Advances in Oil and Gas Wellbore Integrity

Journal Name	Impact Factor	CiteScore	Launched Year	First Decision (median)	APC
Energies energies	3.2	5.5	2008	16.1 Days	CHF 2600	Submit
Geosciences geosciences	2.7	5.2	2011	23.6 Days	CHF 1800	Submit
Geotechnics geotechnics	-	-	2021	15.6 Days	CHF 1000	Submit
Minerals minerals	2.5	3.9	2011	18.7 Days	CHF 2400	Submit
Applied Sciences applsci	2.7	4.5	2011	16.9 Days	CHF 2400	Submit

17 pages, 7418 KiB

Open AccessArticle

The Mechanism Study of Fracture Porosity in High-Water-Cut Reservoirs

by Ning Zhang, Daiyin Yin, Guangsheng Cao and Tong Li

Energies 2024, 17(8), 1886; https://doi.org/10.3390/en17081886 - 16 Apr 2024

Viewed by 295

Many onshore oil fields currently adopt water flooding as a means to supplement reservoir energy. However, due to reservoir heterogeneity, significant differences in permeability exist not only between different reservoirs but also within the same reservoir across different planar orientations. After prolonged fluid [...] Read more.

Many onshore oil fields currently adopt water flooding as a means to supplement reservoir energy. However, due to reservoir heterogeneity, significant differences in permeability exist not only between different reservoirs but also within the same reservoir across different planar orientations. After prolonged fluid flushing in the near-wellbore zone of injection wells, the resulting increased flow resistance between layers exacerbates inefficient and ineffective circulation. A considerable amount of remaining oil is left unexploited in untouched areas, significantly impacting the overall recovery. To investigate the multiscale plugging mechanisms of fracture-dominated pore channels in high-water-cut oil reservoirs and achieve efficient management of fractured large channels, this study explores the formation of the fracture-flushing zone-low saturation oil zone. A physical experimental model with fractures and high-intensity flushing is established to analyze changes in pore structure, mineral composition, residual oil distribution, and other characteristics at different positions near the fractures. The research aims to clarify the mechanism behind the formation of large channels with fracture structures. The results indicate that under high-intensity water flushing, cementing materials are washed away by the flowing water, clay particles are carried to the surface with the injected fluid, and permeability significantly increases, forming high-permeability zones with fracture structures. In the rock interior away from the fracture end, channels, corners, and clustered oil content noticeably decrease, while the content of film-like oil substantially increases, and clay minerals are not significantly washed away. Under strong flushing conditions, the number of residual clay particles near the fracture end is mainly influenced by flow velocity and flushing time; thus, the greater the flushing intensity, the faster the water flow, and the longer the flushing time, the fewer residual clay particles near the fracture end. Full article

(This article belongs to the Topic Advances in Oil and Gas Wellbore Integrity)

► Show Figures

Figure 1

36 pages, 16817 KiB

Open AccessReview

Anisotropic Mechanical Behaviors of Shale Rock and Their Relation to Hydraulic Fracturing in a Shale Reservoir: A Review

by Peng-Fei Yin, Sheng-Qi Yang and Pathegama Gamage Ranjith

Energies 2024, 17(7), 1761; https://doi.org/10.3390/en17071761 - 07 Apr 2024

Viewed by 325

Abstract

Shale gas is an important supplement to the supply of natural gas resources and plays an important role on the world’s energy stage. The efficient implementation of hydraulic fracturing is the key issue in the exploration and exploitation of shale gas. The existence [...] Read more.

Shale gas is an important supplement to the supply of natural gas resources and plays an important role on the world’s energy stage. The efficient implementation of hydraulic fracturing is the key issue in the exploration and exploitation of shale gas. The existence of bedding structure results in a distinct anisotropy of shale rock formation. The anisotropic behaviors of shale rock have important impacts on wellbore stability, hydraulic fracture propagation, and the formation of complex fracture networks. This paper briefly reviews previous work on the anisotropic mechanical properties of shale rock and their relation to hydraulic fracturing in shale reservoirs. In this paper, the research status of work addressing the lithological characteristics of shale rock is summarized first, particularly work considering the mineral constituent, which determines its physical and mechanical behavior in essence. Then the anisotropic physical and mechanical properties of shale specimens, including ultrasonic anisotropy, mechanical behavior under uniaxial and triaxial compression tests, and tensile property under the Brazilian test, are summarized, and the state of the literature on fracture toughness anisotropy is discussed. The concerns of anisotropic mechanical behavior under laboratory tests are emphasized in this paper, particularly the evaluation of shale brittleness based on mechanical characteristics, which is discussed in detail. Finally, further concerns such as the effects of bedding plane on hydraulic fracturing failure strength, crack propagation, and failure pattern are also drawn out. This review study will provide a better understanding of current research findings on the anisotropic mechanical properties of shale rock, which can provide insight into the shale anisotropy related to the fracture propagation of hydraulic fracturing in shale reservoirs. Full article

(This article belongs to the Topic Advances in Oil and Gas Wellbore Integrity)

► Show Figures

Figure 1

16 pages, 5190 KiB

Open AccessArticle

Study on the Mechanical and Permeability Characteristics of Gypsum Rock under the Condition of Crude Oil Immersion

by Tingting Jiang, Xiurui Shang, Dongzhou Xie, Dairong Yan, Mei Li and Chunyang Zhang

Energies 2024, 17(7), 1712; https://doi.org/10.3390/en17071712 - 03 Apr 2024

Viewed by 340

Abstract

The utilization of gypsum mine goaf (GMG) for strategic oil reserves can realize the coordinated development of mining and oil storage. However, the variation in mechanical and permeability characteristics of gypsum rock under the action of crude oil erosion is not clear. At [...] Read more.

The utilization of gypsum mine goaf (GMG) for strategic oil reserves can realize the coordinated development of mining and oil storage. However, the variation in mechanical and permeability characteristics of gypsum rock under the action of crude oil erosion is not clear. At the same time, the deformation of gypsum rock caused by crude oil erosion will pose a threat to wellbore integrity. In this paper, a series of tests were carried out on gypsum rock before and after crude oil immersion to explore the effect of crude oil erosion on the mechanical and permeability characteristics of gypsum rock. The results show that crude oil soaking enhances the plastic deformation ability of gypsum rock. After soaking, the cohesion of gypsum rock increases by 14%, but the internal friction angle decreases by 7.2%. During the soaking process, crude oil invades the pores of gypsum rock, which can reduce the value of gypsum rock by 10⁻²⁰ m². Crude oil immersion enhances the deformation resistance of gypsum rock surrounding rock and significantly reduces the permeability, which is conducive to the stability and sealing of gypsum rock goaf during oil storage. The research results are helpful in deepening the understanding of using GMG technology to construct crude oil storage and provide inspiration for the study of the influence of gypsum rock deformation on wellbore integrity under crude oil erosion. Full article

(This article belongs to the Topic Advances in Oil and Gas Wellbore Integrity)

► Show Figures

Figure 1

15 pages, 4162 KiB

Open AccessArticle

Load Calculation and Strength Analysis of the Deepwater Landing Drill Pipe-Lowering Operation

by Guolei He, Linqing Wang, Jiarui Wang, Kaixiang Shen, Hengfu Xiang, Jintang Wang, Haowen Chen, Benchong Xu, Rulei Qin and Guole Yin

Energies 2024, 17(5), 1258; https://doi.org/10.3390/en17051258 - 06 Mar 2024

Viewed by 471

Abstract

A landing string is directly exposed to seawater and subjected to significant stresses and complex deformations due to environmental loads such as wind, waves, and ocean currents during the phase in which the drill string carries the casing to the wellhead. Meanwhile, as [...] Read more.

A landing string is directly exposed to seawater and subjected to significant stresses and complex deformations due to environmental loads such as wind, waves, and ocean currents during the phase in which the drill string carries the casing to the wellhead. Meanwhile, as the water depth increases, the weight of the drill string increases, leading to an increase in the tensile loads borne by the drill string, which can easily cause a risk of failure. Therefore, a quasi-static load calculation model for the deepwater insertion of the pipe column was established. Using the Ansys platform, simulations were conducted for average wind, wave, and ocean current conditions during different months throughout the year. The ultimate loads and stress distributions of the string were derived from theoretical analyses and numerical simulations for different operational sea states, and the suggested safe operating window and desired BOP trolley restraining reaction force for landing strings’ lowering are given according to the existing industry standards. The research findings can help in identifying the potential risks and failure modes of the deepwater landing string under different working conditions. Full article

(This article belongs to the Topic Advances in Oil and Gas Wellbore Integrity)

► Show Figures

Figure 1

12 pages, 5285 KiB

Open AccessArticle

The Insignificant Improvement of Corrosion and Corrosion Fatigue Behavior in Geothermal Environment Applying Boehmit Coatings on High Alloyed Steels

by Anja Pfennig, Wencke Mohring and Marcus Wolf

Appl. Sci. 2024, 14(4), 1575; https://doi.org/10.3390/app14041575 - 16 Feb 2024

Viewed by 424

Abstract

The efficacy of alumina-sol based coatings in a water-free atmosphere at high temperatures suggests a potential solution for enhancing the corrosion resistance of high-alloyed steels in Carbon Capture and Storage (CCS) environments. In this study, coupons of X20Cr13, designed for use as injection [...] Read more.

The efficacy of alumina-sol based coatings in a water-free atmosphere at high temperatures suggests a potential solution for enhancing the corrosion resistance of high-alloyed steels in Carbon Capture and Storage (CCS) environments. In this study, coupons of X20Cr13, designed for use as injection pipes with 13% Chromium and 0.20% Carbon (1.4021, AISI 420), were sol-gel coated with water and ethanol-based alumina. These coated coupons were then exposed to CO₂-saturated saline aquifer water, simulating conditions in the Northern German Basin, for 1000 h at ambient pressure and 60 °C. Corrosion fatigue experiments were also conducted using specimens of X5CrNiMoCuNb16-4 (1.4542, AISI 630), a suitable candidate for geothermal applications, to assess the impact of the ethanol-based coating on the number of cycles to failure at different stress amplitudes. Unfortunately, the coating exhibited early spallation, resulting in corrosion kinetics and corrosion fatigue data identical to those of uncoated specimens. Consequently, the initially promising Boehmit coating is deemed unsuitable for CCS applications and further research therefore not advisable. Full article

(This article belongs to the Topic Advances in Oil and Gas Wellbore Integrity)

► Show Figures

Figure 1

17 pages, 3238 KiB

Open AccessArticle

Study on the Mechanism of Gas Intrusion and Its Transportation in a Wellbore under Shut-in Conditions

by Haifeng Zhu, Ming Xiang, Zhiqiang Lin, Jicheng Yang, Xuerui Wang, Xueqi Liu and Zhiyuan Wang

Energies 2024, 17(1), 242; https://doi.org/10.3390/en17010242 - 03 Jan 2024

Viewed by 563

Abstract

This paper presents a comprehensive study based on multiphase-seepage and wellbore multiphase-flow theories. It establishes a model for calculating the rate of gas intrusion that considers various factors, including formation pore permeability, bottomhole pressure difference, rheology of the drilling fluid, and surface tension. [...] Read more.

This paper presents a comprehensive study based on multiphase-seepage and wellbore multiphase-flow theories. It establishes a model for calculating the rate of gas intrusion that considers various factors, including formation pore permeability, bottomhole pressure difference, rheology of the drilling fluid, and surface tension. Experiments were conducted to investigate the mechanism of gas intrusion under shut-in conditions, and the experimental results were employed to validate the reliability of the proposed method for calculating the gas intrusion rate. Furthermore, this research explores the transportation rates of single bubbles and bubble clusters in drilling fluid under shut-in conditions. Additionally, empirical expressions were derived for the drag coefficient for single bubbles and bubble clusters in the wellbore. These expressions can be used to calculate gas transportation rates for various equivalent radii of single bubbles and bubble clusters. The initial bubble size of intrusive gas, the transportation speed of intrusive gas in the wellbore, the rate of gas intrusion, and variations in the wellbore pressure after gas intrusion were analyzed. Additionally, a method was developed to calculate the rising velocity of bubble clusters in water based on experimental results. The study reveals that the average bubble size in the bubble cluster is significantly smaller than the size of single bubbles generated from the orifice. When the viscosity of the drilling fluid is low, the transportation velocity of the bubble cluster exhibits a positive correlation with the average bubble diameter. When the average bubble diameter exceeds 1 mm, the bubble velocity no longer varies with changes in the bubble-cluster diameter. The research results provide theoretical support for wellbore pressure prediction and pressure control under shutdown conditions. Full article

(This article belongs to the Topic Advances in Oil and Gas Wellbore Integrity)

► Show Figures

Figure 1

12 pages, 4276 KiB

Open AccessArticle

The Sealing Performance of Cement Sheaths under Thermal Cycles for Low-Enthalpy Geothermal Wells

by Anisa Noor Corina and Al Moghadam

Energies 2024, 17(1), 239; https://doi.org/10.3390/en17010239 - 02 Jan 2024

Viewed by 621

Abstract

The repetitive process of shut-in and production in geothermal wells promotes thermal stress on the wellbore components, including annular cement. A cement sheath at a relatively shallow depth undergoes the most significant stress change due to the high differential temperature between the geothermal [...] Read more.

The repetitive process of shut-in and production in geothermal wells promotes thermal stress on the wellbore components, including annular cement. A cement sheath at a relatively shallow depth undergoes the most significant stress change due to the high differential temperature between the geothermal gradient and the production fluid’s temperature. Understanding the impact of cyclical thermal stresses on cement is critical for assessing the barrier integrity at a shallow depth that serves as aquifer protection. A novel large-scale setup simulating a 1.5 m-long casing-cement-casing well section was built to study the changes in cement’s sealing performance of low-enthalpy geothermal wells during production. Using this setup, a cement sheath can be cured similarly to the in situ conditions, and the annular temperature can be cycled under realistic operating conditions. The change in flow rate through the cement sheath before and after cycling is quantified through leak tests. UV dye is injected at the end of the experiment to identify the location and type of damage in the cement sheath. A hydromechanically coupled finite element model was used to estimate the stress evolution in cement during the tests. The model incorporated the impact of cement hydration and strength development during curing. The numerical results were used as a guide to ensure the test design closely mimicked in situ conditions. The results show the presence of a small microannulus immediately after curing due to hydration shrinkage. Thermal cycles reduced the permeability of the microannulus. The size of the micro-annulus was observed to be sensitive to the backpressure applied to the cement sheath, indicating the need for pressure to maintain an open microannulus. Thirty-nine thermal cycles between 80 and 20 °C did not change the permeability of the cement sheath significantly. Tensile cracks in the cement sheath were not continuous and may not be a significant pathway. The new setup allows for measuring cement’s effectiveness in withstanding in situ stress conditions when exposed to thermal cycles such as geothermal and CCS wells. Full article

(This article belongs to the Topic Advances in Oil and Gas Wellbore Integrity)

► Show Figures

Figure 1

14 pages, 7942 KiB

Open AccessArticle

Adsorption/Desorption Performances of Simulated Radioactive Nuclide Cs⁺ on the Zeolite-Rich Geopolymer from the Hydrothermal Synthesis of Fly Ash

by Zhao Zheng, Jun Yang, Maoxuan Cui, Kui Yang, Hui Shang, Xue Ma and Yuxiang Li

Energies 2023, 16(23), 7815; https://doi.org/10.3390/en16237815 - 28 Nov 2023

Cited by 1 | Viewed by 668

Abstract

The operation of nuclear power plants generates a large amount of low- and intermediate-level radioactive waste liquid. Zeolite-rich geopolymers, which are synthesized under hydrothermal conditions from industrial waste fly ash, can effectively immobilize radioactive nuclides. In this study, the synthesis law of zeolite-rich [...] Read more.

The operation of nuclear power plants generates a large amount of low- and intermediate-level radioactive waste liquid. Zeolite-rich geopolymers, which are synthesized under hydrothermal conditions from industrial waste fly ash, can effectively immobilize radioactive nuclides. In this study, the synthesis law of zeolite-rich geopolymers and the adsorption/desorption performances of radioactive nuclide Cs⁺ were researched using XRD, SEM and ICP. The results show that the increase in curing temperatures and NaOH concentrations leads to the transformation of Y-type zeolite to chabazite and cancrinite at low NaNO₃ concentrations. However, at high NaNO₃ concentrations, NaOH above 2 M has no obvious effect on the phase transformation of the main zeolite of chabazite and cancrinite. In the adsorption and desorption experiment of Cs⁺ on the chabazite/garronite-rich geopolymer, it was found that the adsorption of Cs⁺ in the low initial concentration range is more suitable for the Freundlich equation, while the Langmuir equation fits in the adsorption process at the high initial concentration range. Moreover, the desorption kinetics of Cs⁺ are in good agreement with the pseudo-second-order rate equation. Thus, the adsorption of Cs⁺ on chabazite/garronite-rich geopolymers is controlled by both physical and chemical reactions, while desorption is a chemical process. Full article

(This article belongs to the Topic Advances in Oil and Gas Wellbore Integrity)

► Show Figures

Figure 1

11 pages, 2928 KiB

Open AccessArticle

Deepwater PDC Jetting Bit-Drilling Technology Based on Well Structure Slimming

by Weiguo Zhang, Deli Gao, Yijin Zeng and De Yan

Energies 2023, 16(21), 7394; https://doi.org/10.3390/en16217394 - 01 Nov 2023

Viewed by 625

Abstract

Growing global energy demand and limited reserves of traditional energy resources are causing a growing energy shortage. In order to meet future energy needs, new energy resources must be continuously explored. Deepwater drilling research has emerged as one of the key ways to [...] Read more.

Growing global energy demand and limited reserves of traditional energy resources are causing a growing energy shortage. In order to meet future energy needs, new energy resources must be continuously explored. Deepwater drilling research has emerged as one of the key ways to address this issue, and well structure slimming is an effective way to increase drilling speed and reduce costs. The hole size of the second section of deepwater wells decreases from a conventional 660.4 mm to 444.5 mm and increases from 500–800 m to 800–1200 m, creating problems where the conventional 660.4 mm cone bit cannot be used, the rate of penetration (ROP) of the cone bit is low, and the service life is short. To solve these problems, a 444.5 mm artificial polycrystalline diamond compact (PDC) was designed for the first time for use at home or abroad, and according to the characteristics and operation requirements of the 914.4 mm conductor jetting process, a unique anti-collision gauge protector was designed, an innovative bypass nozzle was configured, and a hydraulic design to prevent bit balling in shallow soft mudstone was formulated. PDC jetting bit-drilling technology based on well structure slimming was successfully applied to eight deepwater wells in the eastern South China Sea, which successfully jetted a 914 mm conductor and greatly improved the ROP of their second-section holes. When the below-mudline depth of the second-section hole increased by 37.01%, the average ROP increased by 227.84%. These technical achievements have successfully realized deep drilling with seawater, increased speed and efficiency, achieved good application results, and accumulated valuable experiences that can be used for reducing the cost and increasing the efficiency of offshore drilling operations. Full article

(This article belongs to the Topic Advances in Oil and Gas Wellbore Integrity)

► Show Figures

Figure 1

20 pages, 12902 KiB

Open AccessArticle

Effect of Nanoparticle and Carbon Nanotube Additives on Thermal Stability of Hydrocarbon-Based Drilling Fluids

by Evgeniya I. Lysakova, Andrey V. Minakov and Angelica D. Skorobogatova

Energies 2023, 16(19), 6875; https://doi.org/10.3390/en16196875 - 29 Sep 2023

Viewed by 705

Abstract

The article presents the results of experimental study on the effect of additives of silicon oxide nanoparticles, as well as single-walled and multi-walled carbon nanotubes on the colloidal stability and thermal degradation process of hydrocarbon-based drilling fluids. Such a comprehensive study of hydrocarbon-based [...] Read more.

The article presents the results of experimental study on the effect of additives of silicon oxide nanoparticles, as well as single-walled and multi-walled carbon nanotubes on the colloidal stability and thermal degradation process of hydrocarbon-based drilling fluids. Such a comprehensive study of hydrocarbon-based drilling fluids was carried out for the first time. The effect of the concentration and size of silicon oxide nanoparticles, as well as the type and concentration of nanotubes on the colloidal stability of drilling fluids during thermal aging tests at different temperatures, was investigated. The nanoparticle size varied from 18 to 70 nm, and the concentration ranged from 0.25 to 2 wt.%. Single-walled and multi-walled nanotubes were studied, whose concentration varied from 0.01 to 0.5 wt.%. The thermal aging temperature varied from 30 to 150 °C. According to the results of the investigation, it was shown that the temperature stability of hydrocarbon-based drilling fluids can be significantly improved by adding the above substances. At the same time, it was shown that the use of single-walled nanotubes for thermal stabilization of drilling fluids was several times more effective than the use of multi-walled nanotubes, and tens of times more effective than the use of spherical silicon oxide nanoparticles. Full article

(This article belongs to the Topic Advances in Oil and Gas Wellbore Integrity)

► Show Figures

Figure 1

16 pages, 10530 KiB

Open AccessArticle

Leakage Monitoring and Quantitative Prediction Model of Injection–Production String in an Underground Gas Storage Salt Cavern

by Tingting Jiang, Dongling Cao, Youqiang Liao, Dongzhou Xie, Tao He and Chaoyang Zhang

Energies 2023, 16(17), 6173; https://doi.org/10.3390/en16176173 - 25 Aug 2023

Viewed by 841

Abstract

The leakage of the injection–production string is one of the important hidden dangers for the safe and efficient operation of underground salt cavern gas storage. Although distributed fiber optic temperature measurement system (DTS) can accurately locate the position of the string leakage port, [...] Read more.

The leakage of the injection–production string is one of the important hidden dangers for the safe and efficient operation of underground salt cavern gas storage. Although distributed fiber optic temperature measurement system (DTS) can accurately locate the position of the string leakage port, how to establish the quantitative relationship between the temperature difference and leakage rate of the leakage port still needs further exploration. This paper proposes a new quantitative prediction model based on a DTS for the leakage monitoring of the injection–production string of salt cavern gas storage. The model takes into account the gas’s physical parameters, unstable temperature conditions, and the Joule–Thomson effect. In order to verify the accuracy of the model, a simulation experiment of string leakage based on a DTS was carried out. The test results show that the relative deviation between the predicted leakage rate and the measured value is less than 5% compared with the calculated value. When the leakage rate drops to 0.16 m³/h and the temperature range is less than 0.5 °C, it is difficult to accurately monitor the DTS. The results of this study help to improve the early warning time of underground salt cavern gas storage string leakage. Full article

(This article belongs to the Topic Advances in Oil and Gas Wellbore Integrity)

► Show Figures

Figure 1

17 pages, 13874 KiB

Open AccessArticle

Research on Cuttings Carrying Principle of New Aluminum Alloy Drill Pipe and Numerical Simulation Analysis

by Pengcheng Wu, Chentao Li, Zhen Zhang, Jingwei Yang, Yanzhe Gao, Xianbing Wang, Xiumei Wan, Chengyu Xia and Qunying Guo

Energies 2023, 16(15), 5618; https://doi.org/10.3390/en16155618 - 26 Jul 2023

Viewed by 649

Abstract

In order to improve the cuttings transport ability and well hole purification effect of horizontal shale gas wells in the Sichuan and Chongqing area, a new type of aluminum alloy drill pipe is put forward, and the floatability is validated by theoretical analysis [...] Read more.

In order to improve the cuttings transport ability and well hole purification effect of horizontal shale gas wells in the Sichuan and Chongqing area, a new type of aluminum alloy drill pipe is put forward, and the floatability is validated by theoretical analysis and actual parameter calculation. According to the cuttings migration mechanism, the cuttings cleaning simulation model of the new aluminum alloy drill pipe and the traditional steel drill pipe was established by Fluent, and the hexahedral mesh is used to divide the model. Thus, the mesh independence and convergence of the two models are verified. Then, the simulation model is verified by comparing the calculation results of the two simulation models with the experimental data of the indoor cuttings migration device. Finally, the rock-cleaning ability of the two drill pipes is analyzed under the conditions of changing the cuttings particle size, well inclination angle, displacement, and mechanical speed. Compared with the traditional steel drill pipe, the new aluminum alloy drill pipe can improve the borehole purification capacity by 13% on average. This research result is of great significance in reducing the quality of cuttings in the annulus and improving the borehole purification effect. Full article

(This article belongs to the Topic Advances in Oil and Gas Wellbore Integrity)

► Show Figures

Figure 1

24 pages, 6789 KiB

Open AccessArticle

Shale Cuttings Addition to Wellbore Cement and Their Effect on Unconfined Compressive Strength

by Alexandra Cedola and Runar Nygaard

Energies 2023, 16(12), 4727; https://doi.org/10.3390/en16124727 - 15 Jun 2023

Viewed by 742

Abstract

Mitigation of greenhouse gas emissions is becoming a significant factor in all industries. Cement manufacturing is one of the industries responsible for greenhouse gas emissions, specifically carbon dioxide emissions. Pozzolanic materials have long been used as cement additives due to the pozzolanic reaction [...] Read more.

Mitigation of greenhouse gas emissions is becoming a significant factor in all industries. Cement manufacturing is one of the industries responsible for greenhouse gas emissions, specifically carbon dioxide emissions. Pozzolanic materials have long been used as cement additives due to the pozzolanic reaction that occurs when hydrated and the formation a cementitious material similar to that of cement. In this study, shale, which is a common component found in wellbore drill cuttings, was used in various sizes and quantities to determine the effect it had on the mechanical properties of wellbore cement. The unconfined compressive strength of the cement containing shale was compared to the cement without shale to observe the effect that both the quantity and particle size had on this property. SEM–EDS microscopy was also performed to understand any notable variations in the cement microstructure or composition. The samples containing micron shale appeared to have the best results of all the samples containing shale, and some of the samples had a higher UCS than one or more of the base case samples. Utilization of cuttings as a cement additive is not just beneficial in that it minimizes the need for cuttings removal and recycling, but also in that it reduces the amount of greenhouse gas emissions associated with cement manufacturing. Full article

(This article belongs to the Topic Advances in Oil and Gas Wellbore Integrity)

► Show Figures

Figure 1

25 pages, 32144 KiB

Open AccessArticle

A New Look to the Heletz–Ashdod Oil Field (Southern Israel): A Non-Conventional Hydrocarbon Deposit in the Easternmost Mediterranean

by Lev Eppelbaum and Youri Katz

Geosciences 2023, 13(1), 12; https://doi.org/10.3390/geosciences13010012 - 29 Dec 2022

Viewed by 1944

Abstract

Heletz–Ashdod oil field is the first oil deposit to have been discovered in the Eastern Mediterranean. This deposit has been exploited until the present despite its small reserves. However, this area’s tectonic–geodynamic and structural features must be studied more. Based on the integrated [...] Read more.

Heletz–Ashdod oil field is the first oil deposit to have been discovered in the Eastern Mediterranean. This deposit has been exploited until the present despite its small reserves. However, this area’s tectonic–geodynamic and structural features must be studied more. Based on the integrated regional geological–geophysical analysis, it was proposed that the Heletz terrane, which includes this deposit, is the nodal structure of the Eastern Mediterranean. This terrane is a composite part of the earlier identified Mesozoic terrane belt (MTB). The Heletz terrane’s essential tectonic peculiarity is the MTB’s impact, rotating counterclockwise. Analysis of local geophysical data in this area (gravity, magnetic, and seismic) and regional thermal data examination testifies to the complex mosaic composition of the Heletz structure. It is proved that the crystal basement below the Heletz terrane is characterized by specific properties that do not coincide with the adjacent areas. Finally, a series of structural–paleogeographic and thickness formation maps of the Heletz–Ashdod oil field has been compiled. This investigation shed light on this area’s perspectives and searched other hydrocarbon deposits in the easternmost Mediterranean coastal and shelf zones. Full article

(This article belongs to the Topic Advances in Oil and Gas Wellbore Integrity)

► Show Figures

Figure 1

Topic Menu

Topic Editors

Advances in Oil and Gas Wellbore Integrity

Topic Information

Keywords

Participating Journals

Published Papers (14 papers)

Further Information

Guidelines

MDPI Initiatives

Follow MDPI