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Collaborating Authors
Curtin University
Effect of Clay Minerals Heterogeneity on Wettability Measurements: Implications for CO2 Storage
Fauziah, Cut Aja (Curtin University) | Al-Khdheeawi, Emad A. (Curtin University) | Iglauer, Stefan (Edith Cowan University) | Barifcani, Ahmed (Curtin University)
Abstract Surfaces heterogeneity is a well-investigated fact and it represents a fundamental characteristic of the rock surfaces. Many factors are responsible for this surfaces heterogeneity such as the existence of impurities, surface roughness, the arrangement of the local crystalline, and the variation in crystal faces. Although the presence of clay minerals heterogeneity has been proven previously, its effect on the wettability measurements and the CO2 storage capacity has not been studied yet. Thus, in this paper, we therefore systematically measured the contact angle (wettability) of pure clay minerals (i.e. montmorillonite, illite and kaolinite) and mixed clay mineral (i.e. 14 wt% kaolinite, 48 wt% illite and 38 wt% montmorillonite) for CO2/brine systems. For both pure and mixed clay minerals, advancing and receding contact angles were measured at various pressures (5 MPa, 10 MPa, 15 MPa and 20 MPa) and temperatures (305 K and 333 K). The results show that clay minerals heterogeneity has a significant effect on the wettability measurements. The contact angles increase with increasing pressure for both pure clays and mixed clay. However, there is a slight increase in contact angles of pure clays as the pressure increases, compared to the mixed clay. For instance, the advancing contact angles have been increased from 77⁰ to 110⁰, 53⁰ to 67⁰, and 41⁰ to 57⁰ for pure montmorillonite, illite and kaolinite, respectively, by increasing the pressure from 5 MPa to 20 MPa. Meanwhile, the contact angle of mixed clay has been increased from 47⁰ to 93⁰ (i.e. the wettability of the mixed clay minerals has been altered from weakly water-wet to intermediate-wet) at the same pressures increase (from 5 MPa to 20 MPa). Furthermore, the results illustrate that the contact angle of both pure and mixed clay slightly reduce with increasing temperature from 305 K and 333 K. Thus, we conclude that clay minerals heterogeneity affects the clay wettability and leads to increase the contact angle at high pressures. Consequently, clay minerals heterogeneity reduce the CO2 storage capacity and containment security at high pressures. This study has important implications for deep geological carbon sequestration, CO2 dynamics and spreading in the geological reservoir.
- Research Report > New Finding (0.49)
- Research Report > Experimental Study (0.35)
- Well Drilling > Drilling Fluids and Materials > Drilling fluid selection and formulation (chemistry, properties) (1.00)
- Reservoir Description and Dynamics > Storage Reservoir Engineering > CO2 capture and sequestration (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
- (4 more...)
Acoustic Data Driven Application of Principal Component Multivariate Regression Analysis in the Development of Unconfined Compressive Strength Prediction Models for Shale Gas Reservoirs
Iferobia, Cajetan Chimezie (Universiti Teknologi PETRONAS) | Ahmad, Maqsood (Universiti Teknologi PETRONAS) | Salim, Ahmed Mohammed (Universiti Teknologi PETRONAS) | Sambo, Chico (University of Lousiana at Lafayette) | Michaels, Ifechukwu Harrison (Curtin University)
Abstract Unconfined compressive strength (UCS) equally represented as geomechanical strength remains a critical mechanical property in the successful implementation of key technologies for shale gas reservoirs’ development and production. Attention has been less concentrated on prediction models’ development for shale geomechanical strength evaluation. Majority of the existing shale geomechanical strength correlations are dependent on single log input parameter, which is insufficient to account for the complex and non-linear behaviour of UCS across the entire reservoir interval of interest. The high relevance of UCS has therefore triggered the need for the application of an integrated system of principal component – multivariate regression analysis in driving UCS predictive models’ development for shale gas reservoirs. Generated acoustic datasets of notable shale gas reservoirs (Marcellus, Montney, Longmaxi and Roseneath) in respective countries (United States of America (USA), Canada, China and Australia) were used. Statistical test analysis was conducted in validation for wider applications of the developed UCS prediction models. Models development were driven by 21,708 datapoints of acoustic parameters, models’ accuracy ratings were above 99%, R-squared values had high degrees of closeness to unity, mean absolute percentage error (MAPE) values were at less than 10% and coefficient of variation (COV) at less than (1.0). UCS prediction models were all dependent on multiple direct log measured acoustic parameters in distinction to existing UCS empirical correlations; thus, a pure reflection of significant boost to the accuracy and reliability of UCS measurements for shale gas reservoirs. The developed prediction models will promote geomechanical strength accountability and lead to creation of a robust base in minimization of wellbore instability problems, optimization of wellbore trajectory and containment of hydraulic fractures. This will significantly contribute in putting gas resources of shale reservoirs with enormous potentials, at the forefront of quantitatively meeting natural gas requirements in global energy demand.
- Asia (1.00)
- North America > Canada > British Columbia (0.68)
- North America > United States > Virginia (0.48)
- (2 more...)
- Research Report > New Finding (0.71)
- Research Report > Experimental Study (0.71)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock > Shale (1.00)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Geophysics > Seismic Surveying (1.00)
- Geophysics > Borehole Geophysics (1.00)
- Oceania > Australia > South Australia > Cooper Basin > Murteree Formation (0.99)
- Oceania > Australia > Queensland > Cooper Basin (0.99)
- North America > United States > West Virginia > Appalachian Basin > Marcellus Shale Formation (0.99)
- (61 more...)
The overestimated elastic moduli from digital rock images: Computational reasons
Liang, Jiabin (Curtin University) | Glubokovskikh, Stanislav (Curtin University) | Gurevich, Boris (Curtin University) | Lebedev, Maxim (Curtin University) | Vialle, Stephanie (Curtin University)
Digital rock physics is a fast-evolving technology, which can help to understand the relationship between pore-scale microstructures and the effective elastic moduli of a rock. Elastic moduli computed from micro-CT images are usually much higher than those derived from laboratory measurements. This discrepancy is often attributed to image resolution, which may often be too coarse to resolve micro pores and grain contacts. While the volume fraction of these pores is small, they may still significantly influence the mechanical properties of a rock. We design a series of numerical tests on two simplified contact geometries and several micro-CT images of a Bentheimer sandstone sample to show that meshing might be the main reason for the systematic errors in the computed elastic moduli. The mesh size must be sufficient to discretize the rapidly changing stress at grain contacts which requires very fine mesh size. This size should often be much smaller than the resolution of the original scans. Presentation Date: Tuesday, October 13, 2020 Session Start Time: 9:20 AM Presentation Time: 9:20 AM Location: Poster Station 7 Presentation Type: Poster
- Geology > Geological Subdiscipline > Geomechanics (0.72)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Sandstone (0.30)
Wettability dependent P-wave scattering and velocity saturation relation in granular medium
Li, Jimmy X. (Curtin University) | Rezaee, Reza (Curtin University) | Müller, Tobias M. (Department of Seismology) | Madadi, Mahyar (University of Melbourne) | Sarmadivaleh, Mohammad (Curtin University)
We investigate elastic wave scattering and the velocitysaturation- relation (VSR) in glass bead packings resembling unconsolidated granular sediments in the shallow subsurface. While it is known that wave scattering in dry granular media is dictated by the presence of force chains, the effect on the VSR in partially saturated granular media under different wettability conditions remains unexplored. To make progress in this direction, we design and conduct laboratory experiments by combining core flooding and ultrasonic measurement in glass bead packings with different wettability. The experimental results show that there is a transition from a stable P-wave pulse propagating in an effective medium at low and moderate saturations to a set of incoherently scattered waves at high saturation. This observation holds true for either the water- or the gaswetting glass bead packings. However, the incoherent scattering in the gas-wetting case is negligibly small. We interpret these observations through alteration of the force chains. Only if water wets the grains, can the liquid enter the grain contacts. Then, its viscoelastic properties contribute to the reinforcement of the force chain and also increases its characteristic length scale. This leads to a P-wave velocity enhancement and to scattering. On the contrast, in the gas wetting case, the wetting phase gas prevents the water from the direct contact with the glass beads therefore stops the extension of the force chains, which inhibits the wave scattering and viscous coupling between the water and the glass beads. Presentation Date: Wednesday, October 14, 2020 Session Start Time: 8:30 AM Presentation Time: 9:20 AM Location: 360A Presentation Type: Oral
- Research Report > New Finding (0.34)
- Research Report > Experimental Study (0.34)
We evaluate the feasibility of predicting seismic velocities based on drilling dynamics. In practice, drilling is often inefficient, resulting in the drilling dynamics losing correspondence with the mechanical energy required to penetrate a rock mass. Based on real data for a 1400 ft interval intersecting carbonate, clastic, and anhydrite formations, we show that downhole accelerometers provide sufficient information to distinguish the effects associated with the “drillstring noise” and rock properties. To this end, we modified the forward stagewise regression to provide a quantitative measure of the importance of various measurements while drilling. The three most critical features were found to be the intensity of axial vibrations (RMS of the accelerations in the 35-170 Hz range), mean specific mechanical energy (related to the drilling efficiency), and the rate of drill-bit penetration. The final regression equation provides much better goodness-of-fit for the challenging geological conditions compared to existing methods. Presentation Date: Tuesday, October 13, 2020 Session Start Time: 1:50 PM Presentation Time: 4:45 PM Location: 351D Presentation Type: Oral
- Geophysics > Borehole Geophysics (1.00)
- Geophysics > Seismic Surveying > Seismic Modeling > Velocity Modeling (0.35)
- Well Drilling > Drilling Operations (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Seismic processing and interpretation (1.00)
- Reservoir Description and Dynamics > Formation Evaluation & Management > Open hole/cased hole log analysis (1.00)
- Data Science & Engineering Analytics > Information Management and Systems > Artificial intelligence (1.00)
ABSTRACT Typical ultrasonic laboratory measurements of rock physical properties are conducted with ultrasonic transducers that are relatively large compared to the rock sample. We have determined the impact of the transducer size on the resulting velocity estimations. To improve data interpretation, we explore two complementary avenues: (1) explicitly account for the finite size of the transducers as part of the data interpretation/correction workflow, rather than assuming point sources, and (2) reducing the effective size of the transducers at the hardware design level. Both approaches as well as their combination have been tested successfully on multiple data sets including artificial homogeneous and isotropic samples as well as natural anisotropic rocks such as shales.
Hydrate Equilibrium Model for Gas Mixtures Containing Methane, Nitrogen and Carbon Dioxide
Sadeq, Dhifaf (University of Baghdad – Department of Petroleum Engineering) | Al-Fatlawi, Omar (University of Baghdad – Department of Petroleum Engineering) | Iglauer, Stefan (Edith Cowan University) | Lebedev, Maxim (Curtin University) | Smith, Callum (Curtin University) | Barifcani, Ahmed (Curtin University)
Abstract Gas hydrate formation is considered one of the major problems facing the oil and gas industry as it poses a significant threat to the production, transportation and processing of natural gas. These solid structures can nucleate and agglomerate gradually so that a large cluster of hydrate is formed, which can clog flow lines, chokes, valves, and other production facilities. Thus, an accurate predictive model is necessary for designing natural gas production systems at safe operating conditions and mitigating the issues induced by the formation of hydrates. In this context, a thermodynamic model for gas hydrate equilibrium conditions and cage occupancies of N2 + CH4 and N2 + CO4 gas mixtures at different compositions is proposed. The van der Waals-Platteeuw thermodynamic theory coupled with the Peng-Robinson equation of state and Langmuir adsorption model are employed in the proposed model. The experimental measurements generated using a cryogenic sapphire cell for the pressure and temperature ranges of (5-25) MPa and (275.5-292.95) K, respectively, were used to evaluate the accuracy of this model. The resulting data show that increasing nitrogen mole percentage in the gas mixtures results in decreasing of equilibrium hydrate temperatures. The deviations between the experimental and predictions are discussed. Furthermore, the cage occupancies for the gas mixtures in hydrate have been evaluated. The results demonstrate an increase in the cage occupancy for both the small and large cavities with pressure.
- Asia > Middle East (0.28)
- Europe > Norway > Norwegian Sea (0.25)
Frequency-dependent attenuation and dispersion caused by squirt flow: Three-dimensional numerical study
Alkhimenkov, Yury (University of Lausanne, University of Lausanne) | Caspari, Eva (University of Lausanne) | Gurevich, Boris (Curtin University, CSIRO) | Barbosa, Nicolás D. (University of Geneva) | Glubokovskikh, Stanislav (Curtin University) | Hunziker, Jürg (University of Lausanne, University of Lausanne) | Quintal, Beatriz (University of Lausanne, University of Lausanne)
ABSTRACT Seismic waves may exhibit significant dispersion and attenuation in reservoir rocks due to pore-scale fluid flow. Fluid flow at the microscopic scale is referred to as squirt flow and occurs in very compliant pores, such as grain contacts or microcracks, that are connected to other stiffer pores. We have performed 3D numerical simulations of squirt flow using a finite-element approach. Our 3D numerical models consist of a pore space embedded into a solid grain material. The pore space is represented by a flat cylinder (a compliant crack) whose edge is connected with a torus (a stiff pore). Grains are described as a linear isotropic elastic material, whereas the fluid phase is described by the quasistatic linearized compressible Navier-Stokes momentum equation. We obtain the frequency-dependent effective stiffness of a porous medium and calculate dispersion and attenuation due to fluid flow from a compliant crack to a stiff pore. We compare our numerical results against a published analytical solution for squirt flow and analyze the effects of its assumptions. Previous interpretation of the squirt flow phenomenon based mainly on analytical solutions is verified, and some new physical effects are identified. The numerical and analytical solutions agree only for the simplest model in which the edge of the crack is subjected to zero fluid pressure boundary condition while the stiff pore is absent. For the more realistic model that includes the stiff pore, significant discrepancies are observed. We identify two important aspects that need improvement in the analytical solution: the calculation of the frame stiffness moduli and the frequency dependence of attenuation and dispersion at intermediate frequencies.
Permeability inversion using induced microseismicity: A case study for the Longmaxi shale gas reservoir
Zhang, Yadong (China University of Petroleum (East China)) | Rezaee, Reza (Curtin University) | Müller, Tobias M. (Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Hohai University) | Zheng, Guangjie (Halliburton Energy Services Ltd) | Li, Jimmy X. (Curtin University) | Fan, Yu (PetroChina Southwest Oil and Gas Field Company) | Zeng, Bo (PetroChina Southwest Oil and Gas Field Company) | Zhou, Xiaojin (PetroChina Southwest Oil and Gas Field Company)
Abstract We have predicted the flow permeability and its spatial distribution for the Longmaxi shale gas reservoir using microseismicity induced during hydraulic-fracturing stimulation. In the time-of-occurrence versus distance-from-injector plot, we find that microseismic points exhibit a parabolic envelope, which we interpret as a triggering front. This reveals that fluid pressure diffusion is at least one of the underlying mechanisms of microseismicity generation. We derive the large-scale equivalent diffusivity from the triggering front plot and thereafter obtain a 3D diffusivity map of the heterogeneous reservoir by solving an eikonal-like equation suggested previously. During this process, we apply kriging interpolation to increase the density of sparsely distributed microseismic points. The resulting diffusivity ranges between 1.0 and with the peak probability attained at , which is consistent with the estimate we obtain from the triggering front analysis. We transform the diffusivity map into a permeability map using three different theories of fluid pressure diffusion in porous media: the seismicity-based reservoir characterization method (SBRC) based on Biot’s theory of poroelasticity, the quasirigid medium approximation (QRMA), and the deformable medium approximation (DMA) based on the de la Cruz-Spanos theory. The permeability according to QRMA is slightly higher than that from SBRC, yet we observe no significant difference. However, these estimates are by one order of magnitude higher compared with the permeability estimate from DMA. Furthermore, the permeability from all three theories is much higher than that from previously reported core sample measurements. We interpret this as the difference between large-scale equivalent and matrix permeability and therefore lend weight to the hypothesis that there exist highly conducting fluid pathways, such as natural fractures.
- North America (1.00)
- Asia > China > Sichuan Province (0.49)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock > Shale (1.00)
- Geology > Geological Subdiscipline > Geomechanics (0.93)
- North America > United States > Texas > Fort Worth Basin > Barnett Shale Formation (0.99)
- North America > Canada > British Columbia > Western Canada Sedimentary Basin > Alberta Basin > Montney Formation Field > Montney Formation (0.99)
- North America > Canada > Alberta > Western Canada Sedimentary Basin > Greater Peace River High Basin > Pouce Coupe Field (0.99)
- (2 more...)
Numerical Simulation of Gas Lift Optimization Using Genetic Algorithm for a Middle East Oil Field: Feasibility Study
AlJuboori, Mustafa (Curtin University) | Hossain, Mofazzal (Curtin University) | Al-Fatlawi, Omar (University of Baghdad-Department of Petroleum Engineering) | Kabir, Akim (Saudi Aramco) | Radhi, Abbas (Missan Oil Company)
Gas-lift technique plays an important role in sustaining oil production, especially from a mature field when the reservoirs’ natural energy becomes insufficient. However, optimally allocation of the gas injection rate in a large field through its gas-lift network system towards maximization of oil production rate is a challenging task. The conventional gas-lift optimization problems may become inefficient and incapable of modelling the gas-lift optimization in a large network system with problems associated with multi-objective, multi-constrained, and limited gas injection rate. The key objective of this study is to assess the feasibility of utilizing the Genetic Algorithm (GA) technique to optimize the allocation of the continuous gas-lift injection rate in a network system of a Middle Eastern oil field with 43 gas-lift injected wells through numerical modelling and simulation studies. Reservoir pressure and water cut sensitivity studies are performed to investigate the potential impacts of these parameters on well production performance and production life cycle of the field. Sample economics analysis are exercised to broaden the understanding of potential benefit of the implementation gas lift techniques in the field from both technical and economic viewpoint. In addition, while application of GA is not a new idea, this paper elaborates the GA based optimization techniques for improving the oil production rate by implementing gas lift in a large Middle Eastern oil field. The optimization model is presented step by step, so it can easily be followed, and be used as a guide, especially by frontline production engineers involved in designing and development of gas-lift system towards optimally allocation of gas injection rate to individual well in a network system for a field with limited gas injection rate.
- North America > United States (1.00)
- Asia > Middle East > Iraq > Diyala Governorate (0.44)
- South America > Brazil > Rio de Janeiro > South Atlantic Ocean > Campos Basin > Marlim Field > Macae Formation (0.99)
- South America > Brazil > Rio de Janeiro > South Atlantic Ocean > Campos Basin > Marlim Field > Lago Feia Formation (0.99)
- Europe > United Kingdom > North Sea > Northern North Sea > East Shetland Basin > Block 211/28 > North West Hutton Field > Brent Group Formation (0.99)
- (2 more...)