This research involves the study of permeability declination as a result of kaolinite due to the changing in pH in the Zubair reservoir (Lower Cretaceous) during the secondary production by water injection method. Four wells and six core samples within the North Rumaila field are studied, Minerals have been diagnosed by XRD and this specific site of clay minerals was diagnosed within the core samples by scanning electron microscopy (SEM). The core samples are also studied petrogrphically using the polarizing microscope and found that they mainly consist of quartz, while the predominant clay is kaolinite. The effect of pH on the values of permeability was examined through a series of laboratory experiments, as it has been tested in the cases of gradual sudden increase form acidic to alkaline. Petrophysical properties (porosity and initial permeability) were measured a prior to testing. After performing these tests, the final permeability was also measured as well as the rate of formation damage. The final permeability decreased gradually at a rate of 20-30% M Darcy during the injection out with solution of pH 3 to 11 with getting formation damage up to 25%. While in the case injection with sudden increase pH from acid to alkaline directly, there has been a rapid and substantial reduction in the final permeability as average of 28% -72%, with a formation damaged rate of 44%. The results confirmed that the reason of the decrease in the permeability is due to the kaolinite mineral which is subject to the dispersion phenomenon during the change in pH, and the acidic environment is suitable for the reservoir, and does not lead to a reduction in permeability.
Ecosystems provide humans with services that include benefits from food, fresh water, climate regulation, and socio-economic assets. The Mesopotamian marshlands are among the largest wetlands in the Middle East and they provide various benefits. However, ecosystem services of the Marshlands are consistently undervalued in national economic analysis and decision making. This study focusses on the Central Marshes, the first National Park in Iraq, and is the first attempt at valuing a series of ecosystem services from a valuable natural ecosystem in Iraq. We adopted the Toolkit for Ecosystem Services Site-Based Assessment (TESSA) for the determination of biophysical and economic values of services at the site level. Data on key ecosystem se
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Iraq enjoys many factors and ingredients that made it “affect and be affected at the same time” by the American-Iranian conflict from the “strategic geographical position” adjacent to Iran as an important point and that Iraq has been part of this conflict since the last period which witnessed the outbreak of the first Gulf War (1980-1988) because of border problems and a dispute over Shatt al-Arab, and what followed after that, specifically from 2003 when the United States of America and its allies occupied Iraq’s lands and made a political change by the destruction of its security and military institutions. It increased the importance of Iraq in being a subject of competition between the competing parties in exploiting the
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The settlement rate and pore water pressure dissipation rate are mainly controlled by the permeability of soil. Both laboratory and field tests show that the permeability is varied during the loading and consolidation process. It is known that consolidation process is accompanied by decrease in void ratio which leads to decrease in the coefficient of permeability. The importance of the decrease of the coefficient of permeability on the time rate of settlement and pore water pressure needs to be investigated.
This paper takes into account the change in coefficient of permeability during consolidation and studies its effect on consolidation characteristics of a clay layer. The finite element method is used in the analysis and the packag
An interpretative study of the two-dimensional seismic data of the Afaq area was conducted using the Petrel 2017 software. 2D seismic reflection sections are used to give a structural interpretation of Afaq structure based on synthetic seismogram and well log data. Three reflectors, Zubair, Yamama, and Gotina Formations, were selected. These reflectors are defined from well west kifl (wk-1), Where located adjacent to the study area. Structural maps of the Zubair, Yamama, and Gotnia formations are prepared and interpreted, including TWT maps, Average velocity maps, and depth maps. The studies concluded that the Afaq structure area does not contain main faults, but secondary faults with short and limited extensions
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Permeability is one of the essential petrophysical properties of rocks, reflecting the rock's ability to pass fluids. It is considered the basis for building any model to predict well deliverability. Yamama formation carbonate rocks are distinguished by sedimentary cycles that separate formation into reservoir units and insulating layers, a very complex porous system caused by secondary porosity due to substitute and dissolution processes. Those factors create permeability variables and vary significantly. Three ways used for permeability calculation, the firstly was the classical method, which only related the permeability to the porosity, resulting in a weak relationship. Secondly, the flow zone indicator (FZI) was divided reservoir into
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Permeability is an essential parameter in reservoir characterization because it is determined hydrocarbon flow patterns and volume, for this reason, the need for accurate and inexpensive methods for predicting permeability is important. Predictive models of permeability become more attractive as a result.
A Mishrif reservoir in Iraq's southeast has been chosen, and the study is based on data from four wells that penetrate the Mishrif formation. This study discusses some methods for predicting permeability. The conventional method of developing a link between permeability and porosity is one of the strategies. The second technique uses flow units and a flow zone indicator (FZI) to predict the permeability of a rock mass u
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Reservoir fluids properties are very important in reservoir engineering computations such as material balance calculations, well testing analyses, reserve estimates, and numerical reservoir simulations. Isothermal oil compressibility is required in fluid flow problems, extension of fluid properties from values at the bubble point pressure to higher pressures of interest and in material balance calculations (Ramey, Spivey, and McCain). Isothermal oil compressibility is a measure of the fractional change in volume as pressure is changed at constant temperature (McCain). The most accurate method for determining the Isothermal oil compressibility is a laboratory PVT analysis; however, the evaluation of exploratory wells often require an esti
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The depth conversion process is a significant task in seismic interpretation to establish the link between the seismic data in the time domain and the drilled wells in the depth domain. To promote the exploration and development of the Subba oilfield, more accurate depth conversion is required. In this paper, three approaches of depth conversions: Models 1, 2, and 3 are applied from the simplest to the most complex on Nahr Umr Reservoir in Suba oilfield. This is to obtain the best approach, giving less mistakes with the actual depth at well locations and good inter/extrapolation between or away from well controls. The results of these approaches, together with the uncertainty analysis provide a reliable velocity model
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The Central Marshes are one of southern Iraq's most important wetlands and ecosystems. A study on evaluating soil quality and water quality in terms of chemical properties at certain sites in the southern Iraqi Central Marshes has been conducted to investigate their types and suitability for enhancing the agricultural reality of most field crops. Soil and water samples were collected from 15 sites and transferred to the laboratory. In the lab, the following parameters were determined: electrical conductivity (EC), total dissolved salts (TDS), organic materials (OM), pH, gypsum, and total sulfate content (SO3). The tests conducted on the samples indicated that it could be said that the soil of the Central Marshes
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