Pub Date : 2024-03-31DOI: 10.46717/igj.57.1c.10ms-2024-3-22
Abd Al-Rahim Hashem, A. Al-Zaidy
The tectonic development of the Mesopotamia basin in southern Iraq was studied by calculating subsidence and sedimentation rates for eleven wells distributed over the study area. This was done by calculating backstripping for the Upper Campanian-Maastrichtian sequence. The subsidence rates increased in the south of the region near the Su-4, Su-1, and Lu-2 wells in the Hartha Formation, while the basin of the Shiranish Formation appeared to increase towards the northwest near the Ns-2 well. Then, the subsidence rates in the next formation, Tayarat, increase towards the south, near the wells. Su-1, Su-4, Lu-2. The Hartha Basin was divided into two tectonic parts based on the above. The Shiranish Basin was affected by uplift from the northeast and southeast directions, and due to this, an extremely shallow basin formed with its northern portion exposed during the transgression. At the end of this period, it became the regression stage, where the tectonic uplift began to decrease towards the southwest, and this indicates that the tectonic movement's reactivation due to continental collision, which is evident in the next stage with the deposition of the Alaiji Formation. According to these stratigraphic features, the studied area was divided into two tectonic basins, the northeast basin (Samawa-Nasiriya Subzone) and the southwest basin (Zubair Subzone) separated by tectonic lineament extending from Nasiriya-West Qurna and Zubair oil fields.
{"title":"Basin Analysis and Tectonic Evolution of the Upper Campanian- Maastrichtian Succession, Southern Iraq","authors":"Abd Al-Rahim Hashem, A. Al-Zaidy","doi":"10.46717/igj.57.1c.10ms-2024-3-22","DOIUrl":"https://doi.org/10.46717/igj.57.1c.10ms-2024-3-22","url":null,"abstract":"The tectonic development of the Mesopotamia basin in southern Iraq was studied by calculating subsidence and sedimentation rates for eleven wells distributed over the study area. This was done by calculating backstripping for the Upper Campanian-Maastrichtian sequence. The subsidence rates increased in the south of the region near the Su-4, Su-1, and Lu-2 wells in the Hartha Formation, while the basin of the Shiranish Formation appeared to increase towards the northwest near the Ns-2 well. Then, the subsidence rates in the next formation, Tayarat, increase towards the south, near the wells. Su-1, Su-4, Lu-2. The Hartha Basin was divided into two tectonic parts based on the above. The Shiranish Basin was affected by uplift from the northeast and southeast directions, and due to this, an extremely shallow basin formed with its northern portion exposed during the transgression. At the end of this period, it became the regression stage, where the tectonic uplift began to decrease towards the southwest, and this indicates that the tectonic movement's reactivation due to continental collision, which is evident in the next stage with the deposition of the Alaiji Formation. According to these stratigraphic features, the studied area was divided into two tectonic basins, the northeast basin (Samawa-Nasiriya Subzone) and the southwest basin (Zubair Subzone) separated by tectonic lineament extending from Nasiriya-West Qurna and Zubair oil fields.","PeriodicalId":14847,"journal":{"name":"Iraqi Geological Journal","volume":"18 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140359306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-31DOI: 10.46717/igj.57.1c.11ms-2024-3-23
Obaida Alzekri, Ali Al-Ali, Basim Soltan
The Rumaila oilfield in southern Iraq in Basrah Governorate is considered one of the largest oilfields. Production has been ongoing in the oilfield since the last quarter of the 20th century. The main goal of this research is to determine the spatial distribution and magnitude of deformation inside the Rumaila oilfield. The study aims to investigate the potential correlation between these deformations and their underlying causes, particularly examining the influence of tectonic and nontectonic variables. Microwave satellites are used to validate the existence of deformations resulting from oil production activities or other reasons. In some oilfield areas, there may be subsurface deformations like subsidence or uplift due to tectonic or nontectonic factors like human activity, salt tectonics, basement rock faults, and activities resulting from the collision of the Arabian and Eurasian plates. We used the Sentinel-1A satellite data from June 2017 to December 2022 for the ascending and descending tracks, with 75 and 74 images, respectively. The process yielded excellent results, diagnosing three deformation areas for the three culminations: the first area is located north of the oilfield within the West Qurna area, with deformation ranging from -23 to 6.2 mm/year. The second area represents the North Rumaila oilfield; it had a deformation rate of -33 to 11 mm/year. The last area is the South Rumaila oilfield, where the rate of deformation is about -5.7 to 4.5 mm/year. The Rumaila oilfield experiences subsidence, maybe due to human activity, while uplifts are likely reactions to tectonic factors, as per the study's findings.
{"title":"Neotectonics for the Rumaila Oilfield, Southern Iraq, Using InSAR Techniques","authors":"Obaida Alzekri, Ali Al-Ali, Basim Soltan","doi":"10.46717/igj.57.1c.11ms-2024-3-23","DOIUrl":"https://doi.org/10.46717/igj.57.1c.11ms-2024-3-23","url":null,"abstract":"The Rumaila oilfield in southern Iraq in Basrah Governorate is considered one of the largest oilfields. Production has been ongoing in the oilfield since the last quarter of the 20th century. The main goal of this research is to determine the spatial distribution and magnitude of deformation inside the Rumaila oilfield. The study aims to investigate the potential correlation between these deformations and their underlying causes, particularly examining the influence of tectonic and nontectonic variables. Microwave satellites are used to validate the existence of deformations resulting from oil production activities or other reasons. In some oilfield areas, there may be subsurface deformations like subsidence or uplift due to tectonic or nontectonic factors like human activity, salt tectonics, basement rock faults, and activities resulting from the collision of the Arabian and Eurasian plates. We used the Sentinel-1A satellite data from June 2017 to December 2022 for the ascending and descending tracks, with 75 and 74 images, respectively. The process yielded excellent results, diagnosing three deformation areas for the three culminations: the first area is located north of the oilfield within the West Qurna area, with deformation ranging from -23 to 6.2 mm/year. The second area represents the North Rumaila oilfield; it had a deformation rate of -33 to 11 mm/year. The last area is the South Rumaila oilfield, where the rate of deformation is about -5.7 to 4.5 mm/year. The Rumaila oilfield experiences subsidence, maybe due to human activity, while uplifts are likely reactions to tectonic factors, as per the study's findings.","PeriodicalId":14847,"journal":{"name":"Iraqi Geological Journal","volume":"12 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140359738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-31DOI: 10.46717/igj.57.1c.1ms-2024-3-13
V. Mehdipour, A. Kadkhodaie, Salih Awadh
Integrated reservoir rock typing in carbonate reservoirs is a significant step in reservoir modelling. The key purpose of this study is the identification of integrated rock types in the Sarvak Formation of an Iranian oilfield. In this study, electrofacies (EFAC) analysis of the Sarvak reservoir was done in detail to determine the reservoir quality and rock types of the Sarvak Formation in the studied field. The core data and conventional petrophysical logs were used for rock typing. Some petrophysical logs such as porosity, sonic, neutron, density, and Photo electric factor were applied as input data for electrofacies analysis. Multi-Resolution Graph-Based Clustering was used among six approaches, resulting in four electrofacies after merging similar clusters. EFAC-1 has the lowest porosity, and EFAC-4 has the highest porosity. In addition, based on Winland and Amaefule approaches, three rock types were determined using core data (porosity and permeability). As a result, three rock types were defined; rock type-1 has the smallest pore-throat size and flow zone indicator while rock type-3 has the highest ones. The correlation coefficient between permeability and porosity in each rock type is more than 80%. Rock type 1 is mainly composed of EFAC-1 and EFAC-2, while rock types 2 and 3 share mostly the EFACs 1, 3 and 4.
{"title":"Determination of Reservoir Rock Type in Sarvak Reservoir of an Iranian Oilfield","authors":"V. Mehdipour, A. Kadkhodaie, Salih Awadh","doi":"10.46717/igj.57.1c.1ms-2024-3-13","DOIUrl":"https://doi.org/10.46717/igj.57.1c.1ms-2024-3-13","url":null,"abstract":"Integrated reservoir rock typing in carbonate reservoirs is a significant step in reservoir modelling. The key purpose of this study is the identification of integrated rock types in the Sarvak Formation of an Iranian oilfield. In this study, electrofacies (EFAC) analysis of the Sarvak reservoir was done in detail to determine the reservoir quality and rock types of the Sarvak Formation in the studied field. The core data and conventional petrophysical logs were used for rock typing. Some petrophysical logs such as porosity, sonic, neutron, density, and Photo electric factor were applied as input data for electrofacies analysis. Multi-Resolution Graph-Based Clustering was used among six approaches, resulting in four electrofacies after merging similar clusters. EFAC-1 has the lowest porosity, and EFAC-4 has the highest porosity. In addition, based on Winland and Amaefule approaches, three rock types were determined using core data (porosity and permeability). As a result, three rock types were defined; rock type-1 has the smallest pore-throat size and flow zone indicator while rock type-3 has the highest ones. The correlation coefficient between permeability and porosity in each rock type is more than 80%. Rock type 1 is mainly composed of EFAC-1 and EFAC-2, while rock types 2 and 3 share mostly the EFACs 1, 3 and 4.","PeriodicalId":14847,"journal":{"name":"Iraqi Geological Journal","volume":"40 48","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140357796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-31DOI: 10.46717/igj.57.1c.3ms-2024-3-15
Manar Amer, Dahlia A. Al-Obaidi
Empirical and statistical methodologies have been established to acquire accurate permeability identification and reservoir characterization, based on the rock type and reservoir performance. The identification of rock facies is usually done by either using core analysis to visually interpret lithofacies or indirectly based on well-log data. The use of well-log data for traditional facies prediction is characterized by uncertainties and can be time-consuming, particularly when working with large datasets. Thus, Machine Learning can be used to predict patterns more efficiently when applied to large data. Taking into account the electrofacies distribution, this work was conducted to predict permeability for the four wells, FH1, FH2, FH3, and FH19 from the Yamama reservoir in the Faihaa Oil Field, southern Iraq. The framework includes: calculating permeability for uncored wells using the classical method and FZI method. Topological mapping of input space into clusters is achieved using the self-organizing map (SOM), as an unsupervised machine-learning technique. By leveraging data obtained from the four wells, the SOM is effectively employed to forecast the count of electrofacies present within the reservoir. According to the findings, the permeability calculated using the classical method that relies exclusively on porosity is not close enough to the actual values because of the heterogeneity of carbonate reservoirs. Using the FZI method, in contrast, displays more real values and offers the best correlation coefficient. Then, the SOM model and cluster analysis reveal the existence of five distinct groups.
{"title":"Permeability Prediction and Facies Distribution for Yamama Reservoir in Faihaa Oil Field: Role of Machine Learning and Cluster Analysis Approach","authors":"Manar Amer, Dahlia A. Al-Obaidi","doi":"10.46717/igj.57.1c.3ms-2024-3-15","DOIUrl":"https://doi.org/10.46717/igj.57.1c.3ms-2024-3-15","url":null,"abstract":"Empirical and statistical methodologies have been established to acquire accurate permeability identification and reservoir characterization, based on the rock type and reservoir performance. The identification of rock facies is usually done by either using core analysis to visually interpret lithofacies or indirectly based on well-log data. The use of well-log data for traditional facies prediction is characterized by uncertainties and can be time-consuming, particularly when working with large datasets. Thus, Machine Learning can be used to predict patterns more efficiently when applied to large data. Taking into account the electrofacies distribution, this work was conducted to predict permeability for the four wells, FH1, FH2, FH3, and FH19 from the Yamama reservoir in the Faihaa Oil Field, southern Iraq. The framework includes: calculating permeability for uncored wells using the classical method and FZI method. Topological mapping of input space into clusters is achieved using the self-organizing map (SOM), as an unsupervised machine-learning technique. By leveraging data obtained from the four wells, the SOM is effectively employed to forecast the count of electrofacies present within the reservoir. According to the findings, the permeability calculated using the classical method that relies exclusively on porosity is not close enough to the actual values because of the heterogeneity of carbonate reservoirs. Using the FZI method, in contrast, displays more real values and offers the best correlation coefficient. Then, the SOM model and cluster analysis reveal the existence of five distinct groups.","PeriodicalId":14847,"journal":{"name":"Iraqi Geological Journal","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140361391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-31DOI: 10.46717/igj.57.1c.4ms-2024-3-16
D. Sadeq, Ahmed Almomen, Haider Hamad, U. Alameedy
Reliable estimation of critical parameters such as hydrocarbon pore volume, water saturation, and recovery factor are essential for accurate reserve assessment. The inherent uncertainties associated with these parameters encompass a reasonable range of estimated recoverable volumes for single accumulations or projects. Incorporating this uncertainty range allows for a comprehensive understanding of potential outcomes and associated risks. In this study, we focus on the oil field located in the northern part of Iraq and employ a Monte Carlo based petrophysical uncertainty modeling approach. This method systematically considers various sources of error and utilizes effective interpretation techniques. Leveraging the current state of available data, our approach generates a wide range of theoretically possible results. Furthermore, establishing a set of probabilities to indicate the likelihood of each possible outcome is of utmost importance. By implementing this approach, we aim to enhance reserve assessments by accounting for petrophysical uncertainties, thereby providing decision makers with valuable insights into the range of possible outcomes and associated risks. This study contributes to a more robust understanding of recoverable reserves and supports informed decision making in the oil and gas industry.
{"title":"Exploring the Impact of Petrophysical Uncertainties on Recoverable Reserves: A Case Study","authors":"D. Sadeq, Ahmed Almomen, Haider Hamad, U. Alameedy","doi":"10.46717/igj.57.1c.4ms-2024-3-16","DOIUrl":"https://doi.org/10.46717/igj.57.1c.4ms-2024-3-16","url":null,"abstract":"Reliable estimation of critical parameters such as hydrocarbon pore volume, water saturation, and recovery factor are essential for accurate reserve assessment. The inherent uncertainties associated with these parameters encompass a reasonable range of estimated recoverable volumes for single accumulations or projects. Incorporating this uncertainty range allows for a comprehensive understanding of potential outcomes and associated risks. In this study, we focus on the oil field located in the northern part of Iraq and employ a Monte Carlo based petrophysical uncertainty modeling approach. This method systematically considers various sources of error and utilizes effective interpretation techniques. Leveraging the current state of available data, our approach generates a wide range of theoretically possible results. Furthermore, establishing a set of probabilities to indicate the likelihood of each possible outcome is of utmost importance. By implementing this approach, we aim to enhance reserve assessments by accounting for petrophysical uncertainties, thereby providing decision makers with valuable insights into the range of possible outcomes and associated risks. This study contributes to a more robust understanding of recoverable reserves and supports informed decision making in the oil and gas industry.","PeriodicalId":14847,"journal":{"name":"Iraqi Geological Journal","volume":"31 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140359155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-31DOI: 10.46717/igj.57.1c.16ms-2024-3-28
R. Qader, G. Hamasur, A. Surdashy
Rock slope, slope height, rock discontinuity orientations, and undesigned excavated slopes are the primary contributing factors to the instability of the road in the mountain area. The eight rock slopes in Mergasur town, NE-Iraq, were chosen to be assessed for stability using the kinematic approach with DIPS v6.008 software to determine the type of slope failure and the Q-slope system applied to determine the stability condition. This is an efficient approach for classifying rock slope engineering. According to the kinematic results, stations 1–5 and 7 may have planar sliding, whereas stations 4–8 may experience wedge sliding, stations 1, 2, and 7-8 may experience flexural toppling, and station 3 may have direct toppling. In accordance with the Q-slope system results, stability conditions are determined by projecting the Q-slope and slope angle values on the Q-slope chart.
{"title":"Q-Slope System for Assessing the Stability of Rock Slopes in Selected Area, Mergasur Town, Erbil, Kurdistan Region, NE Iraq","authors":"R. Qader, G. Hamasur, A. Surdashy","doi":"10.46717/igj.57.1c.16ms-2024-3-28","DOIUrl":"https://doi.org/10.46717/igj.57.1c.16ms-2024-3-28","url":null,"abstract":"Rock slope, slope height, rock discontinuity orientations, and undesigned excavated slopes are the primary contributing factors to the instability of the road in the mountain area. The eight rock slopes in Mergasur town, NE-Iraq, were chosen to be assessed for stability using the kinematic approach with DIPS v6.008 software to determine the type of slope failure and the Q-slope system applied to determine the stability condition. This is an efficient approach for classifying rock slope engineering. According to the kinematic results, stations 1–5 and 7 may have planar sliding, whereas stations 4–8 may experience wedge sliding, stations 1, 2, and 7-8 may experience flexural toppling, and station 3 may have direct toppling. In accordance with the Q-slope system results, stability conditions are determined by projecting the Q-slope and slope angle values on the Q-slope chart.","PeriodicalId":14847,"journal":{"name":"Iraqi Geological Journal","volume":"18 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140359474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-31DOI: 10.46717/igj.57.1c.9ms-2024-3-21
Wael El Sherbeny, Lobna Sharaf, A. Baghdady, M. Rizk, A. Farag
This case study represents an approach of applying a systematic risk assessment in combination with Post-Drilling Geomechanics modeling to properly understand the root causes of drilling challenges through Late Messenain – Early Tortunian formations, Balsam field, onshore East Nile Delta, Egypt. The aim of the analysis is to support pro-actively the operator to drill the future wells safely through the problematic formation in the field. According to the risk assessment; drilling the reservoir section experienced three major challenges including downhole losses, tight spots, and differential sticking. The case study includes two phases; phase-I (Risk Identification Phase) considers defining the drilling hazards utilizing daily drilling reports (DDR’s), meanwhile Phase-II considers (1D Geomechanics & Wellbore Stability) constructing a post-drill Geomechanics models using a licensed Software using all available E-logs, borehole image and caliper data. Post-drill geomechanics models calibrated using drilling events, borehole image, caliper data and reservoir pressure measurements. The results of both risk identification and geomechanics models confirms that tight spots and differential sticking was related to overbalance drilling with improper wellbore strengthening package of drilling fluids that results in invasion/pressure transmission and eventually thick filter cake across high permeable/depleted sandstone rock. the study results indicates that the drilling challenges might be related to certain geomechanics signs e.g. time-dependent failures, weak bedding planes and pressure transmissions. Those Geomechanics events could be related to fluids-rock interactions and lack of improper wellbore strengthening art. The study outcomes would help in minimizing drilling challenges for future wells considering both drilling practices and drilling fluids design.
{"title":"Understanding the Mechanisms of Drilling Challenges through a Systematic Risk Assessment and Geomechanics Modeling; a Post-Drill Case Study, Balsam Field, Onshore East Nile Delta, Egypt","authors":"Wael El Sherbeny, Lobna Sharaf, A. Baghdady, M. Rizk, A. Farag","doi":"10.46717/igj.57.1c.9ms-2024-3-21","DOIUrl":"https://doi.org/10.46717/igj.57.1c.9ms-2024-3-21","url":null,"abstract":"This case study represents an approach of applying a systematic risk assessment in combination with Post-Drilling Geomechanics modeling to properly understand the root causes of drilling challenges through Late Messenain – Early Tortunian formations, Balsam field, onshore East Nile Delta, Egypt. The aim of the analysis is to support pro-actively the operator to drill the future wells safely through the problematic formation in the field. According to the risk assessment; drilling the reservoir section experienced three major challenges including downhole losses, tight spots, and differential sticking. The case study includes two phases; phase-I (Risk Identification Phase) considers defining the drilling hazards utilizing daily drilling reports (DDR’s), meanwhile Phase-II considers (1D Geomechanics & Wellbore Stability) constructing a post-drill Geomechanics models using a licensed Software using all available E-logs, borehole image and caliper data. Post-drill geomechanics models calibrated using drilling events, borehole image, caliper data and reservoir pressure measurements. The results of both risk identification and geomechanics models confirms that tight spots and differential sticking was related to overbalance drilling with improper wellbore strengthening package of drilling fluids that results in invasion/pressure transmission and eventually thick filter cake across high permeable/depleted sandstone rock. the study results indicates that the drilling challenges might be related to certain geomechanics signs e.g. time-dependent failures, weak bedding planes and pressure transmissions. Those Geomechanics events could be related to fluids-rock interactions and lack of improper wellbore strengthening art. The study outcomes would help in minimizing drilling challenges for future wells considering both drilling practices and drilling fluids design.","PeriodicalId":14847,"journal":{"name":"Iraqi Geological Journal","volume":"39 26","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140357890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-31DOI: 10.46717/igj.57.1c.12ms-2024-3-24
H. Bakri, Imran Imran, U. Irvan, Adi Maulana
The origin of magma, source materials, and geodynamic setting of plutonic and volcanic rocks was elucidated by studying the characteristics of the rocks in the Tanjung area, South Sulawesi, Indonesia. The composition of plutonic rocks is dominated by granodiorite, granite, monzonite, and quartz monzonite, whereas volcanic rocks consist of porphyry basalt, amygdaloidal basalt, trachyte, and trachy-andesite. The main minerals in the rocks are quartz, K-feldspar plagioclase feldspars, Hornblende, biotite, pyroxene, and some opaque minerals. Plots of plutonic rock samples with calc-alkaline affinity indicated a typical I-type granitic rock. Meanwhile, plots of volcanic rock samples with calc-alkaline to shoshonitic affinity indicated S- and I-type basaltic rocks. Harker diagrams suggested that the rocks underwent crystallisation fractionation during magma evolution. Plutonic and Volcanic rocks showed enrichment of LILE and LREE and negative Eu anomalies, which resemble continental crust affinity. It is a product of partial melting in the upper continental crust. The geochemical characteristics demonstrate the relationship between the subduction environment and a continental arc.
通过研究印度尼西亚南苏拉威西丹戎地区的岩石特征，阐明了板岩和火山岩的岩浆起源、源材料和地球动力学环境。板岩的成分主要是花岗闪长岩、花岗岩、单斜长岩和石英单斜长岩，而火山岩则由斑状玄武岩、杏仁状玄武岩、闪长岩和闪长安山岩组成。岩石中的主要矿物是石英、K长石斜长石、角闪石、生物辉石、辉石和一些不透明矿物。具有钙碱性亲和力的深成岩样本图显示出典型的 I 型花岗岩。与此同时，钙碱性与霰石亲和性的火山岩样本图则显示出 S 型和 I 型玄武岩。哈克图显示这些岩石在岩浆演化过程中经历了结晶分馏。深成岩和火山岩显示出 LILE 和 LREE 的富集以及 Eu 的负异常，这与大陆地壳亲和性相似。它是上部大陆地壳部分熔融的产物。地球化学特征证明了俯冲环境与大陆弧之间的关系。
{"title":"Petrology and Geochemistry of Intrusive Rocks in the Tanjung Area, South Sulawesi, Indonesia: Implications for Magma Origin, Source Materials, and Geodynamic Setting","authors":"H. Bakri, Imran Imran, U. Irvan, Adi Maulana","doi":"10.46717/igj.57.1c.12ms-2024-3-24","DOIUrl":"https://doi.org/10.46717/igj.57.1c.12ms-2024-3-24","url":null,"abstract":"The origin of magma, source materials, and geodynamic setting of plutonic and volcanic rocks was elucidated by studying the characteristics of the rocks in the Tanjung area, South Sulawesi, Indonesia. The composition of plutonic rocks is dominated by granodiorite, granite, monzonite, and quartz monzonite, whereas volcanic rocks consist of porphyry basalt, amygdaloidal basalt, trachyte, and trachy-andesite. The main minerals in the rocks are quartz, K-feldspar plagioclase feldspars, Hornblende, biotite, pyroxene, and some opaque minerals. Plots of plutonic rock samples with calc-alkaline affinity indicated a typical I-type granitic rock. Meanwhile, plots of volcanic rock samples with calc-alkaline to shoshonitic affinity indicated S- and I-type basaltic rocks. Harker diagrams suggested that the rocks underwent crystallisation fractionation during magma evolution. Plutonic and Volcanic rocks showed enrichment of LILE and LREE and negative Eu anomalies, which resemble continental crust affinity. It is a product of partial melting in the upper continental crust. The geochemical characteristics demonstrate the relationship between the subduction environment and a continental arc.","PeriodicalId":14847,"journal":{"name":"Iraqi Geological Journal","volume":"78 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140360240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-31DOI: 10.46717/igj.57.1c.8ms-2024-3-20
Fahad M. Al-Najm, Mayssa Shehab, H. Al-Samer, Mohammed Hafiz
The Mishrif Formation was studied in seven wells that were distributed in the Nasiriya Oil-field, southern Iraq, well logs were obtained for these wells and included: Gamma ray, Neutron, Density and Resistivity log. The Nasiriya Oil field is located at the unstable platform Mesopotamian zone. The Mishrif Formation was divided into two rock units, the upper MA and lower MB, separated by insulating shale rocks based on the gamma ray log. Furthemore, the lower rock unit was also divided into two reservoir units MB1 and MB2. The petrophysical properties of the formation were studied using various logs and through realationships between the logs. The petrophysical study of the water and hydrocarbon saturations showed that the formation contains varying proportions and quantities of water and hydrocarbons that can be produced. The research also included a statistical study and calculation of reservoir heterogeneity using two methods: first using the Dykstra-Parsons Coefficient, where the results showed that is, the Lateral extension of the reservoir units of the study wells are heterogeneous, and second using the Lorenz coefficient, where the results showed that wells heterogeneous distribution, while Ns-9 and Ns-16 wells a homogeneous distribution.
{"title":"Studying the Statistical and Petrophysical of the Mishrif Formation in the Nasiriya Oilfield, Southern Iraq","authors":"Fahad M. Al-Najm, Mayssa Shehab, H. Al-Samer, Mohammed Hafiz","doi":"10.46717/igj.57.1c.8ms-2024-3-20","DOIUrl":"https://doi.org/10.46717/igj.57.1c.8ms-2024-3-20","url":null,"abstract":"The Mishrif Formation was studied in seven wells that were distributed in the Nasiriya Oil-field, southern Iraq, well logs were obtained for these wells and included: Gamma ray, Neutron, Density and Resistivity log. The Nasiriya Oil field is located at the unstable platform Mesopotamian zone. The Mishrif Formation was divided into two rock units, the upper MA and lower MB, separated by insulating shale rocks based on the gamma ray log. Furthemore, the lower rock unit was also divided into two reservoir units MB1 and MB2. The petrophysical properties of the formation were studied using various logs and through realationships between the logs. The petrophysical study of the water and hydrocarbon saturations showed that the formation contains varying proportions and quantities of water and hydrocarbons that can be produced. The research also included a statistical study and calculation of reservoir heterogeneity using two methods: first using the Dykstra-Parsons Coefficient, where the results showed that is, the Lateral extension of the reservoir units of the study wells are heterogeneous, and second using the Lorenz coefficient, where the results showed that wells heterogeneous distribution, while Ns-9 and Ns-16 wells a homogeneous distribution.","PeriodicalId":14847,"journal":{"name":"Iraqi Geological Journal","volume":"15 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140361170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-29DOI: 10.46717/igj.57.1b.6ms-2024-2-15
Ahmed Baghdadi, Abdullah El-Sayed, Abdel-Kahlek El-Werr, Ali Farag
Permeability derived from magnetic resonance advanced logging tools was used to unlock the Pliocene sandstone reservoir heterogeneity. Permeability prediction from well logs is a significant target due to the unavailability of core data. The hydraulic flow unit approach is used to classify the reservoir rocks according to their porosity-permeability relationship. The predicted permeability is calculated using Sapphire-Dh magnetic resonance porosity and permeability relationship for each flow unit. Flow Zone Indicator and the quality flow unit have a direct proportion relationship. For the model's verification, the predicted permeability is plotted against the measured resonance permeability in Sapphire-Dh as a reference studied well, showing highly matching results. Accordingly, the applied approach is implemented in the other three wells, which have neither core samples nor advanced logs measurements.
{"title":"Permeability Prediction Using Advanced Magnetic Resonance Tools and Hydraulic Reservoir Units Techniques for the Pliocene Sand Reservoirs, Sapphire Offshore Gas Field, Mediterranean, Egypt","authors":"Ahmed Baghdadi, Abdullah El-Sayed, Abdel-Kahlek El-Werr, Ali Farag","doi":"10.46717/igj.57.1b.6ms-2024-2-15","DOIUrl":"https://doi.org/10.46717/igj.57.1b.6ms-2024-2-15","url":null,"abstract":"Permeability derived from magnetic resonance advanced logging tools was used to unlock the Pliocene sandstone reservoir heterogeneity. Permeability prediction from well logs is a significant target due to the unavailability of core data. The hydraulic flow unit approach is used to classify the reservoir rocks according to their porosity-permeability relationship. The predicted permeability is calculated using Sapphire-Dh magnetic resonance porosity and permeability relationship for each flow unit. Flow Zone Indicator and the quality flow unit have a direct proportion relationship. For the model's verification, the predicted permeability is plotted against the measured resonance permeability in Sapphire-Dh as a reference studied well, showing highly matching results. Accordingly, the applied approach is implemented in the other three wells, which have neither core samples nor advanced logs measurements.","PeriodicalId":14847,"journal":{"name":"Iraqi Geological Journal","volume":"103 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140411174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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