The Neogene Shawan Formation in the Chepaizi Uplift of the Junggar Basin(NW China)has obtained high oil flow,demonstrating a good potential for oil and gas exploration.The multi-source hydrocarbon generation backgroun...The Neogene Shawan Formation in the Chepaizi Uplift of the Junggar Basin(NW China)has obtained high oil flow,demonstrating a good potential for oil and gas exploration.The multi-source hydrocarbon generation background and strong tectonic activity have led to the simultaneous production of heavy oil and light oil from multi-layer in the area,which makes it very difficult to identify oil origins,presently,the hot debate on the oil origins needs to be clarified.In this paper,due to the selective consumption of different types of compounds in crude oils by severe and intense biodegradation,the commonly used oilsource correlation tools are ineffective or may produce misleading results,this study adopted a biomarker recovery method based on the principle of mass conservation that uses the sum of the mass of the residual biomarkers and their corresponding biodegradation products to obtain the mass of the original biomarkers,improving the reliability of oil origins determination.Based on the nature and occurrence of crude oils,the investigated oils are subdivided into three types,Group A,Group B and Group C.Group A,light oils occurred mainly in lower structure Neogene Shawan Formation in the western Chepaizi Uplift,while Group B,heavy oils occurred mainly in higher structure Neogene Shawan Formation in the western Chepaizi Uplift.The two types of crude oils may come from the mixed source of Jurassic Badaowan Formation source rocks(J_(1)b)and Paleogene Anjihaihe Formation source rocks(E_(2-3)a)in the Sikeshu Sag,and Jurassic Badaowan Formation source rocks(J_(1)b)are the main source of crude oils.Group C,heavy oils occurred mainly in Neogene Shawan Formation in the eastern Chepaizi Uplift,showing good correlation with the Permian(P_(1)f and P_(2)w)source rocks in the Shawan Sag.At the same time,by combining stable carbon isotope and parameters related to triaromatic steroids,the accuracy of the oilsource correlation results by biomarker recovery method was further verified.展开更多
The global exploration investment, new oil and gas discoveries, exploration business adjustment strategies of oil companies in 2021, and future favorable exploration domains are systematically analyzed using commercia...The global exploration investment, new oil and gas discoveries, exploration business adjustment strategies of oil companies in 2021, and future favorable exploration domains are systematically analyzed using commercial databases such as IHS and public information of oil companies. It has been found that the world oil and gas exploration situation in 2021 has continued the downturn since the outbreak of COVID-19. The investment and drilling workload decreased slightly, but the success rate of exploration wells, especially deepwater exploration wells, increased significantly, and the newly discovered reserves increased slightly compared with last year. Deep waters of the passive continental margin basins are still the leading sites for discovering conventional large and medium-sized oil and gas fields. The conventional oil and gas exploration in deep formations of onshore petroliferous basins has been keeping a good state, with tight/shale oil and gas discoveries made in Saudi Arabia, Russia, and other countries. While strengthening the exploration and development of local resources, national, international, and independent oil companies have been focusing on major overseas frontiers using their advantages, including risk exploration in deep waters and natural gas. Future favorable exploration directions in the three major frontiers, the global deep waters, deep onshore formations, and unconventional resources, have been clarified. Four suggestions are put forward for the global exploration business of Chinese oil companies: first, a farm in global deepwater frontier basins in advance through bidding at a low cost and adopt the “dual exploration model” after making large-scale discoveries;second, enter new blocks of emerging hot basins in the world through farm-in and other ways, to find large oil and gas fields quickly;third, cooperate with national oil companies of the resource host countries in the form of joint research and actively participate exploration of deep onshore formations of petroliferous basins;fourth, track tight/shale oil and gas cooperation opportunities in a few countries such as Saudi Arabia and Russia, and take advantage of mature domestic theories and technologies to farm in at an appropriate time.展开更多
Exploration budgets for primary battery metals-nickel,lithium and cobalt-tempered in 2024 at$1.697 billion,reflecting a marginal 0.4%decline and a virtually flat annual total,compared to$1.704 billion in 2023.Below is...Exploration budgets for primary battery metals-nickel,lithium and cobalt-tempered in 2024 at$1.697 billion,reflecting a marginal 0.4%decline and a virtually flat annual total,compared to$1.704 billion in 2023.Below is an introduction to the 2024 global exploration trends and prospects for lithium,cobalt,and nickel battery metals.展开更多
The Zhujiang(Pearl)River Mouth Basin(PRMB)is located in the northern part of the South China Sea,and it is one of China’s three major offshore hydrocarbon-rich basins,playing an indispensable role in meeting the coun...The Zhujiang(Pearl)River Mouth Basin(PRMB)is located in the northern part of the South China Sea,and it is one of China’s three major offshore hydrocarbon-rich basins,playing an indispensable role in meeting the country’s energy needs.Exploration for oil in the PRMB started early and has achieved remarkable results in some sags,but many sags have yet to yield significant discoveries,necessitating the search for new favorable exploration areas.The aim of this study is to analyze the deep structural characteristics of various sags in the PRMB and predict favorable exploration areas,providing corresponding support for the next strategic breakthrough in oil exploration.Some studies indicate a certain relationship between the Moho depth and crustal thickness and the occurrence of oil.In this paper,based on satellite altimetry gravity anomaly data,we utilize a Moho depth inversion method based on variable residual crustal density to obtain the Moho depth in the PRMB,from which the crustal thickness and crustal stretching factor of the basin are calculated.The results show that the Moho depth in the PRMB ranges from 10 km to 37 km,the crustal thickness ranges from 7 km to 35 km,and the crustal stretching factor ranges from 0.9 to 3.0.Finally,we propose a comprehensive evaluation scheme for oil resoureces based on the CRiteria Importance Through Intercriteria Correlation(CRITIC)method,which comprehensively evaluates multiple factors,such as the Cenozoic sedimentary filling scale,Cenozoic thickness,Moho depth,crustal thickness,and crustal stretching factor,and provides evaluation criteria for identifying hydrocarbon-rich sags.According to this evaluation scheme,the exploration potential is relatively high in the Liwan Sag,Jinghai Sag,Heshan Sag,and Jieyang Sag,which are favorable exploration areas.展开更多
The well deployment in the Ordovician Yingshan Formation in the Gucheng area of the Tarim Basin mainly focuses on the inner gentle slope in the western part of the study area,which results in a low drilling success ra...The well deployment in the Ordovician Yingshan Formation in the Gucheng area of the Tarim Basin mainly focuses on the inner gentle slope in the western part of the study area,which results in a low drilling success rate.To address this issue,this study focused on reconstructing sedimentary models and the adjustment strategies for oil and gas exploration.The carbonate sedimentary model of the Yingshan Formation was re-evaluated using the data of seismic interpretation,core observations,thin-section analyses,carbon isotopic composition,well logging,detrital zircon U-Pb dating,and carbonate mineral U-Pb dating.Then,the favorable sedimentary facies belts were delineated,and updated prospective exploration targets were proposed.The results demonstrate that the sedimentary model of the Yingshan Formation in the Gucheng area is characterized as a rimmed platform system,exhibiting an orderly west-to-east sedimentary sequence transition from restricted/open platform environments through the platform margin and slope settings,ultimately grading into basinal deposits.The platform margin,distinguished by thick successions of grain shoals overlain by interlayered karst zones,is the most favorable distribution area for large-scale reservoirs.Guided by this revised sedimentary model,Well Gutan-1 was successfully drilled within the outer platform margin,encountering over 90%high-energy grain shoal facies with well-developed porous and fractured-vuggy reservoirs,and achieving industrial oil and gas flow.It is confirmed that the platform margin is the priority area for oil and gas exploration in the Ordovician System of the Gucheng area,thereby effectively ending the prolonged exploration stagnation in the Yingshan Formation of the Gucheng area.展开更多
The shale gas resources in China have great potential and the geological resources of shale gas is over 100×10^(12)m^(3),which includes about 20×10^(12)m^(3) of recoverable resources.Organic-rich shales can ...The shale gas resources in China have great potential and the geological resources of shale gas is over 100×10^(12)m^(3),which includes about 20×10^(12)m^(3) of recoverable resources.Organic-rich shales can be divided into three types according to their sedimentary environments,namely marine,marine-continental transitional,and continental shales,which are distributed in 13 stratigraphic systems from the Mesoproterozoic to the Cenozoic.The Sichuan Basin and its surrounding areas have the highest geological resources of shale gas,and the commercial development of shale gas has been achieved in the Upper Ordovician Wufeng Formation-Lower Silurian Longmaxi Formation in these areas,with a shale gas production of up to 20×10^(9)m^(3) in 2020.China has seen rapid shale gas exploration and development over the last five years,successively achieving breakthroughs and important findings in many areas and strata.The details are as follows.(1)Large-scale development of middle-shallow shale gas(burial depth:less than 3500 m)has been realized,with the productivity having rapidly increased;(2)breakthroughs have been constantly made in the development of deep shale gas(burial depth:3500-4500 m),and the ultradeep shale gas(burial depth:greater than 4500 m)is under testing;(3)breakthroughs have been made in the development of normal-pressure shale gas,and the assessment of the shale gas in complex tectonic areas is being accelerated;(4)shale gas has been frequently discovered in new areas and new strata,exhibiting a great prospect.Based on the exploration and development practice,three aspects of consensus have been gradually reached on the research progress in the geological theories of shale gas achieved in China.(1)in terms of deep-water fine-grained sediments,organic-rich shales are the base for the formation of shale gas;(2)in terms of high-quality reservoirs,the development of micro-nano organic matter-hosted pores serves as the core of shale gas accumulation;(3)in terms of preservation conditions,weak structural transformation,a moderate degree of thermal evolution,and a high pressure coefficient are the key to shale gas enrichment.As a type of important low-carbon fossil energy,shale gas will play an increasingly important role in achieving the strategic goals of peak carbon dioxide emissions and carbon neutrality.Based on the in-depth study of shale gas geological conditions and current exploration progress,three important directions for shale gas exploration in China in the next five years are put forward.展开更多
One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific object...One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific objectives,measurement targets,and measurement requirements for the proposed Gas and Ion Analyzer(GIA).The GIA is designed for in-situ mass spectrometry of neutral gases and low-energy ions,such as hydrogen,carbon,and oxygen,in the vicinity of 311P.Ion sampling techniques are essential for the GIA's Time-of-Flight(TOF)mass analysis capabilities.In this paper,we present an enhanced ion sampling technique through the development of an ion attraction model and an ion source model.The ion attraction model demonstrates that adjusting attraction grid voltage can enhance the detection efficiency of low-energy ions and mitigate the repulsive force of ions during sampling,which is influenced by the satellite's surface positive charging.The ion source model simulates the processes of gas ionization and ion multiplication.Simulation results indicate that the GIA can achieve a lower pressure limit below 10-13Pa and possess a dynamic range exceeding 10~9.These performances ensure the generation of ions with stable and consistent current,which is crucial for high-resolution and broad dynamic range mass spectrometer analysis.Preliminary testing experiments have verified GIA's capability to detect gas compositions such as H2O and N2.In-situ measurements near 311P using GIA are expected to significantly contribute to our understanding of asteroid activity mechanisms,the evolution of the atmospheric and ionized environments of main-belt comets,the interactions with solar wind,and the origin of Earth's water.展开更多
The ultra-deep(deeper than 8000 m)petroleum in the platform-basin zones of the Tarim Basin has been found mainly in the Lower Paleozoic reservoirs located to the east of the strike-slip fault F5 in the north depressio...The ultra-deep(deeper than 8000 m)petroleum in the platform-basin zones of the Tarim Basin has been found mainly in the Lower Paleozoic reservoirs located to the east of the strike-slip fault F5 in the north depression.However,the source and exploration potential of the ultra-deep petroleum in the Cambrian on the west of F5 are still unclear.Through the analysis of lithofacies and biomarkers,it is revealed that there are at least three kinds of isochronous source rocks(SRs)in the Cambrian Newfoundland Series in Tarim Basin,which were deposited in three sedimentary environments,i.e.sulfide slope,deep-water shelf and restricted bay.In 2024,Well XT-1 in the western part of northern Tarim Basin has yielded a high production of condensate from the Cambrian.In the produced oil,entire aryl-isoprenoid alkane biomarkers were detected,but triaromatic dinosterane was absent.This finding is well consistent with the geochemical characteristics of the Newfoundland sulfidized slope SRs represented by those in wells LT-1 and QT-1,suggesting that the Newfoundland SRs are the main source of the Cambrian petroleum discovered in Well XT-1.Cambrian crude oil of Well XT-1 also presents the predominance of C29 steranes and is rich in long-chain tricyclic terpanes(up to C39),which can be the indicators for effectively distinguishing lithofacies such as siliceous mudstone and carbonate rock.Combined with the analysis of hydrocarbon accumulation in respect of conduction systems including thrust fault and strike-slip fault,it is found that the area to the west of F5 is possible to receive effective supply of hydrocarbons from the Cambrian Newfoundland SRs in Manxi hydrocarbon-generation center.This finding suggests that the area to the west of F5 will be a new target of exploration in the Cambrian ultra-deep structural-lithologic reservoirs in the Tarim Basin,in addition to the Cambrian ultra-deep platform-margin facies-controlled reservoirs in the eastern part of the basin.展开更多
In multi-component oil and gas exploration using ocean bottom nodes,converted wave data is rich in lithological and fracture information.One of the urgent problems to be solved is how to construct an accurate shear wa...In multi-component oil and gas exploration using ocean bottom nodes,converted wave data is rich in lithological and fracture information.One of the urgent problems to be solved is how to construct an accurate shear wave velocity model of the shallow sea bottom by leveraging the seismic wave information at the fluid-solid interface in the ocean,and improve the lateral resolution of marine converted wave data.Given that the dispersion characteristics of surface waves are sensitive to the S-wave velocity of subsurface media,and that Scholte surface waves,which propagate at the interface between liquid and solid media,exist in the data of marine oil and gas exploration,this paper proposes a Scholte wave inversion and modeling method based on oil and gas exploration using ocean bottom nodes.By using the method for calculating the Scholte wave dispersion spectrum based on the Bessel kernel function,the accuracy of dispersion spectrum analysis is improved,and more accurate dispersion curves are picked up.Through the adaptive weighted least squares Scholte wave dispersion inversion algorithm,the Scholte wave dispersion equation for liquid-solid media is solved,and the shear wave velocity model of the shallow sea bottom is calculated.Theoretical tests and applications of realdata have proven that this method can significantly improve the lateral resolution of converted wave data,provide high-quality data for subsequent inversion of marine multi-component oil and gas exploration data and reservoir reflection information,and contribute to the development of marine oil and gas exploration technology.展开更多
The coal-bearing source rocks in the Jurassic Shuixigou Group have received widespread attention as the primary source rocks in the Turpan-Hami Basin of China,but the hydrocarbon generation potential and process of th...The coal-bearing source rocks in the Jurassic Shuixigou Group have received widespread attention as the primary source rocks in the Turpan-Hami Basin of China,but the hydrocarbon generation potential and process of the mudstone in the Shuixigou Group,especially the mudstone at the top of the Sangonghe Formation,are unclear.Taking the source rocks of the Xishanyao Formation and the Sangonghe Formation as objectives,this study conducted rock pyrolysis and gold tube simulation experiment to investigate their hydrocarbon generation characteristics and differences.Our results indicate that the source rocks of the Xishanyao Formation include mudstone,carbonaceous mudstone and coal,and the quality of the source rocks is highly heterogeneous;the source rocks of the Sangonghe Formation are mainly composed of mudstone,and it is a good gas source rock.Simulation experiments found that the activation energy required for the generation of gaseous hydrocarbons by the mudstone of the Sangonghe Formation is lower than that by the mudstone of the Xishanyao Formation.The hydrocarbon generation process can be divided into three stages for both formations,but the gas generation potential of the Xishanyao Formation mudstone is higher than that of the Sangonghe Formation mudstone.A large amount of hydrocarbon was generated by the mudstone of the Xishanyao Formation when entering late thermal evolution,of which methane is dominant,mainly from the demethylation reaction of mature kerogen.On the other hand,a large amount of hydrocarbon was generated by the mudstone of the Sangonghe Formation in the early stage of thermal evolution,of which light hydrocarbon and wet gas are dominant,mainly from the early cracking stage of kerogen.This difference may be attributed to the structure of kerogen.The mudstone of the Xishanyao Formation is conducive to the formation of highly mature dry gas reservoirs,while the mudstone of the Sangonghe Formation is conducive to the formation of low maturity condensate gas and volatile oil reservoirs.The research result provides a scientific basis for the comparison of oil and gas sources and the evaluation of oil and gas resources in the Turpan-Hami Basin.展开更多
Three cases of structural-stratigraphic accumulations in the foredeep zone of the Oriente Basin have been analyzed.The target reservoirs are U and M1 sections of Napo Fm.in the Basin.Seismic amplitude maps are used fo...Three cases of structural-stratigraphic accumulations in the foredeep zone of the Oriente Basin have been analyzed.The target reservoirs are U and M1 sections of Napo Fm.in the Basin.Seismic amplitude maps are used for sand distribution pattern,and wells interpretation and correlations are applied for fluid distribution and reservoir continuity.These cases show that their oil distribution areas are significantly larger than their structure closures and thus should be structural-stratigraphic traps.But only in one case,lateral stratigraphic/lithological seals can be clearly observed.In the other two,the lateral seals are apparently discontinuous and cannot provide a complete barrier at the up-dip of the structures.Possible factors for the formation of those untypical structural-stratigraphic accumulations are studied,such as formation water flow and water head variations,basin and field structure evolution patterns,oil generation and charging history etc.An integrated mechanism is proposed in this study,where three factors may have acted together.1)Slow long distance oil migration in LU and M1 reservoirs,due to their lateral discontinuity in the foredeep of the basin.This is supported by the distal estuarine and prodelta depositional environment suggested by previous sedimentological studies.2)Ongoing secondary oil migration from south to north,caused by southward plunging and destruction of proto accumulations in the southern and middle part of the basin.This structure deformation is in turn caused by differential subsidence between the southern and northern part of the basin.3)Additional oil supplied from the southern kitchen.The southern source kitchen is still in the oil window and providing pulses of oil charge since the Oligocene.If this mechanism is valid,it would imply that in the southern and northern transition zone of the basin,similar untypical traps should also exist.The area of southern extension of the two untypical accumulation is over 50 km2,while within the basin,the transition zone of differential basin subsidence with distal and thus discontinuous LU and M1 reservoirs covers an area over 2000 km2.These findings suggest a new and potentially extensive play concept with significant exploration potential in the Oriente Basin.展开更多
The Cambrian platform margin in the Tarim Basin boasts favorable source-reservoir-cap assemblages,making it a significant target for hydrocarbon exploration in ultra-to extra-deep facies-controlled for-mations.Of the ...The Cambrian platform margin in the Tarim Basin boasts favorable source-reservoir-cap assemblages,making it a significant target for hydrocarbon exploration in ultra-to extra-deep facies-controlled for-mations.Of the three major basins in western China,Tarim is the only basin with large-scale platform margin where no exploration breakthrough has been achieved yet.This study determines the vertical and lateral differential evolution of the platform margin(in the Manxi area hereafter referred to as the Cambrian Manxi platform margin)through fine-scale sequence stratigraphic division and a segmented analysis.The platform margin can be divided into the Yuqi,Tahe,Shunbei,and Gucheng segments,from north to south,based on the development of different ancient landforms and the evolutionary process of the platform.The Yuqi and Shunbei segments exhibit relatively low-elevation ancient landforms.Both segments were in a submarine buildup stage during the Early Cambrian,resulting in overall limited scales of their reservoirs.The Gucheng segment features the highest-elevation ancient landforms and accordingly limited accommodation spaces.As a result,the rapid lateral migration of high-energy facies zones leads to the development of large-scale reservoirs with only limited thicknesses.In contrast,the Tahe segment,exhibiting comparatively high-elevation ancient landforms,is identified as the most favorable segment for the formation of large-scale reservoirs.The cap rocks of the platform margin are dominated by back-reef dolomitic flats and tight carbonate rocks formed in transgressive periods.A comprehensive evaluation of source rocks,reservoirs,and cap rocks indicates that the Tahe segment boasts the optimal hydrocarbon accumulation conditions along the platform margin.In this segment,the Shayilike Formation transgressive deposits and the high-energy mound-shoal complexes along the platform margin of the Wusonggeer Formation constitute the optimal reservoir-cap rock assemblage,establishing this segment as the most promising target for hydrocarbon exploration in the platform margin.展开更多
By integrating core observations,logging data and seismic interpretation,this study takes the massive Cretaceous carbonates in the M block of the Santos Basin,Brazil,as an example to establish the sequence filling pat...By integrating core observations,logging data and seismic interpretation,this study takes the massive Cretaceous carbonates in the M block of the Santos Basin,Brazil,as an example to establish the sequence filling pattern of fault-bounded isolated platforms in rift lake basins,reveal the control mechanisms of shoal-body development and reservoir formation,and reconstruct the evolutionary history of lithofacies paleogeography.The following results are obtained.(1)Three tertiary sequences(SQ1-SQ3)are identified in the Lower Cretaceous Itapema-Barra Velha of the M block.During the depositional period of SQ1,the rift basement faults controlled the stratigraphic distribution pattern of thick on both sides and thin in the middle.The strata overlapped to uplift in the early stage.During the depositional period of SQ2-SQ3,the synsedimentary faults controlled the paleogeomorphic reworking process with subsidence in the northwest and uplifting in the northeast,accompanied with the relative fall of lake level.(2)The Lower Cretaceous in the M block was deposited in a littoral-shallow lake,with the lithofacies paleogeographic pattern transiting from the inner clastic shoals and outer shelly shoals in SQ1 to the alternation of mounds and shoals in SQ2-SQ3.(3)Under the joint control of relative lake-level fluctuation,synsedimentary faults and volcanic activity,the shelly shoals in SQ1 tend to accumulated vertically in the raised area,and the mound-shoal complex in SQ2-SQ3 tends to migrate laterally towards the slope-break belt due to the reduction of accommodation space.(4)The evolution pattern of high-energy mounds and shoals,which were vertically accumulated in the early stage and laterally migrated in the later stage,controlled the transformation of high-quality reservoirs from“centralized”to“ring shaped”distribution.The research findings clarify the sedimentary patterns of mounds and shoals and the distribution of favorable reservoirs in the fault-controlled lacustrine isolated platform,providing support for the deepwater hydrocarbon exploration in the subsalt carbonate rocks in the Santos Basin.展开更多
Whether clay-rich shale reservoirs with low-medium maturity can serve as primary exploration targets remains a focal point of debate in the academic community.Clarifying the exploration potential of clayrich shale res...Whether clay-rich shale reservoirs with low-medium maturity can serve as primary exploration targets remains a focal point of debate in the academic community.Clarifying the exploration potential of clayrich shale reservoirs is crucial for the future exploration and development of lacustrine shale.The Triassic Yanchang Formation in the Ordos Basin has been one of most productive lacustrine shale oil systems in China,with substantial oil production capacity already established.While the primary productive layers are currently fine-grained siltstone interbeds,however,it remains a highly debated issue whether the volumetrically more significant clay-rich reservoirs can become viable exploration targets in the near future.To address this issue,we examined the exploration potential of different lithofacies assemblages in Member 7(Mbr 7)of the Triassic Yanchang Formation,using a borehole in the Tongchuan area of the southern Ordos Basin as an example.We identified favorable exploration targets and assessed whether clay-rich reservoirs formed predominantly-freshwater conditions can become viable exploration targets.The results indicate the presence of six lithofacies in clay-rich reservoirs of Mbr 7 of the Yanchang Formation,with two main lithofacies assemblages:laminated organic-rich shale and massive mudstone.From the perspective of sandstone distribution,the sandstone interlayers within laminated organic-rich shale are primarily formed by gravity(hyperpycnal)flows,while sandstones deposited in delta front environments are typically associated with massive mudstone.Laminated organic-rich shale deposition occurred in an anoxic,deep-water environment characterized by high primary productivity,whereas massive mudstone formed in environments with high sedimentation rates and substantial terrigenous debris influx.Currently,the exploration potential of sandstone interlayers exceeds that of clay-rich reservoirs,with the greatest potential observed in the sandstone interlayers associated with laminated organic-rich shale formed by gravity(hyperpycnal)flows.Comparative analysis reveals that clay-rich reservoirs with low to medium maturity present great challenges for exploitation,making interlayer-type reservoirs the main focus of exploration at this stage.Nevertheless,clay-rich reservoirs in closed systems with high thermal maturity and organic matter content also hold considerable potential.展开更多
Mineral exploration under exotic overburden has been a great challenge in exploration geochemistry.Gas geochemical measurement is a potential method for mineral exploration due to the characteristics of strong penetra...Mineral exploration under exotic overburden has been a great challenge in exploration geochemistry.Gas geochemical measurement is a potential method for mineral exploration due to the characteristics of strong penetrability and vertical migration.The previous rapid gas analyzer cannot determine low concentrations of soil gases because of inadequate sensitivity,therefore,it is necessary to develop a more sensitive analytical technique.In this paper,the pilot studies on CO_(2) and SO_(2) geochemical measurements were performed at the Zhuxi W-(Cu)deposit,Jiapigou gold ore-concentrated area,and Tukuzbay gold deposit.This study employed rapid gas analyzer based on Infrared Absorption Spectroscopy and Electrochemical Analysis,which can detect low concentrations of CO_(2) and SO_(2) and greatly improve the reliability of test data.The results show that CO_(2) and SO_(2) show clear anomalies over deeply concealed ore bodies and faults,demonstrating that CO_(2) and SO_(2) anomalies can reveal indicative information about concealed mineralization and faults.Moreover,CO_(2) and SO_(2) anomalies can identify mineralization information exceeding 1,000 m in depth,suggesting that this method has large detection depth.Therefore,CO_(2) and SO_(2) geochemical measurement method is a feasible tool to discern deeply concealed mineralization and faults,and can provide a new idea in prospecting for concealed ore deposits in covered areas.展开更多
The 128.6-m-thick,shale-dominated Klimoli,Wulalike and Lashizhong formations exposed at the Hatuke Creek Section in the Zhuozishan area of Inner Monglia,North China,have been investigated for conodonts.Detailed strati...The 128.6-m-thick,shale-dominated Klimoli,Wulalike and Lashizhong formations exposed at the Hatuke Creek Section in the Zhuozishan area of Inner Monglia,North China,have been investigated for conodonts.Detailed stratigraphical collections of conodonts preserved on bedding planes from graptolitic shales,supplemented by additional discrete conodonts acid-leached from limestones,enable a refinement of the conodont biostratigraphic scheme at this section.Four successive conodont biozones,ranging in age from mid Darriwilian to late Sandbian(Stage slices Dw2–Sa2),are identified:the Dzikodus tablepointensis Biozone,the Eoplacognathus suecicus Biozone,the Pygodus serra Biozone,and the Pygodus anserinus Biozone,in ascending order.New sub-biozones,based on morphotypes of the biozonal index species,are proposed for the Pygodus serra and Pygodus anserinus biozones,providing alternatives when the traditional sub-biozones are unrecognizable.The biozonation is clearly correlated with the coeval Baltoscandian,South American and South China reference standard successions.The diverse preservation states of conodont bedding plane assemblages suggest that the alteration of conodonts in graptolitic shales represents a diagenetic process,challenging the prevailing hypothesis of pre-diagenetic dissolution.This study highlights the crucial role of previously overlooked conodont bedding plane assemblages in correlating Ordovician slope/basin facies shales,which holds great potential for marine shale gas exploration.展开更多
Coal-measure gas is a primary target with significant potential for the exploration of unconventional hydrocarbon resources.However,the spatiotemporal distribution and combination patterns of multi-type coal-measure g...Coal-measure gas is a primary target with significant potential for the exploration of unconventional hydrocarbon resources.However,the spatiotemporal distribution and combination patterns of multi-type coal-measure gases are yet to be clarified,directly impeding the sweet spot evaluation and exploration deployment of coal-measure gas.This study discussed the characteristics and distribution patterns of coal-measure gases in the Daniudi gas field in northeastern Ordos Basin,China,with abundant drilling data.The results indicate that the coal seams variably thin upward and are mainly seen in the first and second members of the Taiyuan Formation(also referred to as the Tai 1 and Tai 2 members,respectively)and the first member of the Shanxi Formation(Shan 1 Member).Nos.8,5 and 3 coal seams are laterally continuous,and significantly thicker in its southern part compared to the northern part.Moreover,carbonaceous mudstones and shales are better developed in the southern part,where limestones are only observed in the Tai 1 Member.Based on the main lithological types,we identified three lithologic roofs of coal seams,that is,limestone,mudstone,and sandstone,which determine the spatiotemporal distribution of coal-measure gases.Besides bauxite gas in the Benxi Formation,the coal-measure gases include tight-sand gas,coalbed methane(CBM),coal-measure shale gas,and tight-limestone gas,with CBM typically associated with coal-measure shale gas.The combinations of different types of coal-measure gas vary across different layers and regions.Tight-sand gas is well-developed in areas where tight sandstones are in contact with coal-measures.From the Taiyuan to the Shanxi formations,CBM gradually transitions into a combination of CBM and coal-measure shale gas,and coal-measure shale gas.Nos.8 and 5 coal seams in low-lying areas exhibit favorable gas-bearing properties due to their large thickness and favorable roof lithologies,serving as prospective play fairways.Mudstone and limestone roofs are more conducive to achieving good gas-bearing properties.The direct contact between sandstones and coal seams tends to result in the formation of tight-sand gas and a reduced gas content of CBM.While focusing on single types of gas reservoirs such as CBM and tight-sand gas,it is essential to consider the concurrent exploration of various coal-measure gas combinations to discover more additional gas resources and guide exploration deployment.展开更多
The giant Pulang porphyry copper deposit,located in the southern Yidun arc segment of southeastern Tibetan Plateau,represents one of the region’s largest mineral systems.This study employs numerical simulation to unr...The giant Pulang porphyry copper deposit,located in the southern Yidun arc segment of southeastern Tibetan Plateau,represents one of the region’s largest mineral systems.This study employs numerical simulation to unravel its metallogenic processes.By integrating field-based geological observations with mineralogical and geochemical data,we developed a coupled model encompassing five key stages of ore formation.The simulation successfully reproduced thermal anomalies and accurately predicted the spatial distribution of mineralization zones at Pulang.Coupling dynamic modeling results with chalcopyrite precipitation rates and average Cu grades enabled quantitative estimation of deposit formation duration(0.99–1.22 Ma).Compared with conventional geochronological approaches,this process-constrained modeling framework provides unprecedented insights into the thermodynamic mechanisms controlling porphyry copper system evolution,offering valuable implications for regional exploration strategies.展开更多
Zirconium,prized for its exceptional corrosion resistance,high melting point,and unique nuclear properties,plays a critical role in multiple industrial sectors globally.Zirconium deposits are categorized into endogene...Zirconium,prized for its exceptional corrosion resistance,high melting point,and unique nuclear properties,plays a critical role in multiple industrial sectors globally.Zirconium deposits are categorized into endogenetic and exogenetic types in China.Endogenetic deposits-including alkaline rock-,alkaline granite-,and pegmatite-type mineralizations-predominantly occur along the Tarim Craton’s northern margin,the North China Craton,the southern Greater Khingan metallogenic belt,and the Yangtze Craton’s western margin.Exogenetic deposits,comprising clastic sedimentary,weathering crust,and fragmentation types,are concentrated in South China’s coastal zones.Endogenetic mineralization formed during Permian-Cretaceous magmatic-hydrothermal events linked to evolved alkaline granitic systems,while exogenetic deposits developed in Quaternary periods through weathering of zirconium-rich protoliths.However,economic extraction of endogenetic deposits remains constrained by rare earth element(REE)associations and radioactive complexities.Currently,China’s most economically significant reserves derive from clastic sedimentary systems,particularly coastal placer deposits.This study systematically synthesizes the spatial distribution and metallogenic mechanisms of Chinese zirconium deposits,offering strategic insights for resource exploration and sustainable utilization.展开更多
China has carried out four unmanned missions to the Moon since it launched Chang’E-1,the first lunar orbiter in 2007.With the implementation of the Chang’E-5 mission this year,the three phases of the lunar explorati...China has carried out four unmanned missions to the Moon since it launched Chang’E-1,the first lunar orbiter in 2007.With the implementation of the Chang’E-5 mission this year,the three phases of the lunar exploration program,namely orbiting,landing and returning,have been completed.In the plan of follow-up unmanned lunar exploration missions,it is planned to establish an experimental lunar research station at the lunar south pole by 2030 through the implementation of several missions,laying a foundation for the establishment of practical lunar research station in the future.China successfully launched its first Mars probe on 23 July 2020,followed in future by an asteroid mission,second Mars mission,and a mission to explore Jupiter and its moons.展开更多
基金co-funded by the National Natural Science Foundation of China(42372160,42072172)。
文摘The Neogene Shawan Formation in the Chepaizi Uplift of the Junggar Basin(NW China)has obtained high oil flow,demonstrating a good potential for oil and gas exploration.The multi-source hydrocarbon generation background and strong tectonic activity have led to the simultaneous production of heavy oil and light oil from multi-layer in the area,which makes it very difficult to identify oil origins,presently,the hot debate on the oil origins needs to be clarified.In this paper,due to the selective consumption of different types of compounds in crude oils by severe and intense biodegradation,the commonly used oilsource correlation tools are ineffective or may produce misleading results,this study adopted a biomarker recovery method based on the principle of mass conservation that uses the sum of the mass of the residual biomarkers and their corresponding biodegradation products to obtain the mass of the original biomarkers,improving the reliability of oil origins determination.Based on the nature and occurrence of crude oils,the investigated oils are subdivided into three types,Group A,Group B and Group C.Group A,light oils occurred mainly in lower structure Neogene Shawan Formation in the western Chepaizi Uplift,while Group B,heavy oils occurred mainly in higher structure Neogene Shawan Formation in the western Chepaizi Uplift.The two types of crude oils may come from the mixed source of Jurassic Badaowan Formation source rocks(J_(1)b)and Paleogene Anjihaihe Formation source rocks(E_(2-3)a)in the Sikeshu Sag,and Jurassic Badaowan Formation source rocks(J_(1)b)are the main source of crude oils.Group C,heavy oils occurred mainly in Neogene Shawan Formation in the eastern Chepaizi Uplift,showing good correlation with the Permian(P_(1)f and P_(2)w)source rocks in the Shawan Sag.At the same time,by combining stable carbon isotope and parameters related to triaromatic steroids,the accuracy of the oilsource correlation results by biomarker recovery method was further verified.
基金Petro China Scientific Research and Technology Development Project(2021DJ3101,2022-FW-041)。
文摘The global exploration investment, new oil and gas discoveries, exploration business adjustment strategies of oil companies in 2021, and future favorable exploration domains are systematically analyzed using commercial databases such as IHS and public information of oil companies. It has been found that the world oil and gas exploration situation in 2021 has continued the downturn since the outbreak of COVID-19. The investment and drilling workload decreased slightly, but the success rate of exploration wells, especially deepwater exploration wells, increased significantly, and the newly discovered reserves increased slightly compared with last year. Deep waters of the passive continental margin basins are still the leading sites for discovering conventional large and medium-sized oil and gas fields. The conventional oil and gas exploration in deep formations of onshore petroliferous basins has been keeping a good state, with tight/shale oil and gas discoveries made in Saudi Arabia, Russia, and other countries. While strengthening the exploration and development of local resources, national, international, and independent oil companies have been focusing on major overseas frontiers using their advantages, including risk exploration in deep waters and natural gas. Future favorable exploration directions in the three major frontiers, the global deep waters, deep onshore formations, and unconventional resources, have been clarified. Four suggestions are put forward for the global exploration business of Chinese oil companies: first, a farm in global deepwater frontier basins in advance through bidding at a low cost and adopt the “dual exploration model” after making large-scale discoveries;second, enter new blocks of emerging hot basins in the world through farm-in and other ways, to find large oil and gas fields quickly;third, cooperate with national oil companies of the resource host countries in the form of joint research and actively participate exploration of deep onshore formations of petroliferous basins;fourth, track tight/shale oil and gas cooperation opportunities in a few countries such as Saudi Arabia and Russia, and take advantage of mature domestic theories and technologies to farm in at an appropriate time.
文摘Exploration budgets for primary battery metals-nickel,lithium and cobalt-tempered in 2024 at$1.697 billion,reflecting a marginal 0.4%decline and a virtually flat annual total,compared to$1.704 billion in 2023.Below is an introduction to the 2024 global exploration trends and prospects for lithium,cobalt,and nickel battery metals.
基金The Fundamental Research Funds for the Central Universities,CHD,under contract No.300102264106the Shaanxi Natural Science Basic Research Program under contract No.2025JC-YBQN-370the Scientific and Technological Project of CNOOC Research Institute Co.,Ltd.under contract No.CCL2021RCPS0167KQN.
文摘The Zhujiang(Pearl)River Mouth Basin(PRMB)is located in the northern part of the South China Sea,and it is one of China’s three major offshore hydrocarbon-rich basins,playing an indispensable role in meeting the country’s energy needs.Exploration for oil in the PRMB started early and has achieved remarkable results in some sags,but many sags have yet to yield significant discoveries,necessitating the search for new favorable exploration areas.The aim of this study is to analyze the deep structural characteristics of various sags in the PRMB and predict favorable exploration areas,providing corresponding support for the next strategic breakthrough in oil exploration.Some studies indicate a certain relationship between the Moho depth and crustal thickness and the occurrence of oil.In this paper,based on satellite altimetry gravity anomaly data,we utilize a Moho depth inversion method based on variable residual crustal density to obtain the Moho depth in the PRMB,from which the crustal thickness and crustal stretching factor of the basin are calculated.The results show that the Moho depth in the PRMB ranges from 10 km to 37 km,the crustal thickness ranges from 7 km to 35 km,and the crustal stretching factor ranges from 0.9 to 3.0.Finally,we propose a comprehensive evaluation scheme for oil resoureces based on the CRiteria Importance Through Intercriteria Correlation(CRITIC)method,which comprehensively evaluates multiple factors,such as the Cenozoic sedimentary filling scale,Cenozoic thickness,Moho depth,crustal thickness,and crustal stretching factor,and provides evaluation criteria for identifying hydrocarbon-rich sags.According to this evaluation scheme,the exploration potential is relatively high in the Liwan Sag,Jinghai Sag,Heshan Sag,and Jieyang Sag,which are favorable exploration areas.
基金Supported by the National Natural Science Foundation of China General Program(42272181)CNPC-Southwest Petroleum University Innovation Consortium Program(2020CX010301).
文摘The well deployment in the Ordovician Yingshan Formation in the Gucheng area of the Tarim Basin mainly focuses on the inner gentle slope in the western part of the study area,which results in a low drilling success rate.To address this issue,this study focused on reconstructing sedimentary models and the adjustment strategies for oil and gas exploration.The carbonate sedimentary model of the Yingshan Formation was re-evaluated using the data of seismic interpretation,core observations,thin-section analyses,carbon isotopic composition,well logging,detrital zircon U-Pb dating,and carbonate mineral U-Pb dating.Then,the favorable sedimentary facies belts were delineated,and updated prospective exploration targets were proposed.The results demonstrate that the sedimentary model of the Yingshan Formation in the Gucheng area is characterized as a rimmed platform system,exhibiting an orderly west-to-east sedimentary sequence transition from restricted/open platform environments through the platform margin and slope settings,ultimately grading into basinal deposits.The platform margin,distinguished by thick successions of grain shoals overlain by interlayered karst zones,is the most favorable distribution area for large-scale reservoirs.Guided by this revised sedimentary model,Well Gutan-1 was successfully drilled within the outer platform margin,encountering over 90%high-energy grain shoal facies with well-developed porous and fractured-vuggy reservoirs,and achieving industrial oil and gas flow.It is confirmed that the platform margin is the priority area for oil and gas exploration in the Ordovician System of the Gucheng area,thereby effectively ending the prolonged exploration stagnation in the Yingshan Formation of the Gucheng area.
基金supported by a project of shale gas in Southern China(DD20190561)initiated by the China Geological Surveythe project for High-level Innovative Talents in Science and Technology,Ministry of Natural Resources(12110600000018003918)。
文摘The shale gas resources in China have great potential and the geological resources of shale gas is over 100×10^(12)m^(3),which includes about 20×10^(12)m^(3) of recoverable resources.Organic-rich shales can be divided into three types according to their sedimentary environments,namely marine,marine-continental transitional,and continental shales,which are distributed in 13 stratigraphic systems from the Mesoproterozoic to the Cenozoic.The Sichuan Basin and its surrounding areas have the highest geological resources of shale gas,and the commercial development of shale gas has been achieved in the Upper Ordovician Wufeng Formation-Lower Silurian Longmaxi Formation in these areas,with a shale gas production of up to 20×10^(9)m^(3) in 2020.China has seen rapid shale gas exploration and development over the last five years,successively achieving breakthroughs and important findings in many areas and strata.The details are as follows.(1)Large-scale development of middle-shallow shale gas(burial depth:less than 3500 m)has been realized,with the productivity having rapidly increased;(2)breakthroughs have been constantly made in the development of deep shale gas(burial depth:3500-4500 m),and the ultradeep shale gas(burial depth:greater than 4500 m)is under testing;(3)breakthroughs have been made in the development of normal-pressure shale gas,and the assessment of the shale gas in complex tectonic areas is being accelerated;(4)shale gas has been frequently discovered in new areas and new strata,exhibiting a great prospect.Based on the exploration and development practice,three aspects of consensus have been gradually reached on the research progress in the geological theories of shale gas achieved in China.(1)in terms of deep-water fine-grained sediments,organic-rich shales are the base for the formation of shale gas;(2)in terms of high-quality reservoirs,the development of micro-nano organic matter-hosted pores serves as the core of shale gas accumulation;(3)in terms of preservation conditions,weak structural transformation,a moderate degree of thermal evolution,and a high pressure coefficient are the key to shale gas enrichment.As a type of important low-carbon fossil energy,shale gas will play an increasingly important role in achieving the strategic goals of peak carbon dioxide emissions and carbon neutrality.Based on the in-depth study of shale gas geological conditions and current exploration progress,three important directions for shale gas exploration in China in the next five years are put forward.
基金Supported by the National Natural Science Foundation of China(42474239,41204128)China National Space Administration(Pre-research project on Civil Aerospace Technologies No.D010301)Strategic Priority Research Program of the Chinese Academy of Sciences(XDA17010303)。
文摘One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific objectives,measurement targets,and measurement requirements for the proposed Gas and Ion Analyzer(GIA).The GIA is designed for in-situ mass spectrometry of neutral gases and low-energy ions,such as hydrogen,carbon,and oxygen,in the vicinity of 311P.Ion sampling techniques are essential for the GIA's Time-of-Flight(TOF)mass analysis capabilities.In this paper,we present an enhanced ion sampling technique through the development of an ion attraction model and an ion source model.The ion attraction model demonstrates that adjusting attraction grid voltage can enhance the detection efficiency of low-energy ions and mitigate the repulsive force of ions during sampling,which is influenced by the satellite's surface positive charging.The ion source model simulates the processes of gas ionization and ion multiplication.Simulation results indicate that the GIA can achieve a lower pressure limit below 10-13Pa and possess a dynamic range exceeding 10~9.These performances ensure the generation of ions with stable and consistent current,which is crucial for high-resolution and broad dynamic range mass spectrometer analysis.Preliminary testing experiments have verified GIA's capability to detect gas compositions such as H2O and N2.In-situ measurements near 311P using GIA are expected to significantly contribute to our understanding of asteroid activity mechanisms,the evolution of the atmospheric and ionized environments of main-belt comets,the interactions with solar wind,and the origin of Earth's water.
基金Supported by the CNPC Science and Technology Project(2024ZZ0203)。
文摘The ultra-deep(deeper than 8000 m)petroleum in the platform-basin zones of the Tarim Basin has been found mainly in the Lower Paleozoic reservoirs located to the east of the strike-slip fault F5 in the north depression.However,the source and exploration potential of the ultra-deep petroleum in the Cambrian on the west of F5 are still unclear.Through the analysis of lithofacies and biomarkers,it is revealed that there are at least three kinds of isochronous source rocks(SRs)in the Cambrian Newfoundland Series in Tarim Basin,which were deposited in three sedimentary environments,i.e.sulfide slope,deep-water shelf and restricted bay.In 2024,Well XT-1 in the western part of northern Tarim Basin has yielded a high production of condensate from the Cambrian.In the produced oil,entire aryl-isoprenoid alkane biomarkers were detected,but triaromatic dinosterane was absent.This finding is well consistent with the geochemical characteristics of the Newfoundland sulfidized slope SRs represented by those in wells LT-1 and QT-1,suggesting that the Newfoundland SRs are the main source of the Cambrian petroleum discovered in Well XT-1.Cambrian crude oil of Well XT-1 also presents the predominance of C29 steranes and is rich in long-chain tricyclic terpanes(up to C39),which can be the indicators for effectively distinguishing lithofacies such as siliceous mudstone and carbonate rock.Combined with the analysis of hydrocarbon accumulation in respect of conduction systems including thrust fault and strike-slip fault,it is found that the area to the west of F5 is possible to receive effective supply of hydrocarbons from the Cambrian Newfoundland SRs in Manxi hydrocarbon-generation center.This finding suggests that the area to the west of F5 will be a new target of exploration in the Cambrian ultra-deep structural-lithologic reservoirs in the Tarim Basin,in addition to the Cambrian ultra-deep platform-margin facies-controlled reservoirs in the eastern part of the basin.
基金financially supported by the Scientific Research and Technology Development Project of China National Petroleum Corporation(No.2021ZG02)titled"Development of Seismic Data Processing Software for Ocean Nodes(OBN)"。
文摘In multi-component oil and gas exploration using ocean bottom nodes,converted wave data is rich in lithological and fracture information.One of the urgent problems to be solved is how to construct an accurate shear wave velocity model of the shallow sea bottom by leveraging the seismic wave information at the fluid-solid interface in the ocean,and improve the lateral resolution of marine converted wave data.Given that the dispersion characteristics of surface waves are sensitive to the S-wave velocity of subsurface media,and that Scholte surface waves,which propagate at the interface between liquid and solid media,exist in the data of marine oil and gas exploration,this paper proposes a Scholte wave inversion and modeling method based on oil and gas exploration using ocean bottom nodes.By using the method for calculating the Scholte wave dispersion spectrum based on the Bessel kernel function,the accuracy of dispersion spectrum analysis is improved,and more accurate dispersion curves are picked up.Through the adaptive weighted least squares Scholte wave dispersion inversion algorithm,the Scholte wave dispersion equation for liquid-solid media is solved,and the shear wave velocity model of the shallow sea bottom is calculated.Theoretical tests and applications of realdata have proven that this method can significantly improve the lateral resolution of converted wave data,provide high-quality data for subsequent inversion of marine multi-component oil and gas exploration data and reservoir reflection information,and contribute to the development of marine oil and gas exploration technology.
基金supported by the China Petroleum Science and Technology Major Project(No.2023ZZ18-03).
文摘The coal-bearing source rocks in the Jurassic Shuixigou Group have received widespread attention as the primary source rocks in the Turpan-Hami Basin of China,but the hydrocarbon generation potential and process of the mudstone in the Shuixigou Group,especially the mudstone at the top of the Sangonghe Formation,are unclear.Taking the source rocks of the Xishanyao Formation and the Sangonghe Formation as objectives,this study conducted rock pyrolysis and gold tube simulation experiment to investigate their hydrocarbon generation characteristics and differences.Our results indicate that the source rocks of the Xishanyao Formation include mudstone,carbonaceous mudstone and coal,and the quality of the source rocks is highly heterogeneous;the source rocks of the Sangonghe Formation are mainly composed of mudstone,and it is a good gas source rock.Simulation experiments found that the activation energy required for the generation of gaseous hydrocarbons by the mudstone of the Sangonghe Formation is lower than that by the mudstone of the Xishanyao Formation.The hydrocarbon generation process can be divided into three stages for both formations,but the gas generation potential of the Xishanyao Formation mudstone is higher than that of the Sangonghe Formation mudstone.A large amount of hydrocarbon was generated by the mudstone of the Xishanyao Formation when entering late thermal evolution,of which methane is dominant,mainly from the demethylation reaction of mature kerogen.On the other hand,a large amount of hydrocarbon was generated by the mudstone of the Sangonghe Formation in the early stage of thermal evolution,of which light hydrocarbon and wet gas are dominant,mainly from the early cracking stage of kerogen.This difference may be attributed to the structure of kerogen.The mudstone of the Xishanyao Formation is conducive to the formation of highly mature dry gas reservoirs,while the mudstone of the Sangonghe Formation is conducive to the formation of low maturity condensate gas and volatile oil reservoirs.The research result provides a scientific basis for the comparison of oil and gas sources and the evaluation of oil and gas resources in the Turpan-Hami Basin.
基金funded by the special project of the Department of Science and Technology,Sinopec(P23180).
文摘Three cases of structural-stratigraphic accumulations in the foredeep zone of the Oriente Basin have been analyzed.The target reservoirs are U and M1 sections of Napo Fm.in the Basin.Seismic amplitude maps are used for sand distribution pattern,and wells interpretation and correlations are applied for fluid distribution and reservoir continuity.These cases show that their oil distribution areas are significantly larger than their structure closures and thus should be structural-stratigraphic traps.But only in one case,lateral stratigraphic/lithological seals can be clearly observed.In the other two,the lateral seals are apparently discontinuous and cannot provide a complete barrier at the up-dip of the structures.Possible factors for the formation of those untypical structural-stratigraphic accumulations are studied,such as formation water flow and water head variations,basin and field structure evolution patterns,oil generation and charging history etc.An integrated mechanism is proposed in this study,where three factors may have acted together.1)Slow long distance oil migration in LU and M1 reservoirs,due to their lateral discontinuity in the foredeep of the basin.This is supported by the distal estuarine and prodelta depositional environment suggested by previous sedimentological studies.2)Ongoing secondary oil migration from south to north,caused by southward plunging and destruction of proto accumulations in the southern and middle part of the basin.This structure deformation is in turn caused by differential subsidence between the southern and northern part of the basin.3)Additional oil supplied from the southern kitchen.The southern source kitchen is still in the oil window and providing pulses of oil charge since the Oligocene.If this mechanism is valid,it would imply that in the southern and northern transition zone of the basin,similar untypical traps should also exist.The area of southern extension of the two untypical accumulation is over 50 km2,while within the basin,the transition zone of differential basin subsidence with distal and thus discontinuous LU and M1 reservoirs covers an area over 2000 km2.These findings suggest a new and potentially extensive play concept with significant exploration potential in the Oriente Basin.
基金funded by SINOPEC Science and Technology Research Program (project Nos:P24226, P24077)Northwest Oil Field Company,SINOPEC.
文摘The Cambrian platform margin in the Tarim Basin boasts favorable source-reservoir-cap assemblages,making it a significant target for hydrocarbon exploration in ultra-to extra-deep facies-controlled for-mations.Of the three major basins in western China,Tarim is the only basin with large-scale platform margin where no exploration breakthrough has been achieved yet.This study determines the vertical and lateral differential evolution of the platform margin(in the Manxi area hereafter referred to as the Cambrian Manxi platform margin)through fine-scale sequence stratigraphic division and a segmented analysis.The platform margin can be divided into the Yuqi,Tahe,Shunbei,and Gucheng segments,from north to south,based on the development of different ancient landforms and the evolutionary process of the platform.The Yuqi and Shunbei segments exhibit relatively low-elevation ancient landforms.Both segments were in a submarine buildup stage during the Early Cambrian,resulting in overall limited scales of their reservoirs.The Gucheng segment features the highest-elevation ancient landforms and accordingly limited accommodation spaces.As a result,the rapid lateral migration of high-energy facies zones leads to the development of large-scale reservoirs with only limited thicknesses.In contrast,the Tahe segment,exhibiting comparatively high-elevation ancient landforms,is identified as the most favorable segment for the formation of large-scale reservoirs.The cap rocks of the platform margin are dominated by back-reef dolomitic flats and tight carbonate rocks formed in transgressive periods.A comprehensive evaluation of source rocks,reservoirs,and cap rocks indicates that the Tahe segment boasts the optimal hydrocarbon accumulation conditions along the platform margin.In this segment,the Shayilike Formation transgressive deposits and the high-energy mound-shoal complexes along the platform margin of the Wusonggeer Formation constitute the optimal reservoir-cap rock assemblage,establishing this segment as the most promising target for hydrocarbon exploration in the platform margin.
基金Supported by the China National Science and Technology Major Project(2025ZD1403000)CNPC Major Science and Technology Project(2023ZZ19).
文摘By integrating core observations,logging data and seismic interpretation,this study takes the massive Cretaceous carbonates in the M block of the Santos Basin,Brazil,as an example to establish the sequence filling pattern of fault-bounded isolated platforms in rift lake basins,reveal the control mechanisms of shoal-body development and reservoir formation,and reconstruct the evolutionary history of lithofacies paleogeography.The following results are obtained.(1)Three tertiary sequences(SQ1-SQ3)are identified in the Lower Cretaceous Itapema-Barra Velha of the M block.During the depositional period of SQ1,the rift basement faults controlled the stratigraphic distribution pattern of thick on both sides and thin in the middle.The strata overlapped to uplift in the early stage.During the depositional period of SQ2-SQ3,the synsedimentary faults controlled the paleogeomorphic reworking process with subsidence in the northwest and uplifting in the northeast,accompanied with the relative fall of lake level.(2)The Lower Cretaceous in the M block was deposited in a littoral-shallow lake,with the lithofacies paleogeographic pattern transiting from the inner clastic shoals and outer shelly shoals in SQ1 to the alternation of mounds and shoals in SQ2-SQ3.(3)Under the joint control of relative lake-level fluctuation,synsedimentary faults and volcanic activity,the shelly shoals in SQ1 tend to accumulated vertically in the raised area,and the mound-shoal complex in SQ2-SQ3 tends to migrate laterally towards the slope-break belt due to the reduction of accommodation space.(4)The evolution pattern of high-energy mounds and shoals,which were vertically accumulated in the early stage and laterally migrated in the later stage,controlled the transformation of high-quality reservoirs from“centralized”to“ring shaped”distribution.The research findings clarify the sedimentary patterns of mounds and shoals and the distribution of favorable reservoirs in the fault-controlled lacustrine isolated platform,providing support for the deepwater hydrocarbon exploration in the subsalt carbonate rocks in the Santos Basin.
基金supported by the National Natural Science Foundation of China(Projects 42090022)。
文摘Whether clay-rich shale reservoirs with low-medium maturity can serve as primary exploration targets remains a focal point of debate in the academic community.Clarifying the exploration potential of clayrich shale reservoirs is crucial for the future exploration and development of lacustrine shale.The Triassic Yanchang Formation in the Ordos Basin has been one of most productive lacustrine shale oil systems in China,with substantial oil production capacity already established.While the primary productive layers are currently fine-grained siltstone interbeds,however,it remains a highly debated issue whether the volumetrically more significant clay-rich reservoirs can become viable exploration targets in the near future.To address this issue,we examined the exploration potential of different lithofacies assemblages in Member 7(Mbr 7)of the Triassic Yanchang Formation,using a borehole in the Tongchuan area of the southern Ordos Basin as an example.We identified favorable exploration targets and assessed whether clay-rich reservoirs formed predominantly-freshwater conditions can become viable exploration targets.The results indicate the presence of six lithofacies in clay-rich reservoirs of Mbr 7 of the Yanchang Formation,with two main lithofacies assemblages:laminated organic-rich shale and massive mudstone.From the perspective of sandstone distribution,the sandstone interlayers within laminated organic-rich shale are primarily formed by gravity(hyperpycnal)flows,while sandstones deposited in delta front environments are typically associated with massive mudstone.Laminated organic-rich shale deposition occurred in an anoxic,deep-water environment characterized by high primary productivity,whereas massive mudstone formed in environments with high sedimentation rates and substantial terrigenous debris influx.Currently,the exploration potential of sandstone interlayers exceeds that of clay-rich reservoirs,with the greatest potential observed in the sandstone interlayers associated with laminated organic-rich shale formed by gravity(hyperpycnal)flows.Comparative analysis reveals that clay-rich reservoirs with low to medium maturity present great challenges for exploitation,making interlayer-type reservoirs the main focus of exploration at this stage.Nevertheless,clay-rich reservoirs in closed systems with high thermal maturity and organic matter content also hold considerable potential.
基金the Key Laboratory of Geochemical Exploration, Institute of Geophysical and Geochemical Exploration, China Geological Survey, and Ministry of Natural Resources of the People’s Republic of China for funding this researchsupported by National Nonprofit Institute Research Grant of Institute of Geophysical and Geochemical Exploration (AS2022P03)Key Laboratory of Ionic Rare Earth Resources and Environment, Ministry of Natural Resources of the People’s Republic of China (No. 2022IRERE101 and No. 2023IRERE102)
文摘Mineral exploration under exotic overburden has been a great challenge in exploration geochemistry.Gas geochemical measurement is a potential method for mineral exploration due to the characteristics of strong penetrability and vertical migration.The previous rapid gas analyzer cannot determine low concentrations of soil gases because of inadequate sensitivity,therefore,it is necessary to develop a more sensitive analytical technique.In this paper,the pilot studies on CO_(2) and SO_(2) geochemical measurements were performed at the Zhuxi W-(Cu)deposit,Jiapigou gold ore-concentrated area,and Tukuzbay gold deposit.This study employed rapid gas analyzer based on Infrared Absorption Spectroscopy and Electrochemical Analysis,which can detect low concentrations of CO_(2) and SO_(2) and greatly improve the reliability of test data.The results show that CO_(2) and SO_(2) show clear anomalies over deeply concealed ore bodies and faults,demonstrating that CO_(2) and SO_(2) anomalies can reveal indicative information about concealed mineralization and faults.Moreover,CO_(2) and SO_(2) anomalies can identify mineralization information exceeding 1,000 m in depth,suggesting that this method has large detection depth.Therefore,CO_(2) and SO_(2) geochemical measurement method is a feasible tool to discern deeply concealed mineralization and faults,and can provide a new idea in prospecting for concealed ore deposits in covered areas.
基金supported by the National Natural Science Foundation of China (Nos. 42572017, 42172037)the State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, CAS (Nos. 213107, 173122)the International Geoscience Programme (IGCP) project 735 “Rocks and the Rise of Ordovician Life: Filling knowledge gaps in the Early Palaeozoic biodiversification”
文摘The 128.6-m-thick,shale-dominated Klimoli,Wulalike and Lashizhong formations exposed at the Hatuke Creek Section in the Zhuozishan area of Inner Monglia,North China,have been investigated for conodonts.Detailed stratigraphical collections of conodonts preserved on bedding planes from graptolitic shales,supplemented by additional discrete conodonts acid-leached from limestones,enable a refinement of the conodont biostratigraphic scheme at this section.Four successive conodont biozones,ranging in age from mid Darriwilian to late Sandbian(Stage slices Dw2–Sa2),are identified:the Dzikodus tablepointensis Biozone,the Eoplacognathus suecicus Biozone,the Pygodus serra Biozone,and the Pygodus anserinus Biozone,in ascending order.New sub-biozones,based on morphotypes of the biozonal index species,are proposed for the Pygodus serra and Pygodus anserinus biozones,providing alternatives when the traditional sub-biozones are unrecognizable.The biozonation is clearly correlated with the coeval Baltoscandian,South American and South China reference standard successions.The diverse preservation states of conodont bedding plane assemblages suggest that the alteration of conodonts in graptolitic shales represents a diagenetic process,challenging the prevailing hypothesis of pre-diagenetic dissolution.This study highlights the crucial role of previously overlooked conodont bedding plane assemblages in correlating Ordovician slope/basin facies shales,which holds great potential for marine shale gas exploration.
基金funded by SINOPEC Science and Technology Research Program(No.P23206No.P23230).
文摘Coal-measure gas is a primary target with significant potential for the exploration of unconventional hydrocarbon resources.However,the spatiotemporal distribution and combination patterns of multi-type coal-measure gases are yet to be clarified,directly impeding the sweet spot evaluation and exploration deployment of coal-measure gas.This study discussed the characteristics and distribution patterns of coal-measure gases in the Daniudi gas field in northeastern Ordos Basin,China,with abundant drilling data.The results indicate that the coal seams variably thin upward and are mainly seen in the first and second members of the Taiyuan Formation(also referred to as the Tai 1 and Tai 2 members,respectively)and the first member of the Shanxi Formation(Shan 1 Member).Nos.8,5 and 3 coal seams are laterally continuous,and significantly thicker in its southern part compared to the northern part.Moreover,carbonaceous mudstones and shales are better developed in the southern part,where limestones are only observed in the Tai 1 Member.Based on the main lithological types,we identified three lithologic roofs of coal seams,that is,limestone,mudstone,and sandstone,which determine the spatiotemporal distribution of coal-measure gases.Besides bauxite gas in the Benxi Formation,the coal-measure gases include tight-sand gas,coalbed methane(CBM),coal-measure shale gas,and tight-limestone gas,with CBM typically associated with coal-measure shale gas.The combinations of different types of coal-measure gas vary across different layers and regions.Tight-sand gas is well-developed in areas where tight sandstones are in contact with coal-measures.From the Taiyuan to the Shanxi formations,CBM gradually transitions into a combination of CBM and coal-measure shale gas,and coal-measure shale gas.Nos.8 and 5 coal seams in low-lying areas exhibit favorable gas-bearing properties due to their large thickness and favorable roof lithologies,serving as prospective play fairways.Mudstone and limestone roofs are more conducive to achieving good gas-bearing properties.The direct contact between sandstones and coal seams tends to result in the formation of tight-sand gas and a reduced gas content of CBM.While focusing on single types of gas reservoirs such as CBM and tight-sand gas,it is essential to consider the concurrent exploration of various coal-measure gas combinations to discover more additional gas resources and guide exploration deployment.
基金supported by the National Key R&D Program of China(No.2016YFC0600508).
文摘The giant Pulang porphyry copper deposit,located in the southern Yidun arc segment of southeastern Tibetan Plateau,represents one of the region’s largest mineral systems.This study employs numerical simulation to unravel its metallogenic processes.By integrating field-based geological observations with mineralogical and geochemical data,we developed a coupled model encompassing five key stages of ore formation.The simulation successfully reproduced thermal anomalies and accurately predicted the spatial distribution of mineralization zones at Pulang.Coupling dynamic modeling results with chalcopyrite precipitation rates and average Cu grades enabled quantitative estimation of deposit formation duration(0.99–1.22 Ma).Compared with conventional geochronological approaches,this process-constrained modeling framework provides unprecedented insights into the thermodynamic mechanisms controlling porphyry copper system evolution,offering valuable implications for regional exploration strategies.
基金supported by Science and technology basic resources survey special project(2022FY101701)China Geological Survey Project(DD2023350).
文摘Zirconium,prized for its exceptional corrosion resistance,high melting point,and unique nuclear properties,plays a critical role in multiple industrial sectors globally.Zirconium deposits are categorized into endogenetic and exogenetic types in China.Endogenetic deposits-including alkaline rock-,alkaline granite-,and pegmatite-type mineralizations-predominantly occur along the Tarim Craton’s northern margin,the North China Craton,the southern Greater Khingan metallogenic belt,and the Yangtze Craton’s western margin.Exogenetic deposits,comprising clastic sedimentary,weathering crust,and fragmentation types,are concentrated in South China’s coastal zones.Endogenetic mineralization formed during Permian-Cretaceous magmatic-hydrothermal events linked to evolved alkaline granitic systems,while exogenetic deposits developed in Quaternary periods through weathering of zirconium-rich protoliths.However,economic extraction of endogenetic deposits remains constrained by rare earth element(REE)associations and radioactive complexities.Currently,China’s most economically significant reserves derive from clastic sedimentary systems,particularly coastal placer deposits.This study systematically synthesizes the spatial distribution and metallogenic mechanisms of Chinese zirconium deposits,offering strategic insights for resource exploration and sustainable utilization.
基金Supported by National Key R&D Program of China(2020YFE0202100)Beijing Municipal Science and Technology Commission(Z181100002918003)。
文摘China has carried out four unmanned missions to the Moon since it launched Chang’E-1,the first lunar orbiter in 2007.With the implementation of the Chang’E-5 mission this year,the three phases of the lunar exploration program,namely orbiting,landing and returning,have been completed.In the plan of follow-up unmanned lunar exploration missions,it is planned to establish an experimental lunar research station at the lunar south pole by 2030 through the implementation of several missions,laying a foundation for the establishment of practical lunar research station in the future.China successfully launched its first Mars probe on 23 July 2020,followed in future by an asteroid mission,second Mars mission,and a mission to explore Jupiter and its moons.
