In the Neoproterozoic era, the breakup of the Rodinia supercontinent had a profound impact on different aspects of Earth; yet, the precise driving mechanism behind this event has been a source of ongoing controversy. The Tarim block, as a crucial component, presents an opportunity to gain valuable insights into the breakup process through its tectonic-sedimentary evolution history and dynamic background. However, the comprehension of basin evolution is limited due to the presence of an ambiguous prototype basin during the late Neoproterozoic and its intricate interconnections with surrounding blocks. In this contribution, we integrate detailed field observations, U-Pb dating of detrital zircon and rutile, and trace element analysis of detrital rutile to elucidate the source-to-sink relationships and the tectonic setting of Ediacaran sedimentary strata in the Aksu area (northern Tarim block, China). Detrital zircon age spectra exhibit consistent distributions with ages between - 850 and 600 Ma and between - 2100 and - 1800 Ma. Rutile age groups however exhibit an abrupt transition between the lower member of the Sugatbrak Formation and the succeeding upper member to the Qigebrak Formation in the basin, with ages between - 1800 and - 900 Ma and nearly identical to those between - 2100 and - 1800 Ma. Calculated Zr-in-rutile temperatures and Cr-Nb compositions imply that the majority of the detrital rutiles were sourced from amphibolite facies metapelites, with an abrupt transition from amphibolitic schist to amphibolite-granulite facies for the - 1800 Ma group grains. Provenance tracing shows that the detrital sediments of the lower Sugatbrak Formation are sourced from both the Central Tianshan and the Tarim blocks, and that the overlying strata have a single source in the Tarim block. A corresponding change from syn-rift detrital facies to a shallow-marine environment in on a passive continental margin is suggested in terms of depositional setting. In light of prior published evidence from petrology, geochronology and paleomagnetism, we propose that the Neoproterozoic northern Tarim margin was affected by a protracted subduction zone retreat. Associated back-arc spreading eventually was responsible for the opening of the southern Tianshan Ocean and rifting of the Central Tianshan block from the Tarim block in the late Ediacaran. This development ultimately prevented detrital material from the Central Tianshan block from reaching the northern Tarim depocenters as the latter evolved into a passive continental margin.

Abstract The Cenozoic sediments are very thick in the southwest Tarim Basin and very thin in the northwest, but what controls these variations is unclear. Here, we use two‐dimensional thermo‐mechanical models to investigate how the lateral variations in rheological strength and depletion density of cratonic lithosphere mantle affect the cratonic basin deformation. Model results show that the basin basement uplift occurs above either the region with crustal thickening or high depletion in the mantle. A model with a stronger and density‐depleted northern half of cratonic lithosphere mantle in the context of compression matches the differential Cenozoic subsidence and deformation observed in the Tarim Basin well. We propose that a Permian plume led to the lateral heterogeneity of the lithosphere mantle under the Tarim craton, and the modified lithosphere mantle characteristics caused the differential Cenozoic sediment thickness in the Tarim Basin.

In this paper, a novel green and cost-effective synthesis method in this field is presented. Mesoporous γ-alumina was obtained by inorganic in situ crystallization, and sodium aluminate as an aluminum origin was abstracted from red mud. The influence mechanism of the reactant ratio of NaHCO3 to NaAlO2, the reaction temperature and the concentration of the template was systematically investigated. As indicated by the results, the obtained mesoporous γ-alumina possesses extensive specific surface areas, narrow pore size distribution, nearly spherical particle morphology and wormlike structure pores. This green and economical synthesis method can be used for the preparation of alternative mesoporous or various porous materials as well.

The terminal Ediacaran shallow marine microbialites are significant for paleo-environment reconstruction and petroleum exploration. Their depositional and paleo-environmental characteristics during high-frequency sea-level fluctuations were paid less attention, which limited the understanding of their evolution and related reservoir characterization. Microbialites from the fourth member of the upper Ediacaran Dengying Formation, Gaoshiti-Moxi area, Sichuan Basin, SW China are important records for studying their lithofacies associations and paleo-environmental constraints in high-frequency depositional sequences. Petrographic and geochemical analyses ( in-situ major and trace elements and carbon and oxygen isotopes) indicate microbialites depositional and paleo-environmental evolution on a rimmed platform within a fourth-order depositional sequence. From late TST (transgressive systems tract) to early HST (highstand systems tract), thick-bedded dark-grey dolomudstone-thin-bedded spotted thrombolite dominates the platform margin; while thick-bedded dark-grey dolomudstone-thin bedded dark-grey wavy stromatolite dominates the platform interior. From late HST to early TST of the next fourth-order sequence, the platform margin is dominated by thick-bedded spotted thrombolite—dolograinstone, while the carbonate interior is dominated by thin-medium-bedded layered thrombolite—light-grey wavy stromatolite. Salinity correlates well with microbialite lithofacies associations: the platform interior layered thrombolite and wavy stromatolite enriched lithofacies associations are characterized by higher salinity than that of the platform margin spotted thrombolite enriched lithofacies associations. The microbialite lithofacies associations are less constrained by redox: platform interior layered thrombolite and wavy stromatolite enriched lithofacies associations are slightly more reduced than the platform interior spotted thrombolite enriched lithofacies associations. The redox analysis of the microbialites also indicates low oxygen levels of shallow marine in the study area during terminal Ediacaran, with possible oxygenation at the Ediacaran-Cambrian boundary. The study suggests that the terminal Ediacaran microbialite development was controlled by both high-frequency sea-level fluctuations and paleo-environmental factors such as salinity and redox. Platform margin spotted thrombolitic reefs from late fourth-order HST to next early fourth-order TST serve as favorable microbialite reservoirs. Platform interior layered thrombolites and wavy stromatolites are regarded as potential reservoirs, which deserve more detailed depositional-paleo-environmental research.

The past decade has witnessed a breakthrough in the gas exploration of deep marine carbonates of the central Sichuan Basin. Deep faults research has also attracted increasing attention, as faulting plays an important role in reservoir control. Previous studies have suggested a developed series of high-angle strike-slip fault systems in the central Sichuan Basin, but correlated exploration activities are limited, as distribution rules and dynamic mechanisms remain unclear. In this study, the spectral decomposition coherence method was used to describe the geometric and kinematic characteristics of these strike-slip faults. Using a comprehensive analysis technique to assess the strike-slip fault tectonic activity history, the formation and evolution processes of strike-slip faults and their control on hydrocarbon distribution were examined. The results showed that the deep strike-slip fault system, mostly distributed in the Dengying Formation, can be divided into four stages, three levels, and three groups of orientation, which controlled the structural framework and shape of the central Sichuan area, as well as the zoning from north to south, and blocking from west to east. The faults showed features of layered deformation and staged evolution in the vertical direction. The segmentation of strike-slip faults strongly controls the quality of fractured vuggy reservoirs. Reservoirs of the hard-linked zone of the strike-slip fault are the most developed, followed by those of soft-linked segments, with translational sections of the strike-slip fault being relatively undeveloped. Strike-slip faults are important hydrocarbon migration paths, and their multistage activities have different controlling effects on hydrocarbon accumulation.

The Middle-Lower Ordovician Yingshan Formation is an important reservoir unit in the Tazhong oil field (Tarim Basin, northwestern China). This oil field is deeply buried (>5500 m [>18,045 ft]) and has endured a complex diagenetic history. To understand the mechanisms of reservoir formation, we conduct a broad portfolio of geochemical analyses on the calcite cements that fill the pores and fractures in samples retrieved from wells penetrating the Yingshan Formation. Our results identify six diagenetic episodes, each associated with the emplacement of different cements, varying from marine conditions (C1), nearsurface to shallow burial (C2), intermediate-to-deep burial (C3 and C4), and infiltration of the formation with mixing of the underlying basinal brines with meteoric waters and hydrothermal fluids (C5 and C6) along northeast-trending strike-slip faults. The productive wells display evidence of a strong burial diagenetic overprint linked to exotic fluids (C5 and C6) along fractures. We conclude that eogenetic meteoric waters were vital in producing early diagenetic porosity within the Tazhong reservoir, which was subsequently refined by late burial (hyposons for the evolution of other geodynamically active cratonic basins.

This paper has conducted a high‐resolution characterization of a deeply buried carbonate karst in the Tarim Basin of China by utilizing the FMI (Full‐bore Formation Micro Image) method integrated with seismic data, drilling cores and thin sections. It was found that the type and scale of wellbore karst architecture are mainly controlled by karst paleogeomorphology and vertical faults. The karst highlands and slopes, respectively, develop vadose karst and phreatic karst, with different compositions of karst elements. In terms of the karst thickness in the wellbore, the vertical fault development zone is almost twice that of the non‐development zone, both for the vadose karst and phreatic karst. Furthermore, the vertical fault is also able to promote the development of mixing karst. The mixing zone is located 55 m below the water table, with a strata thickness of approximately 25 m, a net reservoir thickness of 5 – 15 m, and an average porosity of 4%–8%, which serves as an effective hydrocarbon reservoir in the Yingshan Formation. The results will provide insights into the vertical division of karst reservoir and help predict reservoirs using well logs.

根据铸体薄片、扫描电镜、黏土矿物X线衍射、地层水及物性参数等资料,分析塔里木盆地库车坳陷依奇克里克构造带下侏罗统阿合组砂岩的岩石学、成岩作用及地层水等特征,结合依奇克里克构造带阿合组热史—埋藏史、裂缝和断层分布规律,探讨依奇克里克背斜轴部和翼部阿合组砂岩储层成岩流体封闭性特征及其油气保存条件.结果表明:依奇克里克背斜轴部阿合组砂岩自生高岭石体积分数较高,背斜翼部的较低;背斜轴部与翼部阿合组砂岩成岩演化序列出现差异的时间距今约为5 Ma;相较于背斜翼部,背斜轴部阿合组地层水中钠氯系数及脱硫系数较高,变质系数较低;背斜轴部阿合组砂岩的成岩流体系统封闭性比背斜翼部的弱,影响天然气聚集.该结果对预测依奇克里克构造带油气藏分布具有指导意义.

Several giant oilfileds have been discovered during recent exploration in the Ordovician carbonates in zone between the Awati and Manjiaer depressions, Tarim Basin, China. These oilfields are deeply buried (> 7000 m), and most productive wells are found adjacent to fault zones, suggesting faults may play a crucial role in reservoir development. Here, we use petrographic, microanalytical and geochemical techniques on different stages of void-filling calcite cements to decipher the tectonic-fluid evolution history. Vugs are generally occluded by V1 and V2 calcite cements, which precipitated from marine and burial diagenetic fluids. Two major episodes of fluid in-vasion are evident in each set of fractures from Middle Ordovician strike-slip faults (F1) to Late Devonian to the Permian strike-slip faults (F2). The sub-horizontal fracture-filling F1 calcite cements show the involvement of near-surface marine to marine-evolved brines, given that delta(18)Ocarb, restored delta(18)Ow values and rare earth element and yttrium (REY) profiles of F1-1 calcite cements are comparable to Ordovician seawater. The F1-2 calcite cements are characterized by negative delta(18)Ocarb, positive restored delta(18)Ow, and apparent Ce positive anomalies. The sub-vertical fracture-filling ferroan F2-1 calcite cements with fluorescence show the highest restored T(delta(47)) (up to 125 ?C), high restored delta 18Ow values (up to +7.0%o VSMOW), and an enrichment in MREE, which is consistent with an origin from hot hydrocarbon-bearing basinal brines. The subsequent F2-2 calcite cements may have precipitated during the Late Permian from mixing of basinal brines and deeply circulated meteoric water, as suggested by significantly negative delta(18)Ocarb values, cooler restored T(delta(47)), negative restored delta(18)Ow values (down to-5.9%o VSMOW), and flat REY patterns. The Sr-87/Sr-86 ratios of calcite cements are similar to coeval seawater. This study highlights the importance of fault-related fluid circulation in the development of a hydrocarbon reservoir, and may be applicable to other deep carbonate-hosted reservoirs.

The deep marine carbonate reservoir in the central part of the Sichuan Basin is a hot field for oil and gas exploration. Deep strike-slip faults were developed in this area, and strike-slip faults played an important role in the large accumulation of hydrocarbons in carbonate rocks. Therefore, the fine interpretation of deep strike-slip faults based on seismic data is the key to identifying "sweet spots" in deep carbonate reservoirs. Filtering and spectral decomposition techniques were used to enhance the signal-to-noise ratio of the seismic events and improve the accuracy of fault recognition. Furthermore, the geometric and kinematic characteristics, formation mechanism and influence on hydrocarbon accumulations of strike-slip faults in the central Sichuan Basin have been clarified. Three structural styles of strike-slip faults were developed in the deep layers of the study area: steep-dip vertical faults, flower-like structures, and Y-shaped fault combinations. The fault system were divided into basement structural sequence (Pre-Sinian), lower structural sequence (Sinian-Permian), and upper structural sequence (Triassic and its upper strata). Strike-slip faults were mainly distributed in the lower structural sequence. Strike-slip faults developed in the east-west and north-west directions have right-lateral properties, while faults developed in the north-east direction have left-lateral properties. The analysis of the growth index of faults in different periods showed that the faults in central Sichuan Basin had a migration path from south to north and from west to east. In addition, the strike-slip faults of three stages, three grades and three groups of directions in central Sichuan region are mainly distributed in strips along the east-west direction, which reflect the differences in the structural patterns of the southern and northern regions. The formation of the three-stage faults was related to the weak zone of pre-existing structures in the basement, the two tension-torsion actions during the deposition of the Ordovician and Permian, and the compression-torsion actions on the periphery of the basin in the Indosinian Movement and the later stages.

Microbial communities regained prominence in the Cambrian after a prolonged downturn in the Neoproterozoic, but the reasons for their revival are unclear. The earliest microbialites formed during this period within the Tarim Basin are well displayed in the Xiaoerbulake Formation in the Keping area. Major, trace, rare earth element (REE) analyses were carried out using samples collected from two sections of the Xiaoerbulake Formation which present two different palaeogeographical settings, namely, the intraplatform and platform margin. The samples were divided into seven groups based on their REE + Y (yttrium) distributions. Among these, the YG3, YG4, and PG3 groups correspond to microbial boom phases. The high contents of Al and other nutrient elements (e.g., P, Ni, U, Cu, Fe, Mn) in these three groups indicate that the microbial booms are controlled by nutrient concentration of different sources. In relatively deep‐water settings, aeolian dust and suspension particles modified the seawater geochemical characteristics to form shale‐like (REE + Y)N patterns. The nutrient‐rich fine‐grained deposits were blown up by storms and released nutrients. This eutrophication ultimately promoted microbial development and is demonstrated by light rare earth element enrichment patterns. In shallow‐water environments, microbes seemed to prefer quiet conditions, with sufficient nutrients provided by fluvial influx. In contrast, excess clastic materials inputs, be they carbonate or terrigenous debris, are unfavourable to the development of microbialites. Hence, it is expected that seawater REE preserved in ancient carbonates are capable of providing information on the impacts of seawater geochemical conditions on the evolution of microbialites.

图神经网络为属性网络数据挖掘提供融合利用结构信息和属性信息的方法,但是在现阶段基于图自动编码器进行无监督属性网络异常节点检测时,常将正常节点子属性插值形成的节点误识别为异常节点,导致方法的假负率较高.针对上述问题,文中提出基于变分图自编码器的异常节点检测方法.模型包含两个编码器和一个解码器,利用一个编码器和一个解码器构成的变分自编码器模型,重建原始输入数据,再利用解码器和第二个编码器,使模型学习到不包含异常节点数据的网络隐层表达.通过双变分自编码器学习正常节点子特征,并利用重建误差作为节点的异常度量,将由正常节点子特征构成的正常节点判别为正常节点.在真实网络数据集上的实验表明,文中方法能有效进行属性网络异常节点检测.

Hydrothermal dolomitization is an important diagenetic process that affects the quality of carbonate reservoirs. While geochemical modeling is a useful tool to improve our understanding of this process, comparatively little research has been focused on producing reservoir intervals. This study examines deeply buried (over 4500 m deep), Lower Ordovician dolomitized limestones (more than 50 m revealed by the borehole) in an exploration well in the Tazhong Uplift, Tarim Basin. The well penetrated a fault zone that was affected by extensive hydrothermal activity during the Permian. Batch geochemical modeling and reactive transport modeling (RTM) were used to evaluate the potential sources of hydrothermal fluid and the associated mechanisms that resulted in a relatively restricted distribution of dolomitization in the study area. Simulation results show that the RTM, which can include geological heterogeneity, provides more reliable constraints for the volume of hydrothermal fluids required for the observed scale of dolomitization, compared to batch geochemical modeling. According to the simulation results, the interstitial fluids released from underlying Cambrian formations due to high pressure and high temperature are not the only source of hydrothermal dolomitization. Other mechanism like long-lasting recharge of seawater-derived basement brines may be took place. Scenario simulations also indicate that the patterns of hydrothermal dolomitization and porosity distributions are strongly related to permeability heterogeneity in the formation. This study shows the ability and feasibility of geochemical modeling as a tool to quantitatively evaluate and further understand hydrothermal dolomitization processes, which are also helpful for other similar geological process research. However, reliable and detailed geological information, geological constrains, especially geological heterogeneity distributions, are crucial to achieve beneficial conclusions.

For the under-sampled imaging infrared search and tracking system which F lambda/d<2, the energy of point target was concentrated on a single pixel. Due to the spatial non-uniformity of intra-pixel sensitivity (IPS) for focal plane array, the calculation accuracy of energy and centroid for point target would be reduced. Light spot scanning test and numerical simulation could effectively characterize and analyze the IPS. but the system and model were highly complex and time-consuming, moreover, experimental tests couldn't analyze the relationship between the spatial non-uniformity of the IPS and the parameters of photo-detector. Aimed at the above problem, Monte Carlo methods were used to simulate the IPS of HgCdTe infrared focal plane array, and the influencing factors of its spatial non-uniformity were analyzed. The results showed that the spatial non-uniformity of IPS can be reduced by reducing the pixel pitch or increasing the thickness of absorber. With the increased in wavelength, the spatial non-uniformity of IPS increased slightly. The results of simulation and analysis are of great significance for improving the measurement accuracy of high energy concentration point target.

Organic acids are important agents in the alteration of deep reservoirs. It is difficult, however, to assess the impact of organic acid alteration on deep reservoirs because different dissolution processes may occur during diagenesis. This study simulated the dissolution of three different types of reservoir rocks by acetic acid in a closed system and compared the mineral and elemental composition, surface morphology, pore structure, and water chemistry variations of the initial and altered samples. The study demonstrated that both micrite and sucrosic dolostone are strongly dissolved, losing about 20%–30% of their initial rock sample weights. Observation under SEM showed that the limestone dissolved homogenously, whereas the dolostone showed honeycomb-like dissolution. Both carbonate samples showed the development of large voids, including holes and cavities of micrometer scale, but nanopores of various sizes were blocked. In contrast, lithic arkose was heterogeneously altered, losing a weight proportion of about 13% by dissolution of calcite cement. These micrometer-scale microfissures were developed, but those nanometer-scale pores just varied in a narrow range of sizes. The volume increase in all three reservoir types is mainly attributed to the dissolution of carbonate minerals. In deep reservoirs, in situ generated organic acids can enlarge existing cavities in carbonates and develop microfissures in sandstones. The microfissure porosity in sandstone is limited but can increase through other geological processes such as overpressure. More importantly, these acids can maintain the acidity of pore waters, inhibit the precipitation of dissolved minerals, and help to preserve reservoir porosity. Although temperature plays an insignificant role in laboratory simulations, it influences both the generation and destruction processes of organic acids in deep reservoirs on geologic time scales and, thus, warrants further attention. The results provide a basis for recognizing the typical patterns of organic acid dissolution on different reservoir rocks and further suggest the potential role of organic acids in the formation and preservation of secondary porosity in deeply buried reservoirs.

通过分析露头剖面、岩石微观组构及主量元素等特征,探讨了陆良彩色沙林成景地层沉积环境、成岩作用及景观形态、颜色成因.研究结果表明:(1)彩色沙林成景地层为茨营组,该组沉积环境为扇三角洲相、辫状河相及滨浅湖亚相,其中砾石成分主要为碎屑岩及变质岩,磨圆度及分选性较差,砂岩类型主要为中细岩屑砂岩,颗粒以点接触为主;(2)研究区茨营组砂岩在同生成岩阶段至早成岩阶段A期形成的铁、锰氧化物是影响砂岩固结的关键因素.铁、锰氧化物及有机质含量及分布使砂岩颜色改变;(3)茨营组的沉积环境、成岩作用及构造作用是导致岩石形态及颜色变化的主要因素.

The middle Cambrian is an important period for the decline of metazoans and the resurgence of microbialites. Based on the analysis of carbon and oxygen isotopes, detrital zircon U-Pb dating, and geochemical analysis, the middle Cambrian DICE (Drumian carbon isotope excursion) event was identified and its relationship with microbialites and sea-level changes was discussed in the Tarim Basin. The DICE event has a negative shift in delta C-13 from 0 parts per thousand to -3.2 parts per thousand. About 15 m below the DICE, the youngest age of the detrital zircon was 504.5 Ma, which was consistent with the age of the DICE event. Stromatolites are abundant and agnostoid trilobite Ptychagnostus atavus is absent in the Keping area. The DICE event corresponds to the occurrence of hemispherical stromatolites in the shallow-water platform. Lithologic association and terrigenous clastic index show that the marine transgression and condensation layer occurred during the DICE event, which may be synchronized with organic matter oxidation when stratified water masses overturned during transgression.

近年来,随着Web 2.0的普及,使用图挖掘技术进行异常检测受到人们越来越多的关注.图异常检测在欺诈检测、入侵检测、虚假投票、僵尸粉丝分析等领域发挥着重要作用.在广泛调研国内外大量文献以及最新科研成果的基础上,按照数据表示形式将面向图的异常检测划分成静态图上的异常检测与动态图上的异常检测两大类,进一步按照异常类型将静态图上的异常分为孤立个体异常和群组异常检测两种类别,动态图上的异常分为孤立个体异常、群体异常以及事件异常这3种类型.对每一类异常检测方法当前的研究进展加以介绍,对每种异常检测算法的基本思想、优缺点进行分析、对比,总结面向图的异常检测的关键技术、常用框架、应用领域、常用数据集以及性能评估方法,并对未来可能的发展趋势进行展望.

The significant Late Mesozoic thinning of lithospheric mantle in eastern China caused the formation of many basins and intensive volcanism. Crust exhumation process is a crucial part of supracrust response of lithosphere destruction. It has been studied in order to constrain the model of Late Mesozoic thinning of lithospheric mantle. The Sulu orogenic belt and the Jiaobei Terrane underwent a substantial exhumation process in Early Cretaceous, and though many studies have been carried out to investigate its exhumation history, it is still lacking understanding. Extensional terrestrial domain of the Jiaolai Basin was formed along with the Early Cretaceous exhumation of the Jiaobei Terrane and the Sulu orogenic belt. It provides an ideal research object for studying the exhumation process of Jiaodong Peninsula in Early Cretaceous because of the continuous sedimentary record in the basin. In this study, we analysed detrital zircon geochronology of three sandstone samples from Early Cretaceous sediments in north‐eastern part of the Jiaolai Basin. Detrital zircon age spectrums indicate that zircon ages consist mainly of six clusters, and they comprise Neoarchean ages, Palaeoproterozoic ages, Neoproterozoic ages, Triassic ages, Jurassic ages, and Early Cretaceous ages. The study shows that the Jiaobei Terrane and the Sulu orogenic belt served as source areas that provided detrital materials for Early Cretaceous strata in the Jiaolai Basin. Our results, along with those of previous studies, suggest that Jiaobei Terrane and the Sulu orogenic belt in Jiaodong Peninsula had discrepant exhumation history in Early Cretaceous.