on the type of fold and faults of the Nahr Umr oil field. A structural analysis (geometric and genetic analyses) performed to identify its type, origin and to find its relevance to main regional tectonic events. The structural classifications employed well and geophysical data through using structure contour maps, cross sections, and seismic section.
The structural analysis inferred that fold of Nahr Umr oil field classified as antiform, upright, non-plunge, gentle, supratenous, dome feature, and asymmetrical. The limbs are unequal whereas the length of left limb shorter than the right limb and its dip is greater than right limb. In addition, the thickness of crest is less than the thickness of limbs. Pattern of faults classified as compound, parallel, conjugates and radial with graben structure and these faults concentrated on crest of fold. The fold axis is almost N-S at early cretaceous and then clearly turns to NW-SE and this may due to counterclockwise rotation of Arabian plate. Geophysical interpretations and results of structural analysis stated that Nahr Umr oil field formed by three combined forces which are tectonic movements, reactivated basement, and salt structures.

An Analysis of Variance (ANOVA) sensitivity analysis using suitable MATLAB code on the factors affecting oxides of Nitrogen (NOx) emissions of a hydrogen powered 4-stroke, water-cooled spark-ignition engine was conducted in this work. This was done using specialized engine performance and emission simulation software. The parameters studied were the engine speed, air-fuel equivalence ratio, spark plug location in addition to some other combustion parameters like combustion duration, heat loss besides some other useful performance parameters. It was found that NOx formation is minimum at peripheral spark location, slightly lean (PHI=0.9), and less advance timing is needed. Further, based on ANOVA analysis, the combination of engine speed and spark location has more significance (effect based on P-value) compared with engine speed and equivalence ratio. The combination of engine speed and ignition timing has more significance (effect based on P-value) compared with engine speed and equivalence ratio. Also found that NOx emissions behavior is more clear at lean mixture (PHI = 0.7), central spark location (XSP = 0.5) and retarded ignition timing (IGN near zero).

The oil drilling operations create large quantities of contaminated water known as “Produced Water”. The present study aims to treatment of produced water of the North Rumaila and Zubair oil fields, using stainless steel autoclave. A series of experiments were carried out at different conditions, temperature, pressure, acidity, revolution per minute (RPM) and salinity with and without flocculation .The result showed that 93% of oil was removed. An improvement was conducted when using surfactants.

Production logging is used to diagnose well production problems by evaluating the flow profile, entries of unwanted fluids and downhole flow regimes. Evaluating wells production performance can be easily induce from production logs through interpretation of production log data to provide velocity profile and contribution of each zone on total production. Production logging results supply information for reservoir modeling, provide data to optimize the productivity of existing wells and plan drilling and completion strategies for future wells. Production logging was carried out in a produce oil well from Mishrif formation of West Qurna field, with the objective to determine the flow profile and fluid contributions from the perforations after the stimulation job. The measurements were made under shut-in and three choke sizes (60/64”, 46/64” and 32/64”) flowing conditions.
Overall, the data quality is acceptable to generate a good analysis. From the flowing surveys, it was observed that just the intervals 2250-2285 m and 2335-2375 m are contributing to the total well production while the well was flowing through the chokes 60/64” and 46/64”. However, most production is coming from the interval 2250-2285 m for each choke.
The flow profile changed with the 32/64”, the interval 2250-2285 remained producing but the interval 2335-2375 m started receiving fluid from the upper interval. This cross flow increased after the well was shut in. The temperature log shows a normal behavior while the well is flowing through the 60/64” and 46/64” chokes, but changes as result of the cross flow with the 32/64” choke and with the well shut in.From the capacitance readings and pseudo fluid density (density from differential pressure) only oil is being produced, and there is a static water column at the sump.

In our study we have used several concentration of sodium chloride salts ( Nacl ) to test a tolerance of lime – treated mud prepared in laboratory in order to predict the conditions and amount of salt that may be occurred when we pass through salt formation or salty – formation as we have in Missan oil fields. We tried to show the effect of salt concentrations and variation of amount of lime on rheological properties of lime treated mud. Many samples were prepared for this goal. The main result of this study was, we can’t use this type of mud to drill the interval( lower Faris formation ) because of its pressure abnormality, but as an inhibitive acting lime treated mud appeared good properties to drill like this lithology with normal pressure.