Gas channeling during CO2 geological storage reduces sweep efficiency and increases leakage risk, while conventional anti-channeling agents suffer from limited stability and retention. In this study, a novel CO2-responsive in-situ mineralization plugging (RIMP) system, composed of aqueous ammonia (NH4OH) and calcium chloride (CaCl2), simultaneously achieves CO2 in-situ mineralization and mitigates channeling. The optimized RIMP formulation, determined through compatibility and mineralization capacity tests, demonstrated a CO2 mineralization capacity of 6.13 mg CO2/g RIMP with 1.6 wt% CaCl2 and 1.0 wt% NH4OH. Real-time monitoring of pH, mass change, Ca2+ concentration, and in-situ infrared spectra revealed a four-stage mineralization process governed by seven elementary reactions. XPS, XRD, SEM, and FTIR analyses showed that the mineralization product was composed of 84.4% calcite and 15.6% vaterite. Microscopic visualization and numerical simulations of in-situ CO2 mineralization in capillaries showed that CaCO3 particles form at the gas-liquid interface, diffuse into the liquid phase due to concentration gradients, and adhere to the capillary wall when the adsorption force dominates, resulting in localized accumulation. A reaction-diffusion model, established based on Fick's law and the Stokes-Einstein equation, showed that the distribution of mineralization products is mainly influenced by shut-in periods and pore size. Coreflooding tests demonstrated that the RIMP system increased plugging efficiency from 65.25% to 88.16% after 40 h of shut-in, and CO2 storage and mineralization efficiencies improved by 26.3% and 23.5%, respectively, consistent with the reaction-diffusion model predictions. The CO2-responsive insitu mineralization characteristic of RIMP offers a promising dual-function solution that mitigates gas channeling and enhances CO2 storage security through permanent mineral trapping.

Numerous magnesium-based curing materials with excellent pumping performance have been developed to address lost circulation during drilling and completion. However, the hydration mechanisms of these materials remain inadequately understood. This study introduced a MgO-based curing plugging material composed of curing agents, structural additives, activators (M), and retarders (HN). The materials were analyzed using SEM, XRD, EDS, and mechanical strength testing. The results indicate that the cured product transitions from Mg(OH)2 to a mixture of Mg(OH)2 and 5Mg(OH)2MgSO47H2O with the addition of structural additives and activators, significantly enhancing the strength of the materials. The retarder extended the initial setting time from 100 to 160 min, improving its practicality for lost circulation control in field applications. Furthermore, while adjusting the curing temperature and curing time had a minimal effect on the final product composition, these parameters promoted further crystal growth. The cured product primarily consisted of approximately 20% free water, 11% oxide, 13% hydroxide, and 52% original components. Based on the Krstulovic-Dabic theory, the hydration process could be divided into three stages: crystallization, nucleation, and crystal growth (NG), phase boundary reaction (I), and diffusion (D). These findings offered valuable insights into the hydration mechanisms of MgO-based curing plugging materials and their potential application in controlling lost circulation during drilling operations.

China's sea area contains tremendous reserves of natural gas hydrates.However,such hydrate reservoirs with shallow burial and low strength are often unconsolidated,and drilling-induced disturbance may cause wellbore collapse and impact both the efficiency and safety of drilling operations.In this paper,a multi-field coupling mathematical model based on the SH2 site of the Shenhu area of the South China Sea was developed to investigate the drilling disturbance to unconsolidated gas hydrate reservoirs.The applicability of the model was verified through the disturbance effect experiments of drilling fluids on hydrate-bearing sediments.Moreover,the variation of temperature,pore pressure,hydrate dissociation and wellbore instability in the near-wellbore region during drilling were analyzed.The results show that the disturbance by drilling fluid invasion on the temperature within the near-wellbore region is lower than that on pore pressure.The pore pressure of the model is completely affected after less than 6 hours of drilling,while only the formation temperature within 1.18 m around the wellbore is affected after 24 hours of drilling.Furthermore,although the ultimate dissociation range of natural gas hydrates reaches 0.408 m around the wellbore,the dissociation is rather intensive at the beginning of drilling and yet,gradually slows down with the proceeding of drilling.It is noted that the physical parameters of hydrate reservoirs within the near-wellbore region are mainly affected by hydrate dissociation and also change with the effective stress variation.Hydrate dissociation reduces the reservoir strength but significantly improves the reservoir porosity and permeability.Due to drilling disturbance,the near-wellbore plastic yield zone expands during drilling,with a declining expansion rate,and ultimately forms a yield ellipse around the wellbore,with its long axis parallel to the minimum horizontal principal stress,the ultimate borehole enlargement reaches 45.96%.The findings of this research provide theoretical support for the investigation of wellbore instability during the drilling of unconsolidated natural gas hydrate reservoirs.

Tailings pond detection and boundary extraction are important for the digital management and monitoring of tailings ponds. The tailings reservoir was further extracted accurately for the target area using the improved U-Net model,and the overall accuracy of the framework reached 98.12%. This method can extract various tailings ponds with high accuracy and speed from large area high spatial resolution remote sensing images,which effectively reduces the human and financial cost of tailings pond digital management and provides some reference for government departments to obtain tailings pond boundary information quickly.

In order to study the combustion-supporting mechanism and effect of combustion-supporting agents in fire flooding re-ignition of heavy oil reservoirs, further explore the types of combustion-supporting agents suitable for the fire flooding re-ignition of heavy oil reservoirs. The effects of paraffin oil and cetane on the combustion-supporting effect of heavy oil reservoir in fire flooding re-ignition were studied by adding different organic solvents into heavy oil sands for the first time. The research results show that the paraffin oil can significantly increase the heat release in the low temperature stage, which is more conducive to the oil sand for the high temperature oxidation reaction, so that the heavy oil sand can be ignited under the low temperature conditions, the combustion effect is good, and the displacement effect is obvious. The research clarifies the combustion-supporting mechanism and effect of combustion-supporting agents in fire flooding re-ignition of heavy oil reservoirs, which lays a theoretical foundation for the subsequent exploration of other combustion-supporting agents and has important significance for guiding the development of heavy oil reservoirs by fire flooding.

集成学习在处理小样本问题上具有相当的优势,相较于其他集成模式,Stacking模式对集成单元的类型并没有限制,所以具有相当的研究潜力.在油气领域,如何对实验室条件下对金属腐蚀数据的充分利用,是当前急需解决的问题.为了探究stacking算法在小样本预测上的适用性,本研究以实验室条件下获得的99组金属腐蚀数据为基础,在预处理后,然后选择了 11组基础集成模型以stacking的模式进行集成并预测.最终的结果表明stacking模式并不适用于该数据集下的小样本预测.

Nano-material enhanced viscoelastic surfactant (VES) systems have attracted considerable attention as clean fracturing fluids due to their improved rheological properties compared to conventional VES systems. In this study, a pseudo-interpenetrating network VES (PINVES) fracturing fluid, which was composed of sodium oleate (NaOA), potassium chloride (KCl) and surface-modified cellulose nanofibril (SMCNF), was proposed. The rheological behavior of the PINVES fracturing fluid and the interaction mechanism between SMCNF and wormlike micelles (WLMs) were comprehensively studied. The zero-shear viscosity of PINVES increased with appropriate SMCNF addition but decreased with excess SMCNF addition. Meanwhile, the typical viscosity-flat of WLMs gradually disappeared when the concentration of SMCNF exceeded the optimum value. The optimum value was closely related to the functional groups on the surface of SMCNF. The SMCNF physically crosslinked the WLMs through hydrogen bonding but the sulfonic groups and hydrophobic groups on the surface of SMCNF destroyed the network of WLMs at relatively high SMCNF concentration. The network formed by SMCNF dominated the rheological behavior of the PINVES fracturing fluid simultaneously. In addition, due to the competition between the network of WLMs and the network of SMCNF, the PINVES fracturing fluid exhibited higher concentration dependence of surfactant in rheological behavior than conventional VES fracturing fluid. The SMCNF network also endowed the PINVES with better temperature-resistance. Furthermore, the relaxation time and elasticity of PINVES fracturing fluid increased with the increase in SMCNF concentration. The static proppant settling tests demonstrated that the addition of SMCNF improved the sand-carrying capability of PINVES fracturing fluid. The results of the study could provide some enlightenments on the application of SMCNFs in reservoir stimulation.

针对当前含多种电气故障的复杂电路电弧故障识别率低、训练速度慢的问题,提出一种窗口划分结合小波分解与经验模态分解(empirical mode decomposition,EMD)分别从时域、频域及时间尺度等多个维度提取电流特征量,利用机器学习分类模型进行电弧故障识别的方法.首先,利用搭建的电气故障实验平台采集故障及正常电流数据,并将电流数据进行窗口分段,然后分别使用小波变换与EMD方法对电流信号进行分解并计算不同维度上的特征量,将该特征信息作为分类算法的输入进行电弧故障诊断.经实验验证,该特征提取方法在梯度提升决策树(gradient boosting decision tree,GBDT)上的电弧故障检测准确率高达98％,相比电流不分段的方式分类准确率提升了1.87％,能有效获取电弧故障特征,实现对电弧故障高效率与高准确率检测.

近年来随着人工智能的迅速发展,基于计算机视觉的图像识别在各个领域一度成为研究热点.本文首先对机器学习和深度学习的基础概念和结构进行概述,在此基础上,探索图像识别技术与地质勘探领域的学科交叉研究情况,并分别阐述机器学习和深度学习上地质领域的岩石图像识别研究特征和区别.最后基于上述分析,对人工智能在岩石图像上的应用前景进行讨论,认为基于深度学习的计算机视觉技术在地质领域岩石图像上的研究对于传统地质及相关行业的发展具有重要意义.

文章基于PSR-NES模型构建区域土地生态状况评估指标体系,利用排序法和层次分析法原理确定指标权重,采用综合指数法进行加权叠加得到土地生态综合指数(LEI),并通过重分类对研究区的土地生态状况进行等级划分,进而通过障碍度判别主要影响因素.结果 表明,2010年和2016年LEI分别介于0.22 ～0.68和0.26 ～0.68,LEI的平均值增加了0.01;土地生态状况较好的Ⅰ等区、Ⅱ等区主要集中在研究区西北部山区和东南平原区,Ⅲ等区、Ⅳ等区和Ⅴ等区主要集中在大邑县西部极高山区、丘陵区和城镇建设区;较2010年Ⅰ等区和Ⅱ等区面积增加,Ⅲ等区、Ⅳ等区和Ⅴ等区面积减少.植被覆盖状况、水资源分布情况、地形因素、地质灾害危害程度和气象灾害等对研究区土地生态状况影响较显著;该地在灾后重建和震后恢复中的响应比较积极,高标准农田建设、永久基本农田保护区划定和生态红线划定工作的开展对改善区域土地生态状况具有积极作用.

This proof-of-concept study demonstrates a promising approach to enhance the CO2 capture capacity of liquid amines, in which the amines were infused into microgel particles. A diverse range of amine infused microgels (AIMGs) were readily prepared within 5 min by adding microgel particles into different amine solutions. The AIMGs absorb CO2 based on the infused amines. Due to the solid particle structure, the space among the AIMG particles provided diffusion channels for the CO2 molecule and enhanced the contact efficiency of the amines and CO2. As a result, the absorption efficiency of the amines was significantly increased resulting in higher CO2 uptake and faster absorption kinetics for the AIMGs compared to the conventional bulk amine solutions. Furthermore, by 'locking' the amine solutions in the microgel particles, the corrosion and foaming issues of amine solutions could be substantially mitigated. Therefore, the amine solutions which have higher concentrations than the commercial counterparts could be used in the preparation of AIMGs. Due to the thermally stable network structure, the AIMGs which were prepared by the amines with low volatility exhibited favorable cyclic capacity during the temperature-swing regeneration process.

In order to solve the problem of excess production of carbon monoxide in cyclic steam stimulation process of Hongshan oilfield, the corresponding laboratory researches have been carried out. Through physical simulation experiments and multi-parameter sensitivity analysis, the effect of technological parameters such as steam temperature, steam injection volume, and soaking time on carbon monoxide output concentration have been investigated. Furthermore, the possible solutions for carbon monoxide production have been proposed based on the effects of different factors. The results show that the influencing order of the three dominant factors is steam temperature, steam injection volume and soaking time. Reducing the steam temperature can effectively reduce the carbon monoxide output concentration, but when the steam temperature drops below 220 ℃, the crude oil production will be adversely affected. Therefore, for the wells in Hongshan oilfield with relative low carbon monoxide exceeding degree, it is recommended to reduce the steam temperature to 220 ℃ to keep the carbon monoxide concentrations below safe levels; for those ones with relative high exceeding degree, in addition to the above measures, the steam injection volume should be increased to ensure that the periodic oil production does not decrease significantly.

针对如何在水驱后进一步开发高含水高温油藏,提出了一种表面活性剂就地乳化驱油技术,对油包水(W/O)型乳化剂OB-2体系进行了乳化特性评价及乳状液驱油研究.研究结果表明,随着乳化剂浓度增大,乳液黏度先增大后减小;对于X油藏原油,乳化剂最佳浓度为0.3wt％,在此浓度下,油水界面张力可降低至10-2 mN/m数量级;在水油体积比低于7:3时,乳化剂OB-2可促使油水两相完全乳化,形成高黏度的W/O型乳液,其中,水油体积比为7:3时乳液黏度最大,增黏率高达370％.岩心驱油实验结果表明,均质条件下,水驱后注入0.3PV乳化剂OB-2体系,可提高原油采收率达26.15％;非均质条件下,该乳化体系可在级差低于7.6时表现出良好的流度控制及非均质调控能力,扩大波及体积.

The morphology and rheological properties of polymer microspheres PM1 were evaluated by optical microscope and rheometer. The effects of injection rate and concentration of microsphere system on the migration and plugging properties in porous media as well as the profile control ability of polymer microspheres to heterogeneous formation were investigated respectively by single core and parallel cores flooding experiments. The results showed that the microspheres had a high degree of sphericity with micro scale and its apparent viscosity was close to water at a relative high shear rate. The plugging ability of microspheres to pore throats increased with the decrease of seepage velocity or the increase of mass concentration. The microspheres had strong profile control ability to heterogeneous formation. If the measures that relative water absorption of low permeable core after profile control and oil displacement was greater than or equal to 35 % could be deemed to be appropriate, the upper limit of the permeability contrast, corresponding to which the microspheres could effectively improve the reservoir heterogeneity, would be about 20. For some strongly heterogeneous reservoirs existing fractures or large pores, the combined technique of profile control and flooding about alternating slugs of large-scale and micro-scale microspheres could be considered preferentially.

青藏高原拉萨地体中西部广泛发育白垩纪岩浆岩,为探讨青藏高原新生代之前的地质演化历史提供了重要线索.然而其成因及构造背景还存在不同的认识,严重阻碍了青藏高原演化历程的反演工作.本文对藏西措勤县尼雄地区的一套花岗闪长岩进行了详细的年代学和全岩地球化学分析,结果表明,尼雄花岗闪长岩的SiO 2含量为65.24％ ～67.61％,Na 2 O/K2 O为0.91～3.93,铝饱和指数(A/CNK)为0.94～1.14,属I型钙碱性岩石.它们富集轻稀土元素(LREEs)和大离子亲石元素(LILEs,如Rb、Th等),亏损重稀土元素(HREEs)和高场强元素(HFSEs,如Nb、Ta等),轻重稀土分馏明显[(La/Yb)N=7.6～12.2],具有弱-中等的负Eu异常(δEu为0.6～0.9).两个花岗闪长岩样品中获得的岩浆锆石U-Pb定年结果分别为119.7 Ma和120.5 Ma,代表了尼雄地区的花岗闪长岩为早白垩世晚期岩浆活动的产物.综合研究表明,这套花岗闪长岩主要来源于古老下地壳物质的重熔,并伴有同期幔源岩浆的加入和混合.它们可能是雅鲁藏布江新特提斯洋壳岩石圈北向俯冲的产物.

地质灾害是影响长输管线安全运行的重要因素,为减少地质灾害对长输管线的影响,有效预防、规避长输管线的安全风险,本文基于西南油气田仁寿作业区的地质灾害数据,以研究区地质灾害为预测变量,高程、坡度、坡向、地表覆盖为响应变量,采用人工神经网络、决策树、支持向量机3种机器学习方法分析研究区域地质灾害的发生规律,并进一步预测研究区内长输管线发生地质灾害的概率.通过模型对比,相较于人工神经网络和支持向量机,决策树的方法具有更高的预测精度,其预测正确率达0.86.本文的分析结果对研究区管线管理部门具有重要参考价值,相关部门可根据模型预测出的管线点发生地质灾害的概率,提前做好地质灾害预防工作.

改革开放以来我国经济得到飞速发展,油气需求量不断攀升,国内产能无法满足消费需求.截至2018年,我国石油对外依存度已逼近70％,天然气对外依存度超过40％,超过美国成为世界第一大石油进口国.随着“一带一路”战略推进,我国石油企业要实现与富油国经贸合作,势必与跨国石油公司展开竞争,没有强大的技术实力是难以取胜的.石油属于技术和资金密集型行业,技术进步和创新对减少油气勘探开发与生产建设成本、安全成本、环境成本,以及提升开采效率和油品质量都是至关重要的.

晚古生代是拉萨地块地质演化的重要转折期,一些关键地质问题存在争论,如拉萨地块来源问题.选择西藏措勤地区上石炭统永珠组为研究对象,石英砂岩中碎屑锆石U-Pb测年数据显示523Ma、920Ma两个年龄峰值.通过与拉萨地块及其周缘晚石炭世冰期之前地层碎屑锆石对比,认为拉萨地块永珠组920Ma年龄峰值更具有冈瓦纳大陆靠印度一侧的物源特征,其与南羌塘、拉萨、喜马拉雅微陆块在裂离之前具有显著的亲缘关系.而含有冰筏碎屑的拉嘎组和来姑组中包含的西澳大利亚物源信息(约1180Ma年龄峰值),暗示来自西澳大利亚的冰筏可能通过洋流作用漂移至拉萨地块而后沉积冰筏碎屑.

Nano-ZrO2 was synthesized by oil-water interface method as crosslinking agent. The synthesized nano-ZrO2 was characterized by SEM,FTIR and UV-Vis diffuse reflectance spectra. The effects of temperature,time and other factors on the synthesis of nano-t-ZrO2 were investigated by single factor experiments. The synthesized nano-ZrO2 was prepared into 1.5%(w) dispersion solution. The cross-linking gel was formed by crosslinking 0.6%(w) hydroxypropyl guanidine gum with volume ratio 1.5%(φ). The cross-linking gel was characterized and its properties were tested. The experimental results show that the optimum preparation conditions of nano-t-ZrO2 are 100 ℃,24 h,sodium lauryl sulfate is a surfactant,cyclohexane is an oil phase,and the mineralizer is a 4 mol/L NaOH solution;nano-zirconia is tetragonal zirconia with a large amount of hydroxyl groups on its surface;the cross-linked gel formed has good pick-up and temperature resistance,and shearing 120 min at 100 ℃,170 s-1, the viscosity of gel fracturing fluid system remains about 100 mPa·s,and the breakability,residue content and suspended sand properties all meet the working requirements.

Firstly, we evaluated the polymer microspheres and polymer properties, then, studied the migration and plugging properties of the microspheres, polymer and compound system（microspheres + polymer） by microporous membrane filtration device, and implemented the profile control and oil displacement experiments about the systems above by the parallel cores physical simulation displacement apparatus. The results indicated that the polymer microspheres was spherical micron-grade particles with superior dispersibility, and its apparent viscosity, which was much less than that of polymer with the same mass concentration, is close to that of water under the relatively high shear rate. The polymer failed to plug the micropores effectively. The plugging ability of the microspheres was the strongest, followed by the compound system. Under the condition of the strong heterogeneity, the effects of the profile control and the oil displacement of the compound system attained the best and corresponding enhanced oil recovery for high and low permeable cores were respectively 20.86 % and 36.89 %. There was a synergistic effect between the microspheres and polymer for the compound system. That the amount of the microspheres captured and migration property reduced and intensified in the porous medium mainly due to the impact of carrying and lubrication of polymer. Additionally, the influence of mobility ratio control and viscoelastic oil displacement of polymer could effectively improve oil recovery. For the actual reservoirs with relatively strong heterogeneous conditions, it was essential to take the profile control and flooding technology of the microspheres/polymer compound system into account firstly.