Influence Of Mineral Composition Research Articles

Impact of rock heterogeneity on reactive flow during acid stimulation process

Acid stimulation within carbonate rocks represents a crucial aspect of reactive flow applications in subsurface porous media and has been widely used in carbonate reservoir development attributed to its rapid effectiveness and cost-efficiency. This study is motivated to investigate further the impact of rock heterogeneity on the acid stimulation process. The two-scale continuum model is employed for capturing mass, momentum, and energy transfer during the acid stimulation process. The core-scale model is expanded to consider the specific composition of solid minerals, including reactive minerals such as calcite and dolomite and non-reactive ones like quartz and clay. A heterogeneity generator is developed by coupling with the open-source geostatistical program to produce different heterogeneous parameters using random seeds with varying spatial correlation lengths. Sensitive cases are performed to present an investigation into the influence of mineral composition and matrix heterogeneity on the acid stimulation process. Results show that the typical results of acid stimulation are closely tied to different heterogeneity conditions. The optimum conditions for acid stimulation are sensitive to the concentration of reactive components. The optimum acid injection rate declines as dolomite content increases, while the corresponding acidizing breakthrough volume reduces with higher calcite levels. The presence of mineral layers, especially in horizontal distributions, complicates acid fluid efficiency due to the competitive reaction between calcite and dolomite. Compared to the heterogeneous distribution of minerals, matrix heterogeneity plays a critical role in acid fluid consumption efficiency. Increasing heterogeneity leads to significant reductions in breakthrough volumes, largely governed by the correlation length.

Influence of Mineral Composition on Initiation Pressure of Waterflood-Induced Fractures in Tight Sandstone Reservoir.

Revealing the impact of core mineral composition on the initiation pressure of waterflood-induced fractures (WIFs) in tight sandstone reservoirs is a crucial aspect of studying the initiation mechanism of WIFs. In this paper, through quantitative characterization of the core mineral composition from six samples of the Chang 6 reservoir in the Wuqi oilfield, western Ordos Basin, and modified experimental cores and displacement equipment for WIF experiments, the influence of the core mineral composition on the initiation pressure of WIFs in tight oil reservoirs is investigated. The conclusions are as follows. (1) The rock mineral composition of the Chang 6 reservoir in the Wuqi oilfield, western Ordos Basin, includes quartz, feldspar calcite, and clay, characterizing it as a typical feldspar sandstone reservoir. Quartz and calcite are considered as brittle minerals, while feldspar and clay are categorized as lithologic minerals. (2) For feldspar sandstone reservoirs, including quartz, feldspar, calcite, and clay minerals, when the combined content of quartz and feldspar exceeds 600% of the total mineral content, the changes of quartz and feldspar content will affect the initiation pressure of WIFs. As the ratio of the quartz content to feldspar content Rqf increases, the initiation pressure of WIFs exhibits a logarithmic function decrease. (3) Considering the contribution of diagenetic minerals to rock brittleness, the calculation method for the brittleness index of feldspar tight sandstone reservoirs is improved. (4) The relationships between Rqf, brittleness index, and initiation pressure of induced fractures suggest that an increase in Rqf leads to a power-law increase in the brittleness index, while the initiation pressure of WIFs relative to the brittleness index shows a power-law decrease. This phenomenon indicates an increased likelihood of WIFs occurring during the long-term water injection process in feldspar sandstone reservoirs. This work contributes to understanding how core minerals affect the initiation pressure of WIFs in tight sandstone reservoirs.

Influence of Mineral Composition on Rock Mechanics Properties and Brittleness Evaluation of Surrounding Rocks in Soft Coal Seams

Influence of Mineral Composition on Rock Mechanics Properties and Brittleness Evaluation of Surrounding Rocks in Soft Coal Seams

Influence of mineral composition on thermal equilibrium state during laser perforation

Energy consumption during laser rock perforation is controlled by conductive losses and latent heats during the phase transitions of melting and evaporation. To understand then improve the efficiency of laser perforation, the influence of rock mineral composition on these processes is investigated, and a theoretical model of laser rock breaking under steady-state heat conduction is developed. The findings reveal that the melting properties of mineral components primarily control thermal equilibrium during laser perforation. The key minerals, namely feldspar, quartz, and clay, were used to study the melt response in both pure samples and synthetic rock composites composed of these minerals. When feldspar is dominant, the thermal equilibrium temperature remains stable after reaching the feldspar gas phase boundary. While in situations where quartz dominates, the thermal equilibrium temperature is slightly below the melting point of pure quartz. The findings highlight the relationship between laser rock perforation efficiency and melting properties of minerals.

Study on the influence of mineral composition on the mechanical properties of granite based on FDEM-GBM method

The macroscopic mechanical properties and crack propagation of rocks are significantly affected by the micro-scale heterogeneity of rocks. In this study, a two-dimensional tensile/shear fracture model to simulate the nonlinear behavior of grain boundaries through a combined finite-discrete element method based on the grain model (FDEM-GBM). The purpose of this model was to investigate the effects of mineral composition on rock mechanical properties and fracture extension. To calibrate the micromechanical parameters of the cohesive elements within the numerical rock model, the Plackett–Burman design and response surface method were employed. Furthermore, the study analyzed the effects of different mineral compositions on the macro-mechanical characteristics of rocks and attempted to interpret the results from the perspective of fracture evolution. The results demonstrated that the PB design-response surface design-iterative optimization method successfully enabled the calibration of the required microscopic parameters in the FDEM-GBM model. Under uniaxial compression loading, damage primarily occurred inside the crystal, with a dominant mode of tensile failure at the stress peak. Additionally, an increase in feldspar mineral content generally led to a decreasing trend in the uniaxial compressive strength and elastic modulus of the rock model. This changing pattern may be associated with the greater presence of internal cracks within feldspar minerals and relatively fewer cracks in quartz minerals.

Influence of Mineral Composition on Properties and Integrated Processing Prospects of Ferruginous Bauxite

Influence of Mineral Composition on Properties and Integrated Processing Prospects of Ferruginous Bauxite

Influence of mineral composition on nano-interfacial adhesion of asphalt mixtures exposed to chloride salt erosion

As a common pavement deicing salt, sodium chloride has adverse effects on asphalt pavement. In this study, molecular modeling methods were used to analyze the effects of mineral composition and chloride salt erosion on the interfacial adhesion properties of asphalt-aggregate composites. Four representative asphalts (AAA-1, AAK-1, AAM-1, and AAF-1), three representative minerals (α-quartz, calcium carbonate, and alumina), and sodium chloride solutions were selected to model the asphalt-aggregate composites exposed to chloride salt erosion. The effects of asphalt type, mineral composition, salt concentration, and erosion temperature on the interface adhesion of the asphalt mixture were considered. The chloride salt erosion resistance of the four components and asphalt molecules were further analyzed. The simulation results indicate that the effect of erosion temperature on the interfacial adhesion performance is minor. The interfacial adhesion decreased with the increase in chloride salt concentration. Alkaline minerals are more susceptible to chloride salt erosion, followed by neutral and acidic minerals. The adhesion energies of resin and aromatic decreased most significantly in alkaline minerals, followed by neutral minerals, and the least decreased in acidic minerals exposed to chloride salt erosion. Asphalt molecules with more aromatic rings, shorter alkyl side chains, and stronger polarity have strong resistance to chloride salt erosion and can form strong adsorption with the active sites on the mineral surface. However, asphalt molecules with long-chain alkanes, fewer aromatic rings, or longer alkyl side chains are difficult to resist chloride salt erosion.

Influence of Mineral Composition on Properties and Integrated Processing Prospects of Ferruginous Bauxite

Influence of Mineral Composition on Properties and Integrated Processing Prospects of Ferruginous Bauxite

Microbially induced calcite precipitation and synergistic mineralization cementation mechanism of Pisha sandstone components

Soil erosion is a key problem of erosion in Pisha sandstone areas, and microbially induced calcium carbonate deposition is a bioconsolidation technique with soil improvement potential. There is more limited information available on the uniformity of the distribution of microbially induced calcium carbonate precipitation mediated by Pisha sandstone grains and on the influence of mineral composition on calcium carbonate bonding mechanisms. In this study, the curing mechanism of Pisha sandstone particles under the microbially induced calcium carbonate deposition technique was investigated by unconfined compressive strength tests, X-ray diffraction spectroscopy, scanning electron microscopy, Fourier transform infrared spectroscopy and thermogravimetric analysis. The results showed that the self-adsorption biphasic injection method was effective in regulating the homogeneous distribution of microorganisms, and the addition of an additive solvent promoted the homogeneous distribution of bacteria, but the contribution to the mechanical properties was not obvious when urea was used as an additive solvent. The analysis revealed that montmorillonite on the surface of Pisha sandstone particles had an adsorption effect on the bacteria. In addition, the microorganisms induced the transformation of the montmorillonite phase to the illite phase during the biological treatment. Combined Fourier transform infrared spectroscopy and thermogravimetric analysis revealed that the CO bond in biogenic calcium carbonate, the SiO bond in Pisha sandstone particles, undergoes intermolecular hydrogen bonding under the modulating effect of the metabolites of microorganisms, and the anionic coordinating group of the extracellular polymer can form a stronger electrostatic interaction with calcium ions, requiring more energy for decomposition. This work provides a case study of microbially induced calcite deposition to improve loose Pisha sandstone, and at the same time, it is not difficult to see how Pisha sandstone particles, as weakly cemented sands, could be a suitable vehicle for a potential microbial consolidation process.

Distribution characteristics and oil mobility thresholds in lacustrine shale reservoir: Insights from N2 adsorption experiments on samples prior to and following hydrocarbon extraction

The pore structure and oil content of shales have an important influence on the oil mobility and enrichment. In this study, the lacustrine shale samples from the Qingshankou Formation (Q1) of Songliao Basin were selected. TOC, pyrolysis, XRD and nitrogen adsorption were performed on the original and extracted shale samples. Then the influence of mineral composition and organic matter (OM) on the development of nano-scale pore, the oil phase states and mobility were analyzed. The Q1 shale samples can be sub-divided into three types according to the isotherm characteristics. Type A samples are characterized by high kerogen content, with oil mainly existing in the free phase state. Type B samples are characterized by medium kerogen content, oil mainly exists in the absorbed phase state. Type C samples are characterized by low kerogen content, with trace oil found in the absorbed phase state. Nano-scale organic pores are well developed in the Q1 Formation. Oil is primarily found in the pore spaces with diameters less than 10 nm, this being the pore size threshold for mobile shale oil. When TOCo > 2.0 wt% and EOM >1.0 wt%, Q1 Formation shale oil mobility is high, resulting in prospective drilling targets.

Characteristics and Main Controlling Factors of Fractures within Highly-Evolved Marine Shale Reservoir in Strong Deformation Zone

Based on the systematical observations of cores, thin sections, and scanning electron microscope (SEM) sections, together with the testing data and characteristic parameters, this paper discussed the characteristics and controlling factors of fractures, and their control on shale gas accumulation in the Lower Cambrian Niutitang Formation black shale reservoir of Well YX1 in the northern Guizhou Province. The results show that macro structural fractures are common in the Niutitang Formation, which can be divided into shear fractures (e.g., high dip-angle shear fractures and low dip-angle slip fractures), tensional fractures, and tension-shear fractures. Non-structural fractures in microfractures can be divided into organic-related fractures and inorganic mineral-related fractures. Most of the structural fractures were filled and the types of fillings are diverse. The staggered relationships of fractures confirm the complexity of tectonic movement in the study area. The formation of structural fractures in Well YX1 is mainly controlled by the major fault. The influence of mineral composition and content, mechanical properties, brittleness, and organic matter content of rocks on the characteristics of the fractures are from the external manifestation of sedimentary environment. Affected by diagenetic evolution, organic matter-related fractures are not common. Compared with other shale gas reservoirs in China and abroad, the organic-rich shale reservoir of Well YX1 is characterized by both “geological sweet spots” and “engineering sweet spots”; however, strong deformation and faulting have led to the loss of shale gas and damage of the overpressure environment. Therefore, it is suggested that small-scale fractures, caused by tectonic movements but without large penetrating faults, are the most favorable for shale gas reservoirs. Based on the complicated tectonic setting in northern Guizhou, the formation pressure should be taken into account.

Pore development in terrestrial shale reservoirs: the Permian Lucaogou Formation, Junggar Basin, northwestern China

Pore structure is the key factor in determining the development potential of shale reservoirs with a need for more research into mechanisms of pore system development in terrestrial shales. In this study, the pore structure and control mechanisms of typical terrestrial shale reservoirs were described by investigating porosity and permeability under overburden pressure, mercury injection capillary pressure, N2 adsorption, rock pyrolysis analysis, geochemistry and scanning electron microscopy. The results show that: (1) the main pore types in the upper section are quartz and clay intergranular pores, whereas those in the lower section are ferroan dolomite, plagioclase and quartz intergranular pores; (2) clay minerals control the intra-layer pore structure, and quartz minerals control the interlayer pore structure in the upper section, whereas ferroan dolomite provides the largest micron-scale pore size in the lower section; and (3) the micropores of samples with low organic matter content peak at the low maturation stage, whereas the micropores of samples with high organic matter content show an increasing trend from immature to mature stages. The influence of mineral composition and thermal maturity on the development of pore systems in shale reservoirs is an important indicator for future exploration in terrestrial shales. Key points Factors influencing pore type of a typical terrestrial shale reservoir in the Permian Lucaogou Formation of the Jimsar Depression are inorganic minerals (quartz, ferroan dolomite and clays) and organic matter. Thermal maturity, which controls the development of organic nanopores, peaks at the beginning of the oil window. The pore system in terrestrial shale reservoirs comprises inorganic minerals that control primarily porosity and mature organic matter that control secondary porosity formed during late diagenesis.

Mathematical modeling of pyroxene-magnetite crystalline shales elastic and acoustic properties

The analysis of the results of mathematical modeling of the influence of the format, mineral concentration and fracture of metamorphic crystalline shales of the Pishcha iron ore structure is presented. The aim of this work is to analyze the influence of mineral composition, types, orientation and concentration of mineral inclusions and microcracks on the acoustic and elastic properties of a group of samples of “quartz-magnetite-pyroxene” crystalline shales of Pishchans’ka iron ore structure. Based on the method of conditional moments, mathematical modeling of the influence of the format, orientation and content of mineral grains, as well as the concentration and format of cracking on the acoustic and elastic properties of rocks of the Pishchans`ka iron ore structure was performed. According to the obtained data, a weak effect of changes in the content of rock-forming minerals and a significant effect of different types of fractures on the value of elastic and acoustic anisotropy (10-40%) was proved. Elastic constants of models with layered and chaotic orientation of structural-textural elements are calculated. It is established that most models, as well as basic samples have a rhombic type of acoustic symmetry. When comparing the stereoprojections of the anisotropy parameters of real samples with the stereoprojections obtained during modeling, the authors found that in most samples there is a double system of cracking: chaotic and directed in the area of shale. The results of mathematical modeling showed that for models with ordered crack orientation, the change in the format and concentration of voids is a defining characteristic. This effect is significantly smaller for models with a chaotic arrangement of structural elements. It is proved that models with a combined (layered and chaotically oriented) type of fracture are the closest to real samples. The authors show that this technique allows you to create and operate models close to the real geological environment.

Influence of Mineral Composition in Natural Granite Rocks on Microhardness

Granites are becoming increasingly popular and, as a result, their areas of use are expanding. In addition to their colour and particle size, the surface roughness of the machined material is becoming an important aspect of their application. In order to create a suitable surface roughness, the type of rocks located on the surface, elemental composition and microhardness of the minerals are important, because knowledge of these characteristics can be used to determine the machining parameters. Microhardness is affected by the atomic percentage values of Si, Al and Na. In addition, for some minerals, a correlation can also be established between the Si, Al and Na components.

Influence of Mineral Compositions on Shale Pore Development of Longmaxi Formation in the Dingshan Area, Southeastern Sichuan Basin, China

Influences of the characteristics of organic matters and mineral compositions on the development of shale microscopic pores were discussed through performing low-temperature nitrogen adsorption, whole-rock “X” diffraction, and field emission scanning electron microscope on black organic-rich shale samples of Longmaxi Formation in the Dingshan area, southeastern Sichuan Basin, in combination with the characteristics of shale organic matters. The shale in the Dingshan area has complex mineral composition, which is mainly quartz and clay minerals. Both contents range from 23% to 72% and 36% to 70%, respectively. The vertical variation is obvious, and there are few feldspar and carbonate rocks; the pyrite content is more than 2%. The bottom shale has high brittleness and gradually decreases in the vertical direction. The brittleness index is between 0.481 and 0.627 and is concentrated above 0.5. It shows strong compressibility and is easy to form a complex network system in hydraulic fracturing. Quartz and feldspar mainly provide secondary dissolved pores, intercrystalline mineral pores, and nanoedge gaps in contact with organic matter. They have no obvious correlation with the specific surface area of shale but have a weak correlation with pore volume. They mainly control the development of macropores. Organic matter develops many hydrocarbon-generating pores, which strongly correlate with the specific surface area and a weak correlation with pore volume. It mainly controls the development of micromesopores. Clay minerals mainly provide a large number of interlaminar pores and interlayer fractures in the clay. The intergranular pores of clay and clay have a weak correlation with pore volume and specific surfaces. They contribute to the development of shale micropores, mesopores, and macropores. Pyrite mainly provides intercrystalline pores and mold pores. By restricting the interaction with organic matter, the development of shale pores is promoted within a certain content range. When the content exceeds this range, the development of micropores is inhibited. The conversion threshold in the Dingshan area is 5.0%.

Dynamic Brittle Instability Characteristics of 2000 m Deep Sandstone Influenced by Mineral Composition

The study of dynamic brittleness and failure characteristics is of guiding significance for promoting the full exploitation and utilization of deep sandstone reservoirs. At present, there have been more comprehensive studies on the mechanical properties of deep sandstone reservoirs, but the study of mineral composition on the dynamic brittleness and failure characteristics of deep sandstone reservoirs is relatively weak. In this paper, XRD mineral composition analysis, uniaxial compression experiment, and Brazilian splitting are used to study the influence of mineral composition on mechanical properties and failure characteristics of deep sandstone reservoirs. It was concluded that (1) the mineral compositions of deep sandstone reservoirs are mainly three kinds of oxides: SiO2, Al2O3, and CaO. The failure modes of deep sandstone reservoir samples under uniaxial compression are more complicated, with tension failure and shear failure each accounting for half. In the Brazilian split test, the failure modes of sandstone samples are mainly shear failure. (2) The compressive strength decreases obviously with the increase of CaO content. The contents of SiO2, Al2O3, and CaO all have a great influence on the residual strength of deep sandstone reservoirs. The deformation modulus decreases gradually with the increase of Al2O3 content. (3) The brittleness increases slightly when the content of SiO2 increases, while the brittleness decreases slightly when the content of Al2O3 increases. Considering factors such as strength, modulus, brittleness, and failure characteristics, SiO2 content has the greatest influence on the mechanical properties of deep sandstone reservoirs, followed by Al2O3 content, and CaO content has the least influence. The research results have a guiding role in the utilization and development of oil and gas resources in deep sandstone reservoirs and promote oil and gas development from the middle to deeper layers.

Rheological study on influence of mineral composition on viscoelastic properties of clay

Using an oscillating shear rheology experiment and zeta potential analysis to explore the influence of mineral composition on the viscoelastic properties of soil, three pure mineral clays, namely, kaolin, montmorillonite, and illite, and their mixed simulated clays were tested. The results showed that the influence of mineral composition on the viscoelastic properties was larger than the influence of other factors. The contribution of montmorillonite to the viscoelastic properties was much greater than that of kaolin or illite. The influence of the coefficient of montmorillonite on the viscoelasticity of the simulated soil decreased with increase of strain and water content. The zeta potential test results were consistent with theoretical analyses.

The influence of the rock mineralogy on population density of Chthamalus (Crustacea: Cirripedia) in the Ligurian Sea (NW Mediterranean Sea)

Settlement, recruitment and survival of sessile marine species are driven by many biotic and abiotic factors. Among them, substrate mineral composition is generally a neglected topic, despite it proved to be a relevant contributing variable in driving the structure of benthic communities. Thanks to their ecology, Chthamalus species are a good proxy to test the role of substrate in affecting settlement and final population density on exposed rocky shores. Differences in the number of individuals were analysed in eight localities along the Eastern Ligurian Riviera (north-western Mediterranean Sea), from Portovenere to Manara Cape. In this sector of the Ligurian littoral, the coast is constituted by different rocks characterised by variable concentrations of calcite, silicates and quartz. This situation constitutes an ideal setting to evaluate the influence of mineral composition of the rocks in structuring the epilithic macrobiota communities in energetic splash zones and under similar physical pressures. Rocks rich in calcites turned out to be more suitable for Chthamalus species than substrates containing high amounts of silicates, and of quartz in particular. Additionally, also the grain size of the main mineral component of the rocks, determining in turn the surface roughness seemed to influence barnacle densities, with a significant preference for finer-grained substrates.

Influence of mineral compositions on properties of KTa1-xNbxO3 single crystals grown by top-seeded growth solution method

Potassium tantalate niobate KTa1-xNbxO3 (KTN) single crystals with different x values (x = 0, 0.25, 0.37 and 0.45) were grown by a top-seeded growth solution method in a KTa1-xNbxO3 solid-solution system. The crystalline structure, optical and dielectric properties were investigated experimentally using X-ray diffraction, spectrophotometer and LCR meter, respectively. The compositions were measured by electron probe microanalysis. The band gap energy was calculated based on the optical transmittance spectra. The XRD results indicated that the single crystals exhibited cubic structure (x ≤ 0.37) and tetragonal phase (x = 0.45) at room temperature. The absorption properties demonstrated that the absorption coefficients and the band gap energy decreased with the increasing Nb component. The dielectric results indicated that the Curie point increased depending on the increasing Nb component.

ВЛИЯНИЕ МИНЕРАЛЬНОГО СОСТАВА ПИТАТЕЛЬНОЙ СРЕДЫ НА РОСТ SATUREJA HORTENSIS L. В КУЛЬТУРЕ IN VITRO

ВЛИЯНИЕ МИНЕРАЛЬНОГО СОСТАВА ПИТАТЕЛЬНОЙ СРЕДЫ НА РОСТ SATUREJA HORTENSIS L. В КУЛЬТУРЕ IN VITRO