A comparative study of the main factors controlling geohazards induced by 10 strong earthquakes in Western China since the Wenchuan earthquake in 2008

Determining the main controlling factors of earthquake-triggered geohazards is a prerequisite for studying earthquake geohazards and post-disaster emergency response.By studying these factors,the geomorphic and geological factors controlling the nature,condition,and distribution of earthquake-induced geohazards can be analyzed.Such insights facilitate earthquake disaster prediction and emergency response planning.The authors combined field investigations and spatial data analysis to examine geohazards induced by seismic events,examining ten earthquakes including the Wenchuan,Yushu,Lushan events,to elucidate the main control factors of seismic geohazard.The authors observed that seismic geohazard occurrence is usually affected by many factors,among which active nature of the seismogenic fault,seismic peak ground acceleration(PGA),topographic slope and geomorphic height differences,and distance from the fault zone and river system are the most important.Compared with strike-slip earthquakes,thrust earthquakes induce more high-altitude and high-speed remote landslides,which can cause great harm.Slopes of 0°–40°are prone to secondary seismic geohazards,which are mainly concentrated 0–6 km from the river system.Secondary geohazards are not only related to seismogenic fault but also influenced by the associated faults in the earthquake area.The maximum seismic PGA and secondary seismic geohazard number are positively correlated,and the horizontal and vertical ground motions play leading and promoting roles in secondary geohazard formation,respectively.Through the research,the spatial distribution of seismic geohazards is predicted,providing a basis for the formulation of emergency response plans following disasters.

Paleozoic Composite Petroleum System of North Africa:Hydrocarbon Distribution and Main Controlling Factors

North Africa, which is one of the main oil and gas producing regions in the world, is best known for its subsalt Paleozoic-Triassic reservoirs and Paleozoic source rocks. Hydrocarbon abundance varies greatly from one structural domain to another areally and from one stratigraphic interval to another vertically. Analyses of the essential elements and geological processes of the Paleozoic petroleum system indicate that the distribution of the Lower Silurian shale source rocks, the development of a thick Mesozoic overburden, the presence of the Upper Triassic-Lower Jurassic evaporite seal are the most important factors goveming the distribution of the Paleozoic-sourced hydrocarbons in North Africa. The Mesozoic sequence plays a critical role for hydrocarbons to accumulate by enabling the maturation of the Paleozoic source rocks during the Mesozoic-Paleogene times and preserving the accumulated hydrocarbons. Basins and surrounding uplifts, particularly the latter, with a thick Mesozoic sequence and a regional evaporite seal generally have abundant hydrocarbons. Basins where only a thin Mesozoic overburden was developed tend to have a very poor to moderate hydrocarbon prospectivity.

Enrichment model and major controlling factors of below-source tight oil in Lower Cretaceous Fuyu reservoirs in northern Songliao Basin,NE China

Based on the geochemical,seismic,logging and drilling data,the Fuyu reservoirs of the Lower Cretaceous Quantou Formation in northern Songliao Basin are systematically studied in terms of the geological characteristics,the tight oil enrichment model and its major controlling factors.First,the Quantou Formation is overlaid by high-quality source rocks of the Upper Cretaceous Qingshankou Formation,with the development of nose structure around sag and the broad and continuous distribution of sand bodies.The reservoirs are tight on the whole.Second,the configuration of multiple elements,such as high-quality source rocks,reservoir rocks,fault,overpressure and structure,controls the tight oil enrichment in the Fuyu reservoirs.The source-reservoir combination controls the tight oil distribution pattern.The pressure difference between source and reservoir drives the charging of tight oil.The fault-sandbody transport system determines the migration and accumulation of oil and gas.The positive structure is the favorable place for tight oil enrichment,and the fault-horst zone is the key part of syncline area for tight oil exploration.Third,based on the source-reservoir relationship,transport mode,accumulation dynamics and other elements,three tight oil enrichment models are recognized in the Fuyu reservoirs:(1)vertical or lateral migration of hydrocarbon from source rocks to adjacent reservoir rocks,that is,driven by overpressure,hydrocarbon generated is migrated vertically or laterally to and accumulates in the adjacent reservoir rocks;(2)transport of hydrocarbon through faults between separated source and reservoirs,that is,driven by overpressure,hydrocarbon migrates downward through faults to the sandbodies that are separated from the source rocks;and(3)migration of hydrocarbon through faults and sandbodies between separated source and reservoirs,that is,driven by overpressure,hydrocarbon migrates downwards through faults to the reservoir rocks that are separated from the source rocks,and then migrates laterally through sandbodies.Fourth,the differences in oil source conditions,charging drive,fault distribution,sandbody and reservoir physical properties cause the differential enrichment of tight oil in the Fuyu reservoirs.Comprehensive analysis suggests that the Fuyu reservoir in the Qijia-Gulong Sag has good conditions for tight oil enrichment and has been less explored,and it is an important new zone for tight oil exploration in the future.

Differential Hydrocarbon Enrichment and its Main Controlling Factors in Depressions of the Bohai Bay Basin Differential Hydrocarbon Enrichment and its Main Controlling Factors in Depressions of the Bohai Bay Basin

Significant differential hydrocarbon enrichment occurs in depressions in a petroliferous basin.There are multiple depressions in the Bohai Bay Basin, and each depression as a relatively independent unit of hydrocarbon generation, migration and accumulation, contains significantly different hydrocarbon generation conditions and enrichment degree. On the basis of previous documents and a large number of statistical data, this work comparatively analyzed the differential hydrocarbon enrichment and its major controlling factors in depressions of the Bohai Bay Basin. The results show that depressions in the Bohai Bay Basin have various hydrocarbon enrichment degrees, and can be categorized into four types, namely enormously oil-rich, oil-rich, oily and oil-poor depressions. In general, the enormously oil-rich and oil-rich depressions are distributed in the eastern part of the basin along the Tan-Lu and Lan-Liao faults, whereas depressions in the western part of the basin are poor in hydrocarbons. Moreover, the vertical distribution of hydrocarbons is also highly heterogeneous, with Pre-Paleogene strata rich in hydrocarbons in the northern and western depressions, Paleogene strata rich in hydrocarbons in the entire basin, and Neogene strata rich in hydrocarbons in the off-shore areas of the Bohai Bay Basin. From early depressions in onshore areas to the late depressions in offshore areas of the Bohai Bay Basin, the source rocks and source-reservoir-cap rock assemblages gradually become younger and shallower, and the hydrocarbon resource abundance gradually increases. Hydrocarbon supplying condition is the key factor constraining the hydrocarbon enrichment for different depressions,while the main source-reservoir-cap rock assemblage, sufficient hydrocarbons and the transportation capacity of faults control the vertical distribution of hydrocarbons. The main factors controlling hydrocarbon enrichment are different for different layers. The hydrocarbon supplying condition of source rocks is the key controlling factor, whereas the source-reservoir configuration, the main sourcereservoir-cap rock assemblages, and the fault transportation are the main factors of hydrocarbon enrichment in the Paleogene, Paleogene and Neogene, respectively.

Main Controls on Hydrocarbon Accumulation in the Paleozoic in Central Saudi Arabia

Sandi Arabia is renown for its rich oil and gas Mesozoic. However, the discovery of Paleozoic fields in resources with the bulk of the reserves reservo/red in the the late 1980s has encouraged further exploration in the Paleozoic. This paper reviews the salient features of the Paleozoic petroleum geology in central Saudi Arabia and discusses the main factors controlling hydrocarbon accumulation in the Paleozoic. The Lower Silurian Qusaiba hot shale is the principal source rock for the hydrocarbons discovered in the Ordovician to Permian reservoirs. Of them, the Permo- Carboniferous Unayzah and Upper Ordovician Sarah Formations have the best exploration potential. The key factors controlling hydrocarbon accumulation in the Unayzah Formation are migration pathways and reservoir petrophysics. The key factors controlling hydrocarbon accumulation in the Sarah Formation are reservoir petrophysics and the development of structural traps.

Main Controlling Factors and Accumulation Model of Chang 9 Reservoir in Northwest Ordos Basin, China

In northwestern Ordos Basin, the Triassic reservoir Chang 9 has favorable reservoir forming conditions, extensive reservoir development, and huge potential for oil exploration and exploitation. Studying the main controlling factors and accumulation model of Chang 9 reservoir in this area can provide a basis for the production targets, and assist in formulating reasonable development technology policy. In this paper, to explore and summarize the hydrocarbon accumulation model, the Chang 9 reservoir were analyzed from the aspects of oil source, fracture, oil migration, structure, lithology and reservoir physical properties for the main controlling factors in this area. Organic geochemical and geological comprehensive analysis that the oil-source of the Chang 9 reservoir in the northwest of Ordos Basin is derived from Chang 7 hydrocarbon source rocks. The fractures provide a sound channel for the "vertical multi-point filling" of the oil source from Chang 7 to Chang 9. The crude oil migrates vertically from Chang 7 to Chang 9, then expands horizontally to form a reservoir. Structures play an important role in controlling the distribution of reservoirs, the control by sand in small layer and physical property is also obvious. This paper creatively establishes the reservoir accumulation model of Chang 9 in northwest of Ordos Basin, which is characterized by Vertical multi-point filling, horizontal expansion becomes oil pool. It reveals the genetic mechanism of the development of Chang 9 multi-reservoir in the study area, which provides guidance for exploration and evaluation deployment.

Digital Instrumentation and Control System for Unit 5 ＆ 6 of YangJiang NPP

The article describes the digital instrumentation and control system for unit 5 ＆ 6 of YangJiang NPP, involving the overall I ＆ C （instrumentation and control） structure, the basic requirements and independent verification and validation. Advanced I ＆ C systems for YangJiang NPPs have to meet increasing demands for safety and availability. Additionally, the specific requirements coming from the nuclear qualification have to be fulfilled.

相空间重构后矿井涌水量序列地质学含义及其应用研究

目的为了确定相空间重构矿井涌水量序列的地质学含义并提高涌水量预测精度,方法以王行庄矿为例,在涌水量序列相空间重构后,对重构后相空间列向量与涌水量主控因素进行相关性分析,并在此基础上建立混沌理论与人工神经网络耦合(Chaos-ENN)的涌水量预测模型。结果结果表明:相空间的嵌入维数等于矿井涌水量主控因素个数;相空间的第1,2,4,5,6列向量分别与C_(2)tL_(7-8)含水层水位埋深、O_(2)m+Є_(3)ch含水层水位埋深、采空区面积、C_(2)tL_(1-4)含水层水位埋深、开拓长度具有较高的相关性,第3列与不易量化的其他综合因素有关;构建的Chaos-ENN涌水量预测模型在王兴庄矿的预测精度达到97.91%。结论涌水量序列重构后相空间的列向量具有明确的地质学含义。利用混沌理论可以量化涌水量预测模型中ENN输入层的个数及取值,所以仅需涌水量序列值就可以建立矿井涌水量预测的Chaos-ENN模型,该模型解决了涌水量预测中存在的主控因素难以确定和不易量化的难题,且预测精度高,具有较高的推广价值。

“三全育人”理念指导下热工控制系统试验与维护课程思政的教学设计与实施

对当前高职院校热工控制系统试验与维护课程的教学现状及问题进行分析。提出了以“厚德强技乐业、电力点亮人生”为思政主线的课程思政总体设计思路,从课程思政教学目标、教学体系、教学方法、教学实施、教学评价5个方面对高职院校热工控制系统试验与维护课程思政教学进行了改革探索。实践结果表明,热工控制系统试验与维护课程思政教学改革取得了良好效果,学生的电力报国情怀培育得以强化,人才培养质量显著提高,毕业生获就业单位广泛好评。

某型航空发动机主燃油控制系统频率特性研究

为研究某型航空发动机数控系统主燃油控制系统频率特性,基于力平衡方程和流量连续方程建立元件和系统的动态数学模型。在其稳态工作点附近采用小偏离线性化建立等压差模块、主燃油计量模块、停车控制模块和整个系统的传递函数,并通过Fluent流场仿真重点研究了关键元件的稳态液动力及影响因素。在此基础上建立了主燃油控制系统的Simulink仿真模型,研究了控制系统的频率特性和关键活门固有频率。结果表明:主燃油控制系统的频率特性与实际工程经验一致,稳定裕度较高;系统的固有频率与系统中固有频率最低的元件基本一致;当元件结构确定时,稳态液动力对固有频率的影响较大。研究结果为燃油控制系统频率域优化设计提供了理论支持。

Fractal Characteristics and Main Controlling Factors of High-Quality Tight Sandstone Reservoirs in the Southeastern Ordos Basin

Due to the complex conditions and strong heterogeneity of tight sandstone reservoirs,the reservoirs should be classified and the controlling factors of physical properties should be studied.Cast thin section observations,cathodoluminescence,scanning electron microscopy(SEM),X-ray diffraction(XRD),and high-pressure mercury injection(HPMI)were used to classify and optimize the reservoir.The Brooks-Corey model and stepwise regression were used to study the fractal dimension and main controlling factors of the physical properties of the high-quality reservoir.The results show that the reservoirs in the study area can be divided into four types,and the high-quality reservoir has the best physical properties and pore-throat characteristics.In the high-quality reservoir,the homogeneity of transitional pores was the best,followed by that of micropores,and the worst was mesopores.The porosity was controlled by depth and kaolinite.The model with standardized coefficients is y=12.454−0.778×(Depth)+0.395×(Kaolinite).The permeability was controlled by depth,illite/montmorillonite,and siliceous cement,and the model with standardized coefficients is y=1.689−0.683×(Depth)−0.395×(Illite/Montmorillonite)−0.337×(Siliceous Cement).The pore-throat evolutionary model shows that the early-middle diagenetic period was when the reservoir physical properties were at their best,and the kaolinite intercrystalline pores and residual intergranular pores were the most important.

Evaluation and Application of Flowback Effect in Deep Shale Gas Wells

The pivotal areas for the extensive and effective exploitation of shale gas in the Southern Sichuan Basin have recently transitioned from mid-deep layers to deep layers.Given challenges such as intricate data analysis,absence of effective assessment methodologies,real-time control strategies,and scarce knowledge of the factors influencing deep gas wells in the so-called flowback stage,a comprehensive study was undertaken on over 160 deep gas wells in Luzhou block utilizing linear flow models and advanced big data analytics techniques.The research results show that:(1)The flowback stage of a deep gas well presents the characteristics of late gas channeling,high flowback rate after gas channeling,low 30-day flowback rate,and high flowback rate corresponding to peak production;(2)The comprehensive parameter AcmKm1/2 in the flowback stage exhibits a strong correlation with the Estimated Ultimate Recovery(EUR),allowing for the establishment of a standardized chart to evaluate EUR classification in typical shale gas wells during this stage.This enables quantitative assessment of gas well EUR,providing valuable insights into production potential and performance;(3)The spacing range and the initial productivity of gas wells have a significant impact on the overall effectiveness of gas wells.Therefore,it is crucial to further explore rational well patterns and spacing,as well as optimize initial drainage and production technical strategies in order to improve their performance.

基于相变蓄冷的核电厂主控室非能动冷却系统

为提高现有核电厂主控室紧急可居留系统的蓄冷能力及热舒适性水平,提出了基于定形相变蓄冷材料的核电厂主控室非能动冷却系统。基于主控室热负荷分布情况,该冷却系统在主控室顶板与吊顶之间、内墙面、地板底面及循环风道内,针对性地布置相应的含有定形相变材料的非能动冷却装置,进而实现事故工况下对主控室温度的精确控制。该非能动冷却系统无需引入额外冷源和管道,可靠性强,同时不破坏主体结构,且可灵活布置,解决了现有主控室非能动热阱时间余量小、热舒适性差的问题。

大体积混凝土BIM智能温控系统及方法研究

研究目的:针对超高主塔大体积混凝土在施工过程中易因混凝土温度超限导致裂缝的问题,研究BIM智能温度控制系统及方法,选择REVIT软件建模并与大数据平台二次集成开发,利用4G无线网络通信设备、工业集成软件服务器和计算机等建立智能温控系统,并搭载人工智能控制算法,进行大体积混凝土全过程温度的超前预测和智能决策。研究结论:(1)建立了大体积混凝土原材料及出机温度监控子系统、混凝土入模及硬化过程温度监控子系统,通过4G无线传输接收测温元件数据,对混凝土施工全过程温度进行动态监测;(2)在BIM模型中标记测温点位置和同步直观反映温度变化,并进行超限预警;(3)对大体积混凝土的出机温度、入模温度及硬化过程温度进行超前预测和智能决策,提供原材料温度控制、水冷系统控制等系列决策手段,确保施工过程温度满足规范要求;(4)本文所述控制系统及方法已成功应用于马鞍山公铁两用长江大桥超高主塔大体积混凝土温控中,取得良好应用效果。

国产水下生产系统在渤海油田的首次应用

为了突破外国的技术限制,实现国产化水下油气生产技术的顺利实现,因此有必要开展对国产化水下油气生产技术的研究。文章概括了中国水下油气生产装置的研究开发历程,并阐述了全水式、电液复合式和全电式等水下生产系统的主要运行模式和特征,并归纳出各生产装置的主要优势与缺陷。以流花11-1油气田、流花16-2/20-2/21-2油田群、陵水17-2气田等为主要技术平台,进行了渤海首次国产水下油气生产系统的试验应用,基本概括了渤海首次的水下油气工程技术特征,并对通讯不稳定问题解决方案进行验证,最后并对其应用前景进行了展望。

船舶主机基座系统振动分析及控制技术

船舶主机基座系统是由基座结构和控制系统等2个部分组成。在主机持续工作的情况下,产生的交变载荷会通过基座系统传递,引起船体结构振动,可能对船体结构的安全构成威胁。通过合理设计基座结构和控制系统,可有效控制船舶主机传递到船底结构的振动,以满足更高的减振要求。首先介绍船舶主机引起振动的机理和振动分析方法,详细综述船舶主机基座结构、被动控制系统和主动控制系统的减振机理和优化研究成果,并对未来的研究进行一定的展望,为船舶主机基座系统的减振设计提供有益的参考。

膏盐岩-碳酸盐岩共生层系岩石微相及储层特征——以阿布扎比B油田侏罗系Arab组为例

为探究膏盐岩–碳酸盐岩共生层系强非均质性问题,基于岩芯及测井资料,探究阿布扎比B油田Arab组岩石微相类型,分析各类微相的储层特征及优质储层主控因素。Arab组可识别出12种微相类型(MF1~MF12),微相类型及组合指示其为局限–蒸发背景下萨布哈潮坪–潟湖–障壁滩沉积体系。微相类型控制储层品质,其中MF2及MF9~MF12孔喉较粗,连通性好,孔隙度和渗透率较高,是储层发育有利微相类型。MF2和MF10发育白云岩储层,储集空间以晶间孔、残余粒间孔及粒内溶孔为主;MF9,MF11和MF12发育颗粒灰岩储层,储集空间以粒间(溶)孔、铸模孔及粒内溶孔为主。相对海平面的震荡性变化导致各沉积相带在纵向上的有序叠置,不同沉积相带之间或同一沉积相带内微相类型及成岩作用的差异性是Arab组储层强非均质性的根本原因。障壁滩和潮上带是优质储层发育的有利相带,其中障壁滩相优质储层原生粒间孔保持较好,并叠加显著的早期暴露溶蚀,导致次生孔隙的产生和孔隙结构的改善;潮上带优质储层的发育受控于早期白云石化和准同生溶蚀作用,白云石化改善孔隙结构,有利于早期孔隙保存,分散状硬石膏的早期溶蚀产生大量次生孔隙,显著地改善了储层物性。

井下主通风控制系统的配置和功能分析

为进一步实现井下主通风系统的自动化控制,结合轩岗煤矿的实际情况,在原有通风系统的基础上增加了PLC(Programmable Logic Controller,可编程逻辑控制器)控制单元和变频调速功能,对井下主通风控制系统进行整体配置。从主控模块、变频系统、传感器等多个角度着手,详细探讨了煤矿井下主通风系统各个功能模块的配置和落实,并对该系统进行了实际测试。测试结果显示,该系统能够根据瓦斯体积分数的变化,对通风机运行情况予以快速响应和智能调整,表明其整体性能良好,具有一定的应用价值。

胡家河煤矿综放工作面矿压显现规律预测及主控因素研究

现有工作面矿压显现规律预测方法中,基于数值模拟与统计回归的方法无法实现对工作面矿压显现规律的实时精准预测,深度学习方法存在超参数较多且难以设置、模型训练速度慢等问题。针对上述问题,以胡家河煤矿402102回采工作面采动过程中监测到的煤体内部应力变化时序数据为基础,将基于粒子群优化的门控循环单元(PSO-GRU)应用到回采工作面矿压显现规律预测中。采用PSO算法对GRU进行优化,构建PSO-GRU模型,实现对超参数的自动寻优,从而提高GRU的训练速度和预测精度。以预测结果为依据,采用层次分析法建立402102回采工作面矿压主控因素评价指标体系,将顶板条件、回采工艺、煤层赋存、地质构造确定为影响工作面矿压的一级指标,进一步细分出具有代表性的14个二级指标。测试结果表明:(1)与未经优化的GRU模型相比,PSO-GRU模型的均方误差(MSE)降低了83.9%,均方根误差(RMSE)降低了59.8%,平均绝对误差(MAE)降低了59.0%,决定系数R2提升了28.9%。(2)PSO-GRU模型对矿压数据预测的拟合度达0.980以上,具有良好的非线性拟合能力和泛化能力。(3)地质条件中的煤层赋存因素对回采工作面矿压的影响最大,权重为0.47;可人为干预的影响因素中工作面推进速度对矿压的影响最大,权重为0.13。

基于RFID技术和FPGA主控模块的智能图书测距系统设计

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