Research on thermal insulation materials properties under HTHP conditions for deep oil and gas reservoir rock ITP-Coring

Deep oil and gas reservoirs are under high-temperature conditions,but traditional coring methods do not consider temperature-preserved measures and ignore the influence of temperature on rock porosity and permeability,resulting in distorted resource assessments.The development of in situ temperaturepreserved coring(ITP-Coring)technology for deep reservoir rock is urgent,and thermal insulation materials are key.Therefore,hollow glass microsphere/epoxy resin thermal insulation materials(HGM/EP materials)were proposed as thermal insulation materials.The materials properties under coupled hightemperature and high-pressure(HTHP)conditions were tested.The results indicated that high pressures led to HGM destruction and that the materials water absorption significantly increased;additionally,increasing temperature accelerated the process.High temperatures directly caused the thermal conductivity of the materials to increase;additionally,the thermal conduction and convection of water caused by high pressures led to an exponential increase in the thermal conductivity.High temperatures weakened the matrix,and high pressures destroyed the HGM,which resulted in a decrease in the tensile mechanical properties of the materials.The materials entered the high elastic state at 150℃,and the mechanical properties were weakened more obviously,while the pressure led to a significant effect when the water absorption was above 10%.Meanwhile,the tensile strength/strain were 13.62 MPa/1.3%and 6.09 MPa/0.86%at 100℃ and 100 MPa,respectively,which meet the application requirements of the self-designed coring device.Finally,K46-f40 and K46-f50 HGM/EP materials were proven to be suitable for ITP-Coring under coupled conditions below 100℃ and 100 MPa.To further improve the materials properties,the interface layer and EP matrix should be optimized.The results can provide references for the optimization and engineering application of materials and thus technical support for deep oil and gas resource development.

Characteristics and Trends of Deep Oil and Gas Research in China (1984-2024)—Research from the Perspective of CiteSpace

Deep oil and gas refer to oil and gas resources buried at a significant depth below the surface. Compared with conventional oil and gas, deep oil and gas often face more complex geological conditions and technological challenges, therefore, the development and exploitation of these oil and gas resources require advanced technology and equipment. Use bibliometrics to study academic literature. Select available data and download it in “RefWorks” format. Import the data into Cite Space 6.3.R2 software for author collaboration and keyword emergence analysis and visualization. Use Microsoft Excel 2016 software to analyze the annual publication volume, literature institutions, and disciplinary distribution of domestic and international scholarly literature. Research has found that: 1) The institution with the highest number of publications in the field of deep oil and gas in China is the China Petroleum Exploration and Development Research Institute;The author with the highest number of publications is Zhu Guangyou;The author with the highest citation frequency is Jia Chengzao;The research work in the field of deep oil and gas in China is mainly led by national level fund projects. 2) The research hot-spots of deep oil and gas in China are showing a trend of shifting from Jilin and Henan to Xinjiang and Sichuan. 3) The research on deep oil and gas fields in the Paleogene of China is mainly concentrated in Henan Province and Shandong Province. The Lower Tertiary, Cambrian and Jurassic are respectively concentrated in Dongpu Sag, Dongying Sag, Sichuan Basin, Tarim Basin in Xinjiang, the Junggar Basin and Qaidam Basin in Qinghai. The Sinian, Ordovician, Cretaceous, and Neogene systems are mainly concentrated in Sichuan, Xinjiang, and Qinghai provinces. The Permian system is mainly located in the southwest and Northwest of China. This article uses a new research perspective and methodology to systematically analyze the current situation and future development trends of deep oil and gas exploration and development in China, which is of great significance for promoting effective exploration and development of deep oil and gas resources.

Pressure control method and device innovative design for deep oil in-situ exploration and coring

Deep oil exploration coring technology cannot accurately maintain the in-situ pressure and temperature of samples, which leads to a distortion of deep oil and gas resource reserve evaluations based on conventional cores and cannot guide the development of deep oil and gas resources on Earth. The fundamental reason is the lack of temperature and pressure control in in-situ coring environments. In this paper, a pressure control method of a coring device is studied. The theory and method of deep intelligent temperature-pressure coupling control are innovatively proposed, and a multifield coupling dynamic sealing model is established. The optimal cardinality three term PID (Proportional-Integral-Differential) intelligent control algorithm of pressure system is developed. The temperature-pressure characteristic of the gas-liquid two-phase cavity is analyzed, and the pressure intelligent control is carried out based on three term PID control algorithms. An in-situ condition-preserved coring (ICP-Coring) device is developed, and an intelligent control system for the temperature and pressure of the coring device is designed and verified by experiments. The results show that the temperature-pressure coupling control system can effectively realize stable sealing under temperature-pressure fields of 140 MPa and 150 °C. The temperature-pressure coupling control method can accurately realize a constant pressure inside the coring device. The maximum working pressure is 140 MPa, and the effective pressure compensation range is 20 MPa. The numerical simulation experiment of pressure system control algorithm is carried out, and the optimal cardinality and three term coefficients are obtained. The pressure steady-state error is less than 0.01%. The method of temperature-pressure coupling control has guiding significance for coring device research, and is also the basis for temperature-pressure decoupling control in ICP-Coring.

Enrichment Mechanism and Prospects of Deep Oil and Gas

With the deepening of oil and gas exploration,the importance of depth is increasingly highlighted.The risk of preservation of storage space in deep reservoirs is greater than that in shallow and medium layers.Deep layers mean older strata,more complex structural evolution and more complex hydrocarbon accumulation processes,and even adjustment and transformation of oil and gas reservoirs.This paper systematically investigates the current status and research progress of deep oil and gas exploration around the world and looks forward to the future research focus of deep oil and gas.In the deep,especially the ultra-deep layers,carbonate reservoirs play a more important role than clastic rocks.Karst,fault-karst and dolomite reservoirs are the main types of deep and ultra-deep reservoirs.The common feature of most deep large and medium-sized oil and gas reservoirs is that they formed in the early with shallow depth.Fault activity and evolution of trap highs are the main ways to cause physical adjustment of oil and gas reservoirs.Crude oil cracking and thermochemical sulfate reduction(TSR)are the main chemical modification effects in the reservoir.Large-scale high-quality dolomite reservoirs is the main direction of deep oil and gas exploration.Accurate identification of oil and gas charging,adjustment and reformation processes is the key to understanding deep oil and gas distribution.High-precision detection technology and high-precision dating technology are an important guarantee for deep oil and gas research.

Theoretical Progress and Key Technologies of Onshore Ultra-Deep Oil/Gas Exploration

Oil/gas exploration around the world has extended into deep and ultra-deep strata because it is increasingly difficult to find new large-scale oil/gas reservoirs in shallow–middle buried strata. In recent years, China has made remarkable achievements in oil/gas exploration in ultra-deep areas including carbonate and clastic reservoirs. Some (ultra) large-scale oil and gas fields have been discovered. The oil/gas accumulation mechanisms and key technologies of oil/gas reservoir exploration and development are summarized in this study in order to share China’s experiences. Ultra-deep oil/gas originates from numerous sources of hydrocarbons and multiphase charging. Liquid hydrocarbons can form in ultradeep layers due to low geothermal gradients or overpressures, and the natural gas composition in ultra-deep areas is complicated by the reactions between deep hydrocarbons, water, and rock or by the addition of mantle- or crust-sourced gases. These oils/gases are mainly stored in the original highenergy reef/shoal complexes or in sand body sediments. They usually have high original porosity. Secondary pores are often developed by dissolution, dolomitization, and fracturing in the late stage. The early pores have been preserved by retentive diageneses such as the early charging of hydrocarbons. Oil/gas accumulation in ultra-deep areas generally has the characteristics of near-source accumulation and sustained preservation. The effective exploration and development of ultra-deep oil/gas reservoirs depend on the support of key technologies. Use of the latest technologies such as seismic signal acquisition and processing, low porosity and permeability zone prediction, and gas–water identification has enabled the discovery of ultra-deep oil/gas resources. In addition, advanced technologies for drilling, completion, and oil/gas testing have ensured the effective development of these fields.

DeeplabV3+中引入注意力机制的小面积溢油识别方法

海面溢油危害大、分布广、时间空间不确定性大,对海洋溢油进行高精度识别与监测对全球生态环境的保护有着重要意义。针对传统卷积神经网络模型对小面积溢油分类不准确的问题,提出一种基于深度学习的SAR影像海上小面积溢油的高精度提取方法。该方法以DeeplabV3+网络模型为基础,引入SE注意力机制来提高网络对海面上小面积溢油的分类精度。基于欧空局开源数据集Oil Spill Detection Dataset建立了海面溢油提取模型,训练得到的平均交并比为77.70%,平均像素精度为98.16%。通过目视对比模型预测图和对比两类精度指标,发现经过注意力机制优化后的DeeplabV3+网络模型明显优于原始网络模型,对小面积溢油监测的效果明显提升。

Driving forces and their relative contributions to hydrocarbon expulsion from deep source rocks: A case of the Cambrian source rocks in the Tarim Basin

To thoroughly understand the dynamic mechanism of hydrocarbon expulsion from deep source rocks,in this study,five types of hydrocarbon expulsion dynamics(thermal expansion,hydrocarbon diffusion,compaction,product volume expansion,and capillary pressure difference(CPD))are studied.A model is proposed herein to evaluate the relative contribution of different dynamics for hydrocarbon expulsion using the principle of mass balance,and the model has been applied to the Cambrian source rocks in the Tarim Basin.The evaluation results show that during hydrocarbon expulsion from the source rocks,the relative contribution of CPD is the largest(>50%),followed by compaction(10%-40%),product volume expansion(5%-30%),and thermal expansion(2%-20%).The relative contribution of diffusion to hydrocarbon expulsion is minimal(<10%).These results demonstrate that CPD plays an important role in the hydrocarbon expulsion process of deep source rocks.The hydrocarbon expulsion process of source rocks can be categorized into three stages based on the contribution of different dynamics to the process:the first stage is dominated by compaction and diffusion to expel hydrocarbons,the second stage is dominated by product volume expansion and CPD,and the third stage is dominated by product volume expansion and CPD.This research offers new insights into hydrocarbon exploration in tight oil and gas reservoirs.

Prediction of wax precipitation region in wellbore during deep water oil well testing

During deep water oil well testing, the low temperature environment is easy to cause wax precipitation, which affects the normal operation of the test and increases operating costs and risks. Therefore, a numerical method for predicting the wax precipitation region in oil strings was proposed based on the temperature and pressure fields of deep water test string and the wax precipitation calculation model. And the factors affecting the wax precipitation region were analyzed. The results show that: the wax precipitation region decreases with the increase of production rate, and increases with the decrease of geothermal gradient, increase of water depth and drop of water-cut of produced fluid, and increases slightly with the increase of formation pressure. Due to the effect of temperature and pressure fields, wax precipitation region is large in test strings at the beginning of well production. Wax precipitation region gradually increases with the increase of shut-in time. These conclusions can guide wax prevention during the testing of deep water oil well, to ensure the success of the test.

Origin and accumulation of high-maturity oil and gas in deep parts of the Baxian Depression, Bohai Bay Basin, China

Great quantities of light oil and gas are produced from deep buried hill reservoirs at depths of 5,641 m to 6,027 m and 190 ℃ to 201 ℃ in the Niudong-1 Well, representing the deepest and hottest commercial hydrocarbons discovered in the Bohai Bay Basin in eastern China. This discovery suggests favorable exploration prospects for the deep parts of the basin. However, the discovery raises questions regarding the genesis and accumulation of hydrocarbons in deep reservoirs. Based on the geochemical features of the hydrocarbons and characteristics of the source rocks as well as thermal simulation experiments of hydrocarbon generation, we conclude that the oil and gas were generated from the highly mature Sha-4 Member （Es4） source rocks instead of thermal cracking of crude oils in earlier accumulations. The source kitchen with abnormal pressures and karsted carbonate reservoirs control the formation of high-maturity hydrocarbon accumulations in the buried hills （i.e., Niudong-1） in conjunction with several structural-lithologic traps in the ES4 reservoirs since the deposition of the upper Minghuazhen Formation. This means the oil and gas exploration potential in the deep parts of the Baxian Depression is probably high.

稠油化学复合冷采技术研究与应用

我国稠油储量可观,其中60%的是深层稠油,而主流的蒸汽吞吐等热采技术采收率不足20%;稠油资源开发潜力极大,积极探索新的开采方式以提高采收率是石油领域高质量发展的必然选择。本文着重阐述稠油化学复合冷采技术体系构建及其现场应用,为中深层稠油的新型绿色低成本接替技术发展提供有效方案。在分析稠油组分的基础上,细致剖析稠油结构致黏机理,包括化学降黏机理、降低启动压力梯度机理、提高驱油效果机理在内的提高采收率机理,以丰富理论认识。面向工程应用亟需,从水溶性降黏剂分子设计与合成、自组装调堵剂研发两方面出发,突破稠油绿色化学驱油体系。基于发展的稠油化学复合冷采技术,完成了3个稠油油田示范工程应用,在提高产油量、控制含水率方面取得了良好成效。进一步梳理了分子采油理论与技术、渗流理论与数值模拟技术等方面的后续发展要点,以为深层稠油的绿色高效开发接替技术研究、稠油化学复合冷采技术推广应用研究等提供启发和参考。

中深层稠油水平井前置CO_(2)蓄能压裂技术

利用准噶尔盆地西北缘乌夏地区中深层稠油油藏参数,对水平井前置CO_(2)蓄能压裂技术的开发机理、关键操作参数及开发效果进行了详细研究。研究结果表明:①伴随压裂—焖井—生产等开发阶段的延伸,前置CO_(2)蓄能压裂后的油井逐步显现出增能改造、扩散降黏、膨胀补能、释压成泡沫油流等特性,井底流压提高了2~4MPa,CO_(2)扩散至油藏的1/3,原油黏度降至500mPa·s以下,泡沫油流明显;②研究区最优压裂段间距为60m、裂缝半长为90m、裂缝导流能力为10t/m,CO_(2)最佳注入强度为1.5m3/m,注入速度为1.8m3/min,油井焖井时间为30d,油藏采收率提高了2%~3%;③通过与常规压裂生产效果进行对比,前置CO_(2)蓄能压裂技术可使产油量提高5.2t/d,预测CO_(2)换油率达2.45,开发效果显著提升。

增效型无土相仿生油基钻井液技术的研究与应用

针对深井超深井钻井过程中钻遇高温高压、井壁失稳及井下复杂情况的难题,基于仿生学、超分子化学以及岩石表面润湿性理论,通过优选仿生增效剂、仿生提切剂及仿生降滤失剂,配套相关处理剂,最终形成了一套适用于深井、超深井地层钻探的增效型无土相仿生油基钻井液体系。研究发现,建立的增效型无土相仿生油基钻井液体系可抗220℃高温,配制密度为2.4 g/cm^(3),破乳电压大于400 V,高温高压滤失量为3.2 mL,人造岩心在该体系中220℃下老化后的抗压强度达到7.1 MPa,平均渗透率恢复值为93.9%。现场应用情况表明,体系流变性能稳定,平均机械钻速比邻井提高16%,平均井径扩大率仅为1.25%,可有效解决深井超深井钻井过程中出现的井壁失稳难题,为我国深井超深井的钻探提供了技术保障。

深层、超深层定向钻井中若干基础研究进展与展望

深层、超深层定向钻井具有“垂深大与水平延伸远”的双重特征,受到复杂地层、高温高压、超长裸眼等多重因素约束,其安全高效作业面临着更大的全方位技术挑战。为此,着眼于深层、超深层定向钻井的提速提效问题,系统总结了定向钻井的发展概况与技术特点,选取了深层、超深层定向钻井中力学方面的几个重要基础问题,分析了国内外专家学者的相关研究进展和最新研究成果,最后展望了深层、超深层定向钻井基础理论研究发展趋势并提出相关建议。研究结果表明:①大小偏差融合控制算法兼顾了井眼轨迹的控制精度、光滑度等多目标约束,适应于深层、超深层条件下井眼轨迹实时控制要求;②合理优化振动减阻工具个数、安放位置及其激励力幅值,可显著降低井下管柱摩阻,并有效提高机械钻速;③基于误差补偿机制的机械钻速融合预测模型既保留了机理模型的可解释性,又具有较高的预测精度;④套管复合磨损预测模型突破了经典“单月牙”模式的局限性,实现了复合模式下套管磨损形状与深度的同步预测。结论认为,深层、超深层定向井和水平井是未来油气井工程的重要发展方向之一,需要加强多因素耦合机理、钻井延伸极限、机理与数据融合驱动等方面的基础研究,以推动复杂油气井工程基础理论的创新与发展,为深层、超深层钻井工程技术进步提供必要的基础理论支撑。

THE RELATIONS BETWEEN DEEP DYNAMIC PROCESS AND THE FORMATION OF OIL-GAS POOLS IN THE SONGLIAO BASIN,CHINA

THE RELATIONS BETWEEN DEEPDYNAMIC PROCESS AND THEFORMATION OF OIL-GAS POOLS INTHE SONGLIAO BASIN, CHINALi Zhi’an(Changsha Institute of Geotectonics, Academia Sinica, Changsha, 410013, Hunan, China)Songliao basin, crust structure, deep dynamics, the formation of oil-gas poolsThis essay deals in detail with the inhomogeneity of the crust structure and the variation of the Moho, the process of deep dynamics and also relations of deep dynamic process to the formation of oil-gas pools in Songliao Basin.

库车前陆冲断带构造分层变形特征

库车前陆冲断带地震资料信噪比低,具有多解性。利用高分辨率三维地震、钻井、油气分析化验等资料,对库车前陆冲断带地层组合进行系统描述,精细解释构造模型,深入剖析油气成藏体系,认为库车前陆冲断带发育古近系和新近系膏盐岩层及三叠系和侏罗系煤层2套滑脱层,具有分层滑脱、垂向叠置、多期变形的特征,浅层构造发育盖层滑脱褶皱,深层发育基底卷入式叠瓦状逆冲构造,膏盐岩层和煤层发生滑脱塑性变形,发育加里东运动期、海西运动晚期—印支运动期和燕山运动期—喜马拉雅运动期3期断裂,海西运动晚期—印支运动期构造控制中生界沉积,由北向南具有超覆减薄的特征。库车前陆冲断带分层构造变形控制油气分层运聚,煤层以上的油气主要来自侏罗系烃源岩,煤层之下的油气主要来自三叠系,三叠系烃源岩生烃量占60%,大量油气仍保存在煤层之下。

变压器油在线检测与故障预警系统实验装置设计

电力变压器在电网中担任着核心角色,但是目前的维修模式存在着盲目强制性,往往消耗大量人力物力,为解决此现象,通过研发变压器油在线检测与故障预警系统实验装置,建立应修尽修的预测性维修模式,实现变压器在线运行状态实时监测,运行故障分析预警功能。通过FreeRTOS并行实时采集数据变压器油的基础数据,利用python的pytorch深度学习模型处理数据,实现通过变压器油间接监测变压器的运行状态,上报实时数据与预警信息,减少由于故障引发事故发生的概率,节省变压器检修的人力物力消耗,加快我国智慧电网的建设过程。

塔里木盆地海相原油热裂解的阶段性特征及其意义

塔里木盆地台盆区深层油气勘探不断取得突破,原油热稳定性及其裂解特征已成为制约塔里木盆地深层下一步油气勘探与评价的瓶颈之一。本研究选择塔河地区未遭受明显次生改造原油,采用黄金管封闭体系热压模拟实验,在恒压、程序升温条件下,系统分析不同热演化阶段原油热裂解产物与残余物的分子组成。结果表明,随着热演化程度的增加,伴随着原油热裂解程度增加引起的化合物裂解、环化、芳构化作用,气体和液态烃产率呈现显著的阶段性变化,并显示不同的分子地球化学特征,据此分为3个阶段:①初始裂解期(Easy Ro<1.2%),与原始油样比较,残留产物全烃色谱特征未发生显著变化;②主裂解期(1.2%<Easy Ro<3.8%),又以Easy Ro=2.0%为界分为快速裂解阶段和缓慢裂解阶段,残留产物中正构烷烃含量逐渐降低,同时伴随低环数芳烃化合物含量的逐渐增加,而稠环芳烃含量的逐渐增加则与低环数芳烃含量逐渐减少相对应;③裂解末期(3.8%<Easy Ro<4.5%),以高含量稠环芳烃的富集为标志,其中残留物全烃色谱上以四环芳烃占绝对优势。研究结果对有效描述原油的热演化过程、明确原油不同热裂解阶段油气产物的组成和产率特征以及深层原油热稳定性评价具有重要指导意义。

准噶尔盆地深层油气勘探地震采集关键技术及效果

准噶尔盆地目前4 500 m以深的深层油气探明率较低,近年来深层油气勘探目标成为该地区勘探发现的战略接替区。为了查清地下深层结构,重新构建和部署了准噶尔盆地二维地震格架线,利用以往采集资料和重新采集的新资料拼接形成了数十条线组成的二维格架网。基于“两宽一高”技术体系,采用一系列采集关键技术,如“高激发密度、高接收密度、高覆盖密度和长排列”的“三高一长”采集技术,解决了准噶尔盆地深层油气勘探地震采集面临的深层目标地震信号“能量低、干扰强、成像差和不成像”等难题。新采集并经后期处理后的资料成像效果显著提高,为建立盆地石炭系-二叠系统一的地层格架、明确石炭系隆凹格局、查清富烃凹陷下组合地层及烃源岩展布特征提供了良好的资料基础,为下一步深层油气勘探工作提供了有效指导。

深度学习网络在非常规油气开发中的应用研究

以深度学习为代表的人工智能已被公认为是石油勘探开发技术转型升级的关键核心技术。借助深度学习强大的学习能力,试井解释正在向模型自动识别及试井自动解释方向快速演化;早期的产量预测多基于已知的特征,从实测数据中自动提取特征的研究引发关注,仅基于井口压力的产量预测已取得积极进展;以多点地质统计为基础的数字岩心重建方法正被生成对抗网络所取代,但如何满足裂缝、孔隙度及渗透率等约束仍是难题;偏微分方程求解正经历着颠覆性变化,基于非线性方程的传统求解方法正迎来智能求解时代。基于物理本质,单一的神经网络结构正在向复杂网络结构演化。随着人工智能技术的不断发展,大型模型将成未来趋势。因此,相关研究多头并进,加强数据收集,构建大型模型,是我国未来智慧油气开发的核心任务。

BTA深孔连接器设计及油膜压力研究

针对BTA加工过程中刀具系统刚性不足和径向受力不平衡的问题,基于流体动压润滑原理设计一种BTA深孔连接器。连接器包括双桥应变片和可倾瓦块,利用油膜支撑刚度增大刀具系统的刚性,并通过实时调整油膜压力抵消同步检测的不平衡径向力。建立可倾瓦块的数学模型,推导出油膜厚度公式,进一步得出油膜压力的计算公式。基于Fluent软件对连接器进行流体仿真,采用单因素实验法,分析不同条件下可倾瓦块受到的油膜压力的变化规律。结果表明:BTA加工过程中,通过调节工件转速、切削液黏度、瓦块倾角和瓦块包角等参数调整油膜压力,进而实现增大刀具系统刚性和抵消不平衡径向力的目的。