Geoenergy Science and Engineering最新文献

{"title":"Investigation of bio-based chelating agents to prevent and remove mineral scales caused by mixing of incompatible brine water: An insight into molecular characterization and active forces","authors":"Saeed Karami ,&nbsp;Arezoo Rezaei ,&nbsp;Mohsen Rahmati ,&nbsp;Azam Motaghi ,&nbsp;Mohsen Sepehr","doi":"10.1016/j.geoen.2025.213947","DOIUrl":"10.1016/j.geoen.2025.213947","url":null,"abstract":"<div><div>Scaling is one of the problems that challenge smart water injection due to damage to reservoir porous media and causing wellbore skin. To alleviate this problem, six bio-based chelating agents were extracted from the waste of Glycyrrhiza glabra, Maple, Morus nigra, Eucalypt, Zyziphus spina Christi, and Platanus leaves to be used as scale inhibitors and removal for CaSO₄ and SrSO₄ salts. After characterizing the chelating agents via FTIR technique, HNMR spectroscopy, zeta potential, and CMC calculation, they were used in static inhibition and removal tests. According to the static tests, the chelating agents inhibited 85.7–95.8 % of the scale formation, and 29.7–85.9 % of the precipitated scales were removed by using them. Ion chromatography of filtrated water was investigated to cation (Sr²⁺ and Ca²⁺) concentrations. The higher removal/inhibition efficiency was explained by the higher concentration of potential precipitating cations. The highest strontium and calcium concentration was observed in the sample inhibited by the chelating agent extracted by Glycyrrhiza glabra leaf waste, and on the next level, the agent extracted by maple waste. A comparison of static tests and characteristic indexes, which were given by the FTIR and HNMR techniques, showed that two mechanisms of electrostatic attraction and cation–π interaction are responsible for scale inhibition and removal. In other words, agents with more polar functional groups (such as O-H bonds) and electron-rich π compounds (such as alkenes and aromatic rings) are more feasible for inhibition and removal of scales. The adsorption of chelating agents was also studied to see their retention on reservoir rock. The adsorption of chelating agents on CaCO₃ powders was in the range of 11.2–19.2 mg/g, while their ultimate adsorption on SiO₂ was in the range of 7–10.3 mg/g. The higher adsorption potential of chelating agents was consistent with polar indexes, such as the alcoholic index of the FTIR technique, representing the fact that electrostatic interaction is the main intermolecular interaction for adsorbing chelating agents on the rock. Regarding the feasibility of economic waste-derived chelating agents for both scale inhibition and removal, a promising future is anticipated for using them in water injection projects.</div></div>","PeriodicalId":100578,"journal":{"name":"Geoenergy Science and Engineering","volume":"252 ","pages":"Article 213947"},"PeriodicalIF":0.0,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143892091","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}

{"title":"CO2 huff-n-puff in shale cores: Live-oil vs. dead-oil","authors":"Yujia Guo,&nbsp;Yue Shi,&nbsp;Kishore Mohanty","doi":"10.1016/j.geoen.2025.213942","DOIUrl":"10.1016/j.geoen.2025.213942","url":null,"abstract":"<div><div>Oil recovery in shale oil reservoirs by depressurization produces less than 10 % of the original oil in place (OOIP). Cyclic gas injection or huff-n-puff (HnP) is a promising EOR process for unconventional reservoirs. Most of the existing experimental works on huff-n-puff have been performed with dead-oil instead of live-oil. The dissolved gas in the live-oil can play a critical role in the huff-n-puff process. The goal of this paper is to compare the gas huff-n-puff process in shale cores using both live-oil and dead-oil. In our experiments, the live-oil was generated in situ by diffusing methane into dead-oil saturated cores. After live-oil generation, primary recovery and CO₂ huff-n-puff experiments were conducted sequentially. Oil recovery was obtained through core mass measurement, produced liquid analysis, and T₂ NMR inspection. Produced oil and gas compositions were analyzed by gas chromatography. A new analytical solution was proposed to model the pressure decline during the methane diffusion process to estimate the gas diffusion coefficient in oil-saturated porous media. Results indicate that a live-oil with a GOR of 402.6 SCF/STB was generated within the core. The diffusion coefficient of methane in an oil-saturated core was measured to be 4.52 × 10⁻¹⁰ m²/s. In the live-oil test, 8 % OOIP was recovered in primary recovery, the one cycle CO₂ HnP recovered an additional 32 % OOIP. In contrast, the dead-oil test results in 5 % OOIP in primary recovery and 19 % OOIP in the CO₂ huff-n-puff. The live-oil experiment shows higher oil recovery because the compressibility of live-oil allowing gas to enter the matrix through both convection and diffusion. However, in the dead-oil experiment, the lack of compressibility limits gas penetration to only diffusion, resulting in lower recovery. In field-scale, gas flow driven by convection would be more significant compared to core-scale.</div></div>","PeriodicalId":100578,"journal":{"name":"Geoenergy Science and Engineering","volume":"252 ","pages":"Article 213942"},"PeriodicalIF":0.0,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143894466","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}

{"title":"Experimental and numerical simulation studies on sweep efficiency in electrical heating-CO2 assisted SAGD for heavy oil reservoirs with interbeds","authors":"Shuxian Li ,&nbsp;Chao Wang ,&nbsp;Yongbin Wu ,&nbsp;Peng Liu ,&nbsp;Xiaokun Zhang ,&nbsp;Pengcheng Liu ,&nbsp;Changfeng Xi ,&nbsp;Qiang Wang ,&nbsp;Jipeng Zhang","doi":"10.1016/j.geoen.2025.213941","DOIUrl":"10.1016/j.geoen.2025.213941","url":null,"abstract":"<div><div>Dual horizontal well steam-assisted gravity drainage (SAGD) technology is an effective method for developing heavy oil reservoirs. However, heterogeneous factors often result in uneven steam chamber development that such as interlayers in the reservoir, which ultimately lower the sweep efficiency. This paper focused on electrical heating-CO₂ assisted SAGD in Xinjiang oilfields in China to enhance both sweep efficiency and overall recovery in heavy oil reservoirs. It was investigated that the mechanisms and technical potential of electrical heating and CO₂ in the preheating initiation and development production processes of SAGD. Three-dimensional physical experiments and numerical simulations were used to determine the best preheating methods and key parameters. The results showed that the intermittent heating and intermittent CO₂ injection yielded the best transfer effects and sweep outcomes. Electrical heating induces micro-fractures in interbeds to establish oil drainage channels, while CO₂ enriches at the edges of the steam chamber, dissolving to reduce viscosity and expanding the operational range by 6.8 %. The integrated technology achieves an ultimate recovery rate of 62 %, representing a 23.6 % improvement over conventional SAGD, alongside a 9.1 % reduction in cumulative steam injection and an enhanced cumulative oil-to-steam ratio of 0.35, with significantly more uniform residual oil saturation distribution. By optimizing the vertical uniformity of steam chamber expansion and extending the stable production period, this approach provides an innovative pathway for efficient development of heavy oil reservoirs with interbeds.</div></div>","PeriodicalId":100578,"journal":{"name":"Geoenergy Science and Engineering","volume":"252 ","pages":"Article 213941"},"PeriodicalIF":0.0,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143907666","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}

{"title":"Study on multiphase flow behavior and parameters for CO2 storage in depleted oil and gas reservoirs","authors":"Bing Wu ,&nbsp;Zijiang Yang ,&nbsp;Congyue Liu ,&nbsp;Yu Shi ,&nbsp;Xiaoyan Zhao ,&nbsp;Yao Liang ,&nbsp;Xiaobo Tang","doi":"10.1016/j.geoen.2025.213949","DOIUrl":"10.1016/j.geoen.2025.213949","url":null,"abstract":"<div><div>In CO₂ storage within depleted oil and gas reservoirs, the primary focus is on increasing production, aiming to achieve higher oil recovery with the least amount of CO₂ injection, which contradicts the purpose of carbon storage. The research on improving the performance of CO₂ enhanced oil recovery and storage has not addressed the optimization of CO₂ migration range, neglecting the impact of CO₂ migration on injection and well placement design. This article aims to improve the CO₂ storage and migration as the primary objective, establishing a three-phase seepage-heat transfer coupling numerical model, revealing the fluid distribution patterns in reservoir. Comparing the effects of injection and well parameters on CO₂ storage capacity, oil recovery and CO₂ migration. The results indicate that low-temperature and high-speed injection is beneficial for CO₂ storage, increasing well spacing is advantageous for CO₂ migration, and horizontal wells should be preferred during well placement, followed by the up-injection down-production 3 wells pattern. On the basis, multi-objective optimization is carried out for CO₂ storage capacity, oil recovery and CO₂ migration range. In research conditions, with the same amount of CO₂ injected, the storage capacity and migration range increase by 95.2 % and 12.1 %, respectively, while the decline in oil recovery is effectively mitigated. This study expected to provide a theoretical basis for CO₂ storage in depleted oil and gas reservoirs.</div></div>","PeriodicalId":100578,"journal":{"name":"Geoenergy Science and Engineering","volume":"252 ","pages":"Article 213949"},"PeriodicalIF":0.0,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143888092","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}

{"title":"Occurrence states and transport behavior of crude oil in different permeability oil reservoirs during depletion development","authors":"Xiliang Liu ,&nbsp;Hao Chen ,&nbsp;Weiming Cheng ,&nbsp;Yang Li ,&nbsp;Yao Zhao ,&nbsp;Yangwen Zhu ,&nbsp;Hongbo Zeng","doi":"10.1016/j.geoen.2025.213944","DOIUrl":"10.1016/j.geoen.2025.213944","url":null,"abstract":"<div><div>The fluid occurrence states exert a significant influence on the crude oil development. Previous studies relied on unrealistic formation fluid models and assumptions, resulting in imprecise methods for determining fluid occurrence states. Moreover, limited research has addressed the different oil reservoir types on occurrence states and transport behaviors during the depletion development process. This study establishes a precise characterization method for three fluid occurrence states: free fluid (FF), capillary-bound fluid (CAF), and clay-bound fluid (CBF). The transport behavior of these occurrence states under various depletion development conditions is analyzed comprehensively. Results indicate that the accuracy of identifying different occurrence states improves by 11.5 %–34.0 % using the modified approach. Variations in pore diameter and clay mineral content result in a 4.5 %–24.3 % higher proportion of FF in low permeability reservoirs compared to ultra-low permeability and tight oil reservoirs, while CAF and CBF proportions are greater in the latter. During the depletion development process, FF is mobilized first, followed by a smaller amount of CAF, while CBF remains undeveloped. The factors influencing reservoir depletion development are ranked in order of significance as follows: production pressure difference, Z factor, fluid viscosity, pressure reduction rate, and pressure reduction pattern.</div></div>","PeriodicalId":100578,"journal":{"name":"Geoenergy Science and Engineering","volume":"252 ","pages":"Article 213944"},"PeriodicalIF":0.0,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143881629","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}

{"title":"Damage behavior and constitutive model of cement sheath under alternating temperature","authors":"Niantao Zhou ,&nbsp;Kuanhai Deng ,&nbsp;Yuanhua Lin ,&nbsp;Kai Yan ,&nbsp;Changlin Li ,&nbsp;Pengjie Wang ,&nbsp;Pengfei Xie","doi":"10.1016/j.geoen.2025.213945","DOIUrl":"10.1016/j.geoen.2025.213945","url":null,"abstract":"<div><div>In this paper, an evaluation method for the mechanical properties of cement sheath is proposed to describe the real mechanical damage behavior of cement sheath under alternating temperatures. The mechanical properties of cement sheath under three types of alternating temperatures (25 °C–150 °C, 25 °C–200 °C, and 25 °C–250 °C) are investigated by using the full-scale experiment device of “production casing-cement sheath-intermediate casing” system, by which the damage law and mechanism of mechanical properties for cement sheath under alternating temperatures is revealed. Based on the test results, the uniaxial and triaxial damage constitutive models under alternating temperatures are established for future finite element simulations, and experimental results verify their reliability. The results show that the alternating temperature significantly damages the mechanical properties of the cement sheath, including the peak stress, elastic modulus, pore strain, elastic strain, and plastic strain. The damage mechanism under alternating temperatures includes thermal damage caused by uncoordinated thermal expansion of particles inside the cement sheath and free water evaporation, and additional damage resulting from inconsistent thermal expansion between the casing and the cement sheath, plastic accumulation and fatigue damage caused by alternating load, and chemical damage induced by changes in chemical substances. The research results could provide a reference and basis for cement sheath integrity theory in heavy oil wells.</div></div>","PeriodicalId":100578,"journal":{"name":"Geoenergy Science and Engineering","volume":"252 ","pages":"Article 213945"},"PeriodicalIF":0.0,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143892089","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}

{"title":"A novel hybrid enhanced oil recovery: Nanosmart water with amphoteric surfactant for advancing fluid-fluid and rock interactions","authors":"Gadis Wahyu Ramadhani ,&nbsp;Syahrir Ridha ,&nbsp;Iskandar Dzulkarnain ,&nbsp;Astra Agus Pramana ,&nbsp;Muhammad Hammad Rasool","doi":"10.1016/j.geoen.2025.213937","DOIUrl":"10.1016/j.geoen.2025.213937","url":null,"abstract":"<div><div>Enhanced oil recovery (EOR) techniques are vital for maximizing hydrocarbon extraction, with nanosmart water showing significant potential in improving recovery mechanisms. However, existing studies have struggled to achieve consistent and satisfactory results, particularly in leveraging the synergistic effects of silica nanoparticles (SNP) and surfactants. This study addresses this gap by exploring the role of amphoteric surfactants, whose unique behavior in nanosmart water systems remains insufficiently understood. A systematic investigation was conducted, focusing on SNP stability, interfacial tension (IFT), and wettability alteration, to evaluate the efficacy of this hybrid approach. The optimized formulation i.e., 100 ppm SNP in 2500 ppm KCl coupled with 0.2 wt% cocamidopropyl betaine (CAPB) demonstrated superior performance, reducing IFT almost 96 % and transforming the contact angle from 142° to 35°, achieving a strongly water-wet state. The study also reveals that pH plays a crucial role in surfactant performance, influencing electrostatic interactions and adsorption behaviour at the rock-fluid interface, with neutral pH (6–8) shows the optimum performance. These findings highlight the potential of nanosmart water-assisted amphoteric surfactants in enhancing oil displacement efficiency, reducing chemical losses, and improving reservoir adaptability, offering a promising approach for sustainable and cost-effective EOR applications.</div></div>","PeriodicalId":100578,"journal":{"name":"Geoenergy Science and Engineering","volume":"252 ","pages":"Article 213937"},"PeriodicalIF":0.0,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143911522","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}

{"title":"Nanosilica dispersion in water-based mud: Balancing sonication and mixing energy for optimized particle dynamics and fluid performance","authors":"Tawfik Elshehabi","doi":"10.1016/j.geoen.2025.213940","DOIUrl":"10.1016/j.geoen.2025.213940","url":null,"abstract":"<div><div>Sustainable drilling fluids are critical for subsurface energy and resources extraction. These drilling applications include oil and gas, geothermal energy, carbon storage, and rare earth in-situ mining. Environmental challenges and the high cost of oil-based muds demand sustainable, nanoparticle-enhanced water-based drilling fluids. However, the current API standards lack protocols for nanoparticle dispersion in drilling fluids. This study addresses this critical gap by systematically optimizing particle size distribution (PSD) through controlled sonication and high-shear mixing. Particle characterization and morphology were analyzed using dynamic light scattering, laser diffraction, dynamic image analysis, and scanning electron microscopy.</div><div>High-shear mixing improved the yield point of the base mud by 22 % with the Hamilton Beach Mixer (HBM) and 23 % with the Waring Blender (WB), while the 10-min gel strength increased by 19 % and 20 %, respectively. Filtrate loss over 30 min decreased by 16 % with the HBM and 25 % with the WB, driven by WB extensive particle size reduction of 52 % at high shear, compared to 39 % for the HBM. Results show that doubling the mixing speed halved the time required to reach similar particle sizes. Sonication reduced the hydrodynamic diameter of nanosilica clusters from an initial 960 nm at 2.5 min to 471 nm after 30 min, a 51 % reduction, compared to the manufacturer-reported dry individual particle size of 60–70 nm. The developed decay functions effectively modeled the effects of mixing and sonication on particle size reduction and helped optimize dispersion energy. Optimized nanosilica-enhanced mud, prepared with 2.5 min of sonication at 50 % amplitude and 30 min of high-shear mixing at 11,000 RPM using the WB, achieved a 48 % higher yield point (6.8–13.1 lb/100 ft²), 39 % improved filtration efficiency (20.2–14.5 mL), and 24 % thinner mud cake (1.36–1.8 mm) compared to under- or overmixed samples. Optimal performance was achieved at a 33 % nano-to-micro size ratio when nanosized barite particles were reduced by 53 % in size, and their specific surface area increased by 97 %, which bridged the shape and size gap between nanosilica agglomerates and bentonite sheets.</div><div>This study provides practical strategies for optimizing nanoparticle dispersion and refining energy-efficient drilling fluid mixing protocols. Improved particle dynamics bridged nanosilica and microsized additive gaps. These findings establish a foundation for next-generation fluids, drive advancements in API standards, and enhance field applications in geoenergy systems.</div></div>","PeriodicalId":100578,"journal":{"name":"Geoenergy Science and Engineering","volume":"252 ","pages":"Article 213940"},"PeriodicalIF":0.0,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143888093","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}

{"title":"Evaluating simple chromatographic formulae for Sor and EOR efficiency with a numerical SWCT model","authors":"Tom Pedersen","doi":"10.1016/j.geoen.2025.213936","DOIUrl":"10.1016/j.geoen.2025.213936","url":null,"abstract":"<div><div>Some of the residual oil after primary and secondary production can be extracted by enhanced oil recovery (EOR) methods. Before a full-scale EOR campaign is initiated, it is important to first perform an EOR pilot to estimate the residual oil saturation (Sor), before and after the EOR pilot. The reduction in S_or yields the expected efficiency of the full-scale EOR operation. A common method to estimate S_or is the Single Well Chemical Tracer (SWCT) test. Although there exist numerical models of SWCT tests, simple chromatographic formulae are still widely used to estimate S_or. Here, we study how well peak concentration time and mean residence time formulae perform in a chemical EOR injection scenario. Before the EOR injection S_or equals 22 % and afterwards 11 %, i.e., the real EOR efficiency is 22-11 = 11 %. Firstly, we generate synthetic tracer curves from an axial symmetric numerical SWCT model with parameters based on averages of input data from 39 published SWCT tests. The numerical model includes turbulent fluid flow and temperature in the wellbore, and fluid flow, temperature and chemical reactions in the oil-bearing formation. We use the initial reservoir temperature and the reservoir injection temperature from a simple analytical model in the formulae for the oil-water distribution constant of ethyl acetate to estimate S_or since these will be easily available for the interpreter. Using the peaks of the tracer concentration curves yields S_or estimates that are 0–4 % too low, whereas the mean residence time formula results in much larger errors of 4–12 %. The reduction in the pre-EOR S_or estimates due to pre-flushing is between 0 and 1 % and for the post-EOR S_or estimate between 2 and 3 %. The expected EOR efficiency, i.e., the difference between the pre- and post-EOR S_or values using tracer peaks is 10–11 % with the analytical temperature formula (10-12 % with the initial reservoir temperature). With the mean residence time formula, we obtain 4–6 % (5–6 % with the initial reservoir temperature). Since the true reduction in S_or is 11 %, we note that the peak time formula yields an excellent result, whereas the mean residence time formula yields poorer results. These results are when dissolution of calcite prevents pH to fall much below the region with lowest rates of hydrolysis of ethyl acetate. When there is only a low pH buffer capacity in the target formation, the difference between the tracer peaks and the mean residence time formulae is only about 1 %. The major limitation of the model is the assumption of axial symmetry. If complex geological settings, fractures and faults, horizontal wells etc. are to be investigated, a full 3D model is required.</div></div>","PeriodicalId":100578,"journal":{"name":"Geoenergy Science and Engineering","volume":"252 ","pages":"Article 213936"},"PeriodicalIF":0.0,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143894668","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}

{"title":"A full waveform inversion method for inverting S-wave velocity profiles of slow formations near borehole","authors":"Chao Zhang ,&nbsp;Hui Wang ,&nbsp;Da Chen ,&nbsp;Wei Guan ,&nbsp;Xiaodong He","doi":"10.1016/j.geoen.2025.213861","DOIUrl":"10.1016/j.geoen.2025.213861","url":null,"abstract":"<div><div>The borehole full waveform inversion (BFWI) method represents a novel approach for inverting S-wave velocities in slow formations by utilizing the comprehensive information available from acoustic logging waveforms. This method stands out from traditional techniques, which are limited to formations with uniform velocity within the axial resolution of the logging tool or where the radial distribution pattern of S-wave velocity is already known, and which only make use of a subset of the acoustic waveform data. The BFWI method iteratively enhances the model to align the inverted waveforms with the actual waveforms by leveraging the full waveform information, including both guided and critically refracted waves. This comprehensive use of data significantly improves the precision and reliability of estimating S-wave velocities in slow formations. The method’s effectiveness has been demonstrated through tests on thin-multilayer and alteration-zone models, showing that BFWI can accurately depict the S-wave velocity profiles in both wireline logging and logging-while-drilling scenarios. Moreover, within ultra-slow formations, BFWI not only accurately inverts the S-wave velocity profile but also retrieves the P-wave velocity with high precision, even in the presence of interfering leakage P-waves. This advancement offers a robust tool for the more precise measurement of S-wave velocity profiles in slow formations, potentially enhancing the accuracy of subsurface characterization in the petroleum industry.</div></div>","PeriodicalId":100578,"journal":{"name":"Geoenergy Science and Engineering","volume":"252 ","pages":"Article 213861"},"PeriodicalIF":0.0,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143873485","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}