Tectonic activities significantly impact deep reservoir properties via sedimentary and diagenetic processes,and this is particularly true for lacustrine rift basins.The tectonic-sedimentary-diageneticreservoir system ...Tectonic activities significantly impact deep reservoir properties via sedimentary and diagenetic processes,and this is particularly true for lacustrine rift basins.The tectonic-sedimentary-diageneticreservoir system is crucial in deep reservoir exploration.This study examined the first member and upper submember of the second member of the Dongying Formation in the Bodong Low Uplift in the Bohai Bay Basin(East China),documenting the petrologic features and physical properties of reservoirs in different tectonic sub-units through integrated analysis of log and rock data,along with core observation.A mechanism for deep reservoir formation in lacustrine rift basins was developed to elucidate the sedimentary and diagenetic processes in complex tectonic settings.The results show that tectonic activities result in the occurrence of provenances in multiple directions and the existence of reservoirs at varying burial depths,as well as the significant diversity in sedimentary and diagenetic processes.The grain sizes of the sandstones,influenced by transport pathways rather than the topography of the sedimentary area,exhibit spatial complexity due to tectonic frameworks,which determine the initial pore content of reservoirs.However,the burial depth,influenced by subsequent tectonic subsidence,significantly impacts pore evolution during diagenesis.Based on the significant differences of reservoirs in slope zone,low uplift and depression zone,we establish different tectonic-diagenetic models in deep complex tectonic units of lacustrine rift basins.展开更多
Uplift of segmental linings in shield tunnels presents considerable challenges,potentially compromising the structural integrity of tunnels.The uplift movement can be physically modelled using a Timoshenko beam on a W...Uplift of segmental linings in shield tunnels presents considerable challenges,potentially compromising the structural integrity of tunnels.The uplift movement can be physically modelled using a Timoshenko beam on a Winkler foundation.This study introduces an innovative method employing a physicsinformed neural network(PINN)to solve the governing differential equations of shield tunnel linings under specifiedboundary conditions,known loads,and foundation parameters.Importantly,the PINN does not rely on empirical data for training;instead,it incorporates physics-based constraints to accurately capture spatial variations in load and foundation stiffness during grouting and construction phases.The PINN model was validated with fielddata from a shield tunnel in the Pazhou branch of the Guangzhou-Dongguan-Shenzhen intercity railway line.The results demonstrate the effectiveness of the model in predicting segment uplift.Furthermore,compared to traditional analytical solutions,the PINN model provides a more realistic representation of fieldconditions by integrating spatial variations in loading and foundation support.展开更多
An enhanced understanding of the history of the western Qinling-Dabie orogen is pivotal in reconstructing geological processes of the east Asian mainland.However,less attention has been paid to its early-stage uplift-...An enhanced understanding of the history of the western Qinling-Dabie orogen is pivotal in reconstructing geological processes of the east Asian mainland.However,less attention has been paid to its early-stage uplift-erosion history after closure of surrounding oceanic basins at the mid-Paleozoic.In this study,we undertook a comprehensive study including paleocurrent reconstruction,sandstone petrology,and detrital zircon U-Pb dating on Late Carboniferous to Early Permian successions in the southern Ordos neighboring the northern Qinling-Dabie.New provenance data reveal a significant provenance shift at the Carboniferous-Permian transition.The older Benxi Formation was sourced southerly from the North Qinling Terrane that provided detritus mostly of Neoproterozoic and Early Paleozoic ages.In contrast,Early Permian samples yield age relation dominated by Neoarchean,Paleoproterozoic,Early Paleozoic,and Late Paleozoic age populations,with a significant gap of ca.1600-550 Ma,implying a sediment derivation from the Inner Mongolia Continental Arc.This shift is further verified by paleocurrent transition from south to north then.We suggest that the North Qinling Terrane experienced a significant uplift history from ca.500 Ma and remained as a highland until end-Carboniferous.From Early Permian,the North Qinling Terrane was submerged,covered by widespread deltaic sedimentation there.Northerly source from the Inner Mongolia Continental Arc began to be accumulated in the northern flank of the North Qinling Terrane,before termination approximately along the southern North Qinling Terrane,where shallow-water carbonate shelf sedimentation sustained from Devonian to Triassic.This new finding indicates that uplift of the North Qinling Terrane lasted about 150 Ma after the Proto-Tethys Ocean closure.展开更多
A numerical simulation approach was adopted to investigate the uplift bearing characteristics of helical an-chors in Nantong silty sand and to predict their uplift bear-ing capacity.Finite element model validation was...A numerical simulation approach was adopted to investigate the uplift bearing characteristics of helical an-chors in Nantong silty sand and to predict their uplift bear-ing capacity.Finite element model validation was per-formed,and the uplift bearing mechanism of helical anchors was analyzed.The current code’s uplift bearing capacity calculation formula was optimized,and the accuracy and re-liability of the modified formula were evaluated.The results indicate that the critical embedment depth ratio of the anchor plate in Nantong silty sand is 5,and the critical spacing ra-tio ranges from 3 to 4.The current code’s formula underes-timates the uplift bearing capacity of helical anchors under these conditions.To improve the prediction accuracy,the optimization coefficients M and L,which account for the embedment depth ratio of the anchor plate,are introduced,and fitting formulas for these coefficients are provided to im-prove the prediction of uplift bearing capacity in Nantong silty sand and to serve as a reference for similar engineering applications.展开更多
This study addresses the significant disparity in aerodynamic uplift forces experienced by single-strip high-speed pantographs under different operating directions.A systematic numerical investigation was conducted to...This study addresses the significant disparity in aerodynamic uplift forces experienced by single-strip high-speed pantographs under different operating directions.A systematic numerical investigation was conducted to evaluate the influence of key geometric parameters on aerodynamic characteristics,culminating in two targeted adjustment strategies.The reliability of the computational methodology was validated through comparative analysis,which revealed less than a 6%deviation in aerodynamic drag between the numerical simulations and wind tunnel tests.Aerodynamic decomposition revealed that the operating direction critically impacts the uplift force,which is governed by two factors:streamwise cross-strip positioning and the angular orientation of the arm hinge.These factors collectively determine the divergent aerodynamic responses of the panhead and frame during directional changes.By establishing a parametric database encompassing four strip-to-crossbar spacing configurations and six arm diameter variations,nonlinear response patterns of the uplift forces under different operating directions to geometric modifications were quantified.Both adjustment approaches,simultaneously reducing both streamwise and vertical strip-to-crossbar spacings to half of the original dimensions or increasing the upper arm spanwise diameter to 1.45 times and decreasing the lower arm spanwise diameter to 0.55 times the baseline values,successfully constrained aerodynamic uplift force deviations between operating directions within 3%.展开更多
With the increasing construction of port facilities,cross-sea bridges,and offshore engineering projects,uplift piles embedded in marine sedimentary soft soil are becoming increasingly necessary.The load-displacement c...With the increasing construction of port facilities,cross-sea bridges,and offshore engineering projects,uplift piles embedded in marine sedimentary soft soil are becoming increasingly necessary.The load-displacement curve of uplift piles is crucial for evaluating their uplift bearing characteristics,which facilitates the risk evaluation,design,and construction of large infrastructural supports.In this study,a load-displacement curve model based on piezocone penetration test(CPTU)data is proposed via the load transfer method.Experimental tests are conducted to analyze the uplift bearing characteristics and establish a correlation between the proposed model and CPTU data.The results of the proposed load-displacement curve are compared with the results from numerical simulations and those calculated by previous methods.The results show that the proposed curves appropriately evaluated the uplift bearing characteristics and improved the accuracy in comparison with previous methods.展开更多
0 INTRODUCTION The Qilian Mountain Belt,at the forefront of the Tibetan Plateau's expansion,offers key insights into the plateau's tectonic deformation(Zuza et al.,2018;Zheng et al.,2010;Zhang et al.,2004;Tapp...0 INTRODUCTION The Qilian Mountain Belt,at the forefront of the Tibetan Plateau's expansion,offers key insights into the plateau's tectonic deformation(Zuza et al.,2018;Zheng et al.,2010;Zhang et al.,2004;Tapponnier et al.,2001;Meyer et al.,1998).The northwest-trending mountain ranges in the Qilian Shan(“Shan”means“Mountain”in Chinese)have significantly influenced this deformation(Zheng et al.,2013).展开更多
The Mesozoic volcanic rocks of the Bodong Low Uplift in the Bohai Bay Basin have been studied and explored for years.In 2024,the LK7-A well drilled in this region tested high-yield oil and gas flows from volcanic weat...The Mesozoic volcanic rocks of the Bodong Low Uplift in the Bohai Bay Basin have been studied and explored for years.In 2024,the LK7-A well drilled in this region tested high-yield oil and gas flows from volcanic weathered crust.These volcanic rocks need to be further investigated in terms of distribution patterns,conditions for forming high-quality reservoirs,and main factors controlling hydrocarbon accumulation.Based on the logging,geochemical and mineralogical data from wells newly drilled to the Mesozoic volcanic rocks in the basin,and high-resolution 3D seismic data,a comprehensive study was conducted for this area.The research findings are as follows.First,the volcanic rocks in the LK7-A structure are adakites with a large source area depth,and the deep and large faults have provided channels for the emplacement of intermediate-acidic volcanic rocks.Second,volcanic rock reservoirs are mainly distributed in tectonic breccias and intermediate-acidic lavas,and they are dominantly fractured-porous reservoirs,with high-porosity and low-permeability or medium-porosity and low-permeability.Third,the dominant lithologies/lithofacies is the basic condition for forming large-scale volcanic rock reservoirs.Structural fractures and late-stage strong weathering are crucial mechanisms for the formation scale of reservoirs in the Mesozoic volcanic rocks.Fourth,the Bodong Low Uplift exhibits strong hydrocarbon charging by two sags and overpressure mudstone capping,which are favorable for forming high-abundance oil and gas reservoirs.The Mesozoic volcanic buried hills in the study area reflect good trap geometry,providing favorable conditions for large-scale reservoir formation,and also excellent migration and accumulation conditions.Areas with long-term exposure of intermediate-acidic volcanic rocks,particularly in active structural regions,are the key targets for future exploration.展开更多
Mesozoic-Palaeozoic marine carbonate rocks are crucial hydrocarbon reservoirs in the Central Uplift area of the South Yellow Sea Basin(SYSB).Due to the scarcity of boreholes and the significant heterogeneity of carbon...Mesozoic-Palaeozoic marine carbonate rocks are crucial hydrocarbon reservoirs in the Central Uplift area of the South Yellow Sea Basin(SYSB).Due to the scarcity of boreholes and the significant heterogeneity of carbonate reservoirs,the distribution of porous carbonate reservoirs and their related key controlling factors remain unclear.In this study,factors affecting the distribution of porous Carboniferous-Early Permian carbonate reservoirs in the SYSB were investigated through seismic inversion and isotope analysis.The log-seismic characteristics of porous carbonate reservoirs,sensitive lithology parameters,and physical property parameters were extracted and analyzed.The pre-stack simultaneous inversion technique was applied to predict the lithology and physical properties of porous carbonate reservoirs.Moreover,the sedimentary of carbonate was analyzed using isotopes of carbon,oxygen,and strontium.The results show that porous carbonate reservoirs are mainly developed in the open platform sediments with porosities of 3%-5%and are mainly distributed in the paleo-highland(Huanglong Formation and Chuanshan Formation)and the slope of paleo-highland(Hezhou Formation).The porous carbonate reservoirs of the Qixia Formation are only locally developed.In addition,the negativeδ13C excursions indicate a warm and humid tropical climate with three sea-level fluctuations in the study area from the Carboniferous to Early Permian.The favorable conditions for developing porous carbonate rocks include the sedimentary environment and diagenetic process.The primary pore tends to form in high-energy environments of the paleo-highland,and the secondary pore is increased by dissolution during the syngenetic or quasi-syngenetic period.According to the hydrocarbon potential analysis,the Late Ordovician Wufeng Formation and Lower Silurian Gaojiabian Formation are the source rocks in the high-maturity-over-maturity stage,the Carboniferous-Lower Permian carbonate is the good reservoirs,and the Late Permian Longtan-Dalong Formation is the stable seal,ensuring a huge hydrocarbon accumulation potential in SYSB.The methods proposed in this study can be applied to other carbonate-dominated strata worldwide.展开更多
The Huimin（惠民） depression is a third-level tectonic element of the Bohai（渤海） Bay basin in eastern China.The central uplift belt is the most important oil and gas accumulation zone in the depression,but the lac...The Huimin（惠民） depression is a third-level tectonic element of the Bohai（渤海） Bay basin in eastern China.The central uplift belt is the most important oil and gas accumulation zone in the depression,but the lack of adequate geological studies in the area has greatly hindered exploration and development.In this article,using seismic data,fracture mechanics,and a combination of data on fault growth indices and fault throws,we present an analysis of tectonic activity in the central uplift belt and adjacent regions.The amount of extension is calculated along balanced N-S cross-sections,along with the thickness of strata eroded from the fourth,third,and second members of the Shahejie（沙河街） Formation（Es4-Es2） in the uplift belt,by analyzing porosity and stratigraphic correlations.In addition,uplift features are described,and their timing and processes of formation are analyzed and dis-cussed.The results indicate that strike-slip and extensional tectonic movements coexisted,with the effects of the latter most obvious.The spatial and temporal nature of the extensional move-ments is varied：fault activity during the period Ek-Es4 was the strongest on the northern Ningnan（宁南） fault,and activity in the western part of the area was stronger than that in the east,which in turn was stronger than that in the central region;during Es3-Es2,the strongest fault movements were along the eastern part of the middle Linyi（临邑） fault,and activity in the western part of the area was rela-tively weak,whereas in the mid-west it was the strongest.The extensional movements were a response to the activity of the faults.The sediments in the lower part of the fourth member of the Shahejie For-mation（Es4x） show that Es4 was the time when the central belt first began to be uplifted strongly.Uplift was uneven during the Paleogene：the western part of the area was uplifted continuously,while the mid-eastern area underwent alternating periods of uplift and subsidence.During the Paleogene,a number of different tectonic features developed in the central uplift belt at different times and are manifested as follows：during the period Ek-Es4,a gentle slope was formed as part of the Zizhen（滋镇） sag;during Es3-Es2,the northern part of the central uplift belt continued to display a gentle slope as part of the Zizhen sag,but the southern region developed an steep slope as part of the Linnan（临南） sag.There are close interrelationships between uplift,strike-slip,and extension within the central uplift belt of the Huimin depression,as is manifest by the areas of strongest extension being uplifted most rapidly,and also eroded the most.展开更多
Rock-embedded foundations with good uplift and bearing capacity are often used in mountains or hilly areas.However,there are soil layers with a certain thickness on the rocks in these mountainous areas,and the utiliza...Rock-embedded foundations with good uplift and bearing capacity are often used in mountains or hilly areas.However,there are soil layers with a certain thickness on the rocks in these mountainous areas,and the utilization of those soil layers is a problem worthy of attention in foundation construction.Considering construction-and cost-related factors,traditional single-form foundations built on such sites often cannot provide sufficient resistance against uplift.Therefore,an anchored pier foundation composed of anchors and belled piers,specifically constructed for such conditions,can be invaluable in practice.This paper introduces an experimental and analytical study to investigate the uplift capacity and the uplift mobilization coefficients(UMCs)of the anchored pier foundation.In this study,three in-situ monotonic pullout tests were carried out to analyze the load–displacement characteristics,axial force distribution,load transfer mechanism,and failure mechanism.A hyperbolic model is used to fit the load–displacement curves and to reveal the asynchrony of the ultimate limit states(ULSs)of the anchor group and the belled pier.Based on the results,the uplift capacity can be calculated by the UMCs and the anchor group and pier uplift capacities.Finally,combined with the estimation of the deformation modulus of the soil and rock,the verification calculation of the uplift capacity and UMC was carried out on the test results from different anchored pier foundations.展开更多
The uplift is a positive structural unit of the crust. It is an important window for continental dynamics owing to its abundant structural phenomena, such as fault, fold, unconformity and denudation of strata. Meanwhi...The uplift is a positive structural unit of the crust. It is an important window for continental dynamics owing to its abundant structural phenomena, such as fault, fold, unconformity and denudation of strata. Meanwhile, it is the very place to store important minerals like oil, natural gas, coal and uranium. Giant and large-scale oil and gas fields in China, such as the Daqing Oilfield, Lunnan-Tahe Oilfield, Penglai 19-3 Oilfield, Puguang Gas Field and Jingbian Gas Field, are developed mainly on uplifts. Therefore, it is the main target both for oil and gas exploration and for geological study. The uplift can be either a basement uplift, or one developed only in the sedimentary cover. Extension, compression and wrench or their combined forces may give rise to uplifts. The development process of uplifting, such as formation, development, dwindling and destruction, can be taken as the uplifting cycle. The uplifts on the giant Precambrian cratons are large in scale with less extensive structural deformation. The uplifts on the medium- and small-sized cratons or neo-cratons are formed in various shapes with strong structural deformation and complicated geological structure. Owing to changes in the geodynamic environment, uplift experiences a multi-stage or multi-cycle development process. Its geological structure is characterized in superposition of multi-structural layers. Based on the basement properties, mechanical stratigraphy and development sequence, uplifts can be divided into three basic types-the succession, superposition and destruction ones. The succession type is subdivided into the maintaining type and the lasting type. The superposition type can be subdivided into the composite anticlinal type, the buried-hill draped type, the faulted uplift type and the migration type according to the different scales and superimposed styles of uplifts in different cycles. The destruction type is subdivided into the tilting type and the negative inverted type. The development history of uplifts and their controlling effects on sedimentation and fluids are quite different from one another, although the uplifts with different structural types store important minerals. Uplifts and their slopes are the main areas for oil and gas accumulation. They usually become the composite oil and gas accumulation zones （belts） with multiple productive formations and various types of oil and gas reservoirs.展开更多
Geologists agree that the collision of the Indian and Asian plates caused uplift of the Tibet Plateau. However, controversy still exists regarding the modes and mechanisms of the Tibetan Plateau uplift. Geology has re...Geologists agree that the collision of the Indian and Asian plates caused uplift of the Tibet Plateau. However, controversy still exists regarding the modes and mechanisms of the Tibetan Plateau uplift. Geology has recorded this uplift well in the Qaidam Basin. This paper analyzes the tectonic and sedimentary evolution of the western Qaidam Basin using sub-surface seismic and drill data. The Cenozoic intensity and history of deformation in the Qaidam Basin have been reconstructed based on the tectonic developments, faults growth index, sedimentary facies variations, and the migration of the depositional depressions. The changes in the sedimentary facies show that lakes in the western Qaidam Basin had gone from inflow to still water deposition to withdrawal. Tectonic movements controlled deposition in various depressions, and the depressions gradually shifted southeastward. In addition, the morphology of the surface structures in the western Qaidam Basin shows that the Cenozoic tectonic movements controlled the evolution of the Basin and divided it into （a） the southern fault terrace zone, （b） a central Yingxiongling orogenic belt, and （c） the northern fold-thrust belt; divided by the XI fault （Youshi fault） and Youbei fault, respectively. The field data indicate that the western Qaidam Basin formed in a Cenozoic compressive tectonic environment caused by the India--Asia plate collision. Further, the Basin experienced two phases of intensive tectonic deformation. The first phase occurred during the Middle Eocene--Early Miocene （Xia Ganchaigou Fm. and Shang Ganchaigou Fro., 43.8- 22 Ma）, and peaked in the Early Oligocene （Upper Xia Ganchaigou Fro., 31.5 Ma）. The second phase occurred between the Middle Miocene and the Present （Shang Youshashan Fro. and Qigequan Fro., 14.9-0 Ma）, and was stronger than the first phase. The tectonic--sedimentary evolution and the orienta- tion of surface structures in the western Qaidam Basin resulted from the Tibetan Plateau uplift, and recorded the periodic northward growth of the Plateau. Recognizing this early tectonic--sedimentary evolution supports the previous conclusion that northern Tibet responded to the collision between India and Asia shortly after its initiation. However, the current results reveal that northern Tibet also experi- enced another phase of uplift during the late Neogene. The effects of these two stages of tectonic activity combined to produce the current Tibetan Plateau.展开更多
Based on fission track dating of apatite, and measurement of vitrinite reflectance of rock samples from the Longmenshan (Longmen Mountain)area and the West Sichuan foreland basin and computer modelling it is concluded...Based on fission track dating of apatite, and measurement of vitrinite reflectance of rock samples from the Longmenshan (Longmen Mountain)area and the West Sichuan foreland basin and computer modelling it is concluded that (l)the Songpan-Garze fold belt has uplifted at least by 3-4 km with an uplift rate of no less than 0.3-0.4 mm/a since 10 Ma B.P.; (2) the Longmenshan thrust nappe belt has uplifted at least by 5-6 km with an uplift rate of more than 0.5- 0.6 mm /a since 10 Ma B.P.; (3) the Longmenshan detachment belt has uplifted by 1 - 2 km at a rate of 0.016-0.032 mm/a since 60 Ma B.P.; (4) the West Sichuan foreland basin has uplifted by 1.7-3 km at a rate of 0.028-0.05 mm/a since 60 Ma B.P.; (5) the uplift rate of the area on the west side of the Beichuan-Yingxiu-Xiaoguanzi fault for the last 10 Ma is 40 times as much as that on its east side; (6) the uplifting of the the Songpan - Garze fold belt and the subsidence of the West Sichuan foreland basin 60 Ma ago exhibit a mirro-image correlation, i.e. the rapid uplifting of the the Songpan-Garze fold belt was corresponding to the rapid subsidence of the basin;the Songpan-Garze fold belt has uplifted at a much greater rate than the West Sichuan foeland basin in the last 60 Ma;and (7) the palaeogeothermal gradient was 25℃ /km in the West Sichuan foreland basin.展开更多
A global atmospheric general circulation model has been used to perform eleven idealized numerical experiments, i.e., TP10, TP10, .., TP100, corresponding to different percentages of the Tibetan Plateau altitude. The ...A global atmospheric general circulation model has been used to perform eleven idealized numerical experiments, i.e., TP10, TP10, .., TP100, corresponding to different percentages of the Tibetan Plateau altitude. The aim is to explore the sensitivity of East Asian climate to the uplift and expansion of the Tibetan Plateau under the reconstructed boundary conditions for the mid-Pliocene about 3 Ma ago. When the plateau is progressively uplifted, global annual surface temperature is gradually declined and statistically significant cooling signals emerge only in the Northern Hemisphere, especially over and around the Tibetan Plateau, with larger magnitudes over land than over the oceans. On the contrary, annual surface temperature rises notably over Central Asia and most parts of Africa, as well as over northeasternmost Eurasia in the experiments TP60 to TP100. Meanwhile, the plateau uplift also leads to annual precipitation augmentation over the Tibetan Plateau but a reduction in northern Asia, the Indian Peninsula, much of Central Asia, parts of western Asia and the southern portions of northeastern Europe. Additionally, it is found that an East Asian summer monsoon system similar to that of the present initially exists in the TP60 and is gradually intensified with the continued plateau uplift. At 850 hPa the plateau uplift induces an anomalous cyclonic circulation around the Tibetan Plateau in summertime and two anomalous westerly currents respectively located to the south and north of the Tibetan Plateau in wintertime. In the mid-troposphere, similarto-modern spatial pattern of summertime western North Pacific subtropical high is only exhibited in the experiments TP60 to TP100, and the East Asian trough is steadily deepened in response to the progressive uplift and expansion of the Tibetan Plateau.展开更多
The origin of the unusually high dibenzothiophene （DBT） concentrations in Lower Ordovician oils from the Tazhong Uplift,Tarim Basin was studied by Fourier transform ion cyclotron resonance mass spectrometry （FT-ICR...The origin of the unusually high dibenzothiophene （DBT） concentrations in Lower Ordovician oils from the Tazhong Uplift,Tarim Basin was studied by Fourier transform ion cyclotron resonance mass spectrometry （FT-ICR MS）.The most abundant sulfur compounds in the oils are S 1 species with doublebond equivalent （DBE） values of 1-19 and 11-48 carbon atoms.The range of the number of carbon atoms in the sulfur compounds detected by the FT-ICR MS （S 1 species with DBE=9） is about ten times larger than that for sulfur compounds detected by GC/MS （DBTs）.This suggests that FT-ICR MS is a much better approach than GC/MS for characterization of DBTs in crude oils.The abundance of S 1 species with DBE=1-8 decreased with increasing thermal maturity,while the abundance of S 1 species with DBE=9 （primarily DBTs） increased.Therefore,thermal maturity is an important factor in the formation of oils with high DBT concentrations.Unusually high abundances of S 1 species with low DBE values （1-8）,which include sulfide,thiophene and benzothiophene,were observed in several oils,especially the TZ83 （O 1） oil with high or very high thermal maturity.Thermochemical sulfate reduction （TSR） was thought to be the reason for the high abundance of these low DBE compounds in deep reservoirs,and thermochemical sulfate reduction could affect the distribution and composition of DBTs in the oils.According to the results of FT-ICR MS analysis,there are no signs that TSR is occurring or has occurred recently for most of the Lower Ordovician oils.展开更多
Seismic sedimentology is a new frontier inter-discipline subject, and shows good prospect and potentiality in reservoir deposition research with seismic data and geophysics technologies. We made seismic sedimentology ...Seismic sedimentology is a new frontier inter-discipline subject, and shows good prospect and potentiality in reservoir deposition research with seismic data and geophysics technologies. We made seismic sedimentology research of shallow sea area, gentle slope belt of Chengning （埕宁） uplift, Bohalwan （渤海湾） basin. In shallow sea area with sparse well coverage, it was difficult to characterize the reservoir architecture with the traditional method based on wells. A new method to resolve the above problems is built： （1） information on plane and in section is inter-ealibrated with each other; （2） recognize the isochronic surfaces by frequency decomposition and interpret the depositional character with technology of stratal slicing; （3） make a comprehensive research with the stratal slice interpreta- tion and the dissection of well group. The depositional model of this area is built and used in the architecture analysis of area without wells. The architecture description reveals that the sedimentary character of pan-connection sand bodies in braided rivers is the reason for high water cut of the new horizontal wells. .展开更多
基金funded by the Open Fund of Key Laboratory of Marine Geology and Environment,Chinese Academy of Sciences(Grant No.MGE2020KG10)the Open Fund of Key Laboratory of Submarine Geosciences,Ministry of Natural Resources(Grant No.KLSG 2208)+2 种基金the Natural Science Basic Research Program of Shaanxi(Grant No.2024JC-YBMS-227,2023-JC-QN-0287)the Postgraduate Innovation and Practice Ability Development Fund of Xi'an Shiyou University(No.YCS23113046)the National Natural Science Foundation of China(Grant No.41802128,42076219)。
文摘Tectonic activities significantly impact deep reservoir properties via sedimentary and diagenetic processes,and this is particularly true for lacustrine rift basins.The tectonic-sedimentary-diageneticreservoir system is crucial in deep reservoir exploration.This study examined the first member and upper submember of the second member of the Dongying Formation in the Bodong Low Uplift in the Bohai Bay Basin(East China),documenting the petrologic features and physical properties of reservoirs in different tectonic sub-units through integrated analysis of log and rock data,along with core observation.A mechanism for deep reservoir formation in lacustrine rift basins was developed to elucidate the sedimentary and diagenetic processes in complex tectonic settings.The results show that tectonic activities result in the occurrence of provenances in multiple directions and the existence of reservoirs at varying burial depths,as well as the significant diversity in sedimentary and diagenetic processes.The grain sizes of the sandstones,influenced by transport pathways rather than the topography of the sedimentary area,exhibit spatial complexity due to tectonic frameworks,which determine the initial pore content of reservoirs.However,the burial depth,influenced by subsequent tectonic subsidence,significantly impacts pore evolution during diagenesis.Based on the significant differences of reservoirs in slope zone,low uplift and depression zone,we establish different tectonic-diagenetic models in deep complex tectonic units of lacustrine rift basins.
基金funded by“The Pearl River Talent Recruitment Program”in 2019(Grant No.2019CX01G338)Guangdong Province and Guangdong Provincial Basic and Applied Basic Research Fund Committee(2022A1515240073).
文摘Uplift of segmental linings in shield tunnels presents considerable challenges,potentially compromising the structural integrity of tunnels.The uplift movement can be physically modelled using a Timoshenko beam on a Winkler foundation.This study introduces an innovative method employing a physicsinformed neural network(PINN)to solve the governing differential equations of shield tunnel linings under specifiedboundary conditions,known loads,and foundation parameters.Importantly,the PINN does not rely on empirical data for training;instead,it incorporates physics-based constraints to accurately capture spatial variations in load and foundation stiffness during grouting and construction phases.The PINN model was validated with fielddata from a shield tunnel in the Pazhou branch of the Guangzhou-Dongguan-Shenzhen intercity railway line.The results demonstrate the effectiveness of the model in predicting segment uplift.Furthermore,compared to traditional analytical solutions,the PINN model provides a more realistic representation of fieldconditions by integrating spatial variations in loading and foundation support.
基金the National Natural Science Foundation of China(Grant Nos:42372253 and 42072260)the Youth Innovation Team of Shaanxi Universitiesthe Science and Technology Project of PetroChina(No.2023ZZ0201).
文摘An enhanced understanding of the history of the western Qinling-Dabie orogen is pivotal in reconstructing geological processes of the east Asian mainland.However,less attention has been paid to its early-stage uplift-erosion history after closure of surrounding oceanic basins at the mid-Paleozoic.In this study,we undertook a comprehensive study including paleocurrent reconstruction,sandstone petrology,and detrital zircon U-Pb dating on Late Carboniferous to Early Permian successions in the southern Ordos neighboring the northern Qinling-Dabie.New provenance data reveal a significant provenance shift at the Carboniferous-Permian transition.The older Benxi Formation was sourced southerly from the North Qinling Terrane that provided detritus mostly of Neoproterozoic and Early Paleozoic ages.In contrast,Early Permian samples yield age relation dominated by Neoarchean,Paleoproterozoic,Early Paleozoic,and Late Paleozoic age populations,with a significant gap of ca.1600-550 Ma,implying a sediment derivation from the Inner Mongolia Continental Arc.This shift is further verified by paleocurrent transition from south to north then.We suggest that the North Qinling Terrane experienced a significant uplift history from ca.500 Ma and remained as a highland until end-Carboniferous.From Early Permian,the North Qinling Terrane was submerged,covered by widespread deltaic sedimentation there.Northerly source from the Inner Mongolia Continental Arc began to be accumulated in the northern flank of the North Qinling Terrane,before termination approximately along the southern North Qinling Terrane,where shallow-water carbonate shelf sedimentation sustained from Devonian to Triassic.This new finding indicates that uplift of the North Qinling Terrane lasted about 150 Ma after the Proto-Tethys Ocean closure.
基金The National Natural Science Foundation of China (No. 52378329)。
文摘A numerical simulation approach was adopted to investigate the uplift bearing characteristics of helical an-chors in Nantong silty sand and to predict their uplift bear-ing capacity.Finite element model validation was per-formed,and the uplift bearing mechanism of helical anchors was analyzed.The current code’s uplift bearing capacity calculation formula was optimized,and the accuracy and re-liability of the modified formula were evaluated.The results indicate that the critical embedment depth ratio of the anchor plate in Nantong silty sand is 5,and the critical spacing ra-tio ranges from 3 to 4.The current code’s formula underes-timates the uplift bearing capacity of helical anchors under these conditions.To improve the prediction accuracy,the optimization coefficients M and L,which account for the embedment depth ratio of the anchor plate,are introduced,and fitting formulas for these coefficients are provided to im-prove the prediction of uplift bearing capacity in Nantong silty sand and to serve as a reference for similar engineering applications.
基金supported by the Major Project of China Railway Co.,Ltd.(Grant No.K2021J004-A).
文摘This study addresses the significant disparity in aerodynamic uplift forces experienced by single-strip high-speed pantographs under different operating directions.A systematic numerical investigation was conducted to evaluate the influence of key geometric parameters on aerodynamic characteristics,culminating in two targeted adjustment strategies.The reliability of the computational methodology was validated through comparative analysis,which revealed less than a 6%deviation in aerodynamic drag between the numerical simulations and wind tunnel tests.Aerodynamic decomposition revealed that the operating direction critically impacts the uplift force,which is governed by two factors:streamwise cross-strip positioning and the angular orientation of the arm hinge.These factors collectively determine the divergent aerodynamic responses of the panhead and frame during directional changes.By establishing a parametric database encompassing four strip-to-crossbar spacing configurations and six arm diameter variations,nonlinear response patterns of the uplift forces under different operating directions to geometric modifications were quantified.Both adjustment approaches,simultaneously reducing both streamwise and vertical strip-to-crossbar spacings to half of the original dimensions or increasing the upper arm spanwise diameter to 1.45 times and decreasing the lower arm spanwise diameter to 0.55 times the baseline values,successfully constrained aerodynamic uplift force deviations between operating directions within 3%.
基金supported by the China Postdoctoral Science Foundation(Grant No.2024M760734)National Science Fund for Distinguished Young Scholars(Grant No.42225206)the National Natural Science Foundation of China(Grant Nos.41877231 and 42072299).
文摘With the increasing construction of port facilities,cross-sea bridges,and offshore engineering projects,uplift piles embedded in marine sedimentary soft soil are becoming increasingly necessary.The load-displacement curve of uplift piles is crucial for evaluating their uplift bearing characteristics,which facilitates the risk evaluation,design,and construction of large infrastructural supports.In this study,a load-displacement curve model based on piezocone penetration test(CPTU)data is proposed via the load transfer method.Experimental tests are conducted to analyze the uplift bearing characteristics and establish a correlation between the proposed model and CPTU data.The results of the proposed load-displacement curve are compared with the results from numerical simulations and those calculated by previous methods.The results show that the proposed curves appropriately evaluated the uplift bearing characteristics and improved the accuracy in comparison with previous methods.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(No.2019QZKK0901)the State Key Laboratory of Earthquake Dynamics(No.LED2023B04)+1 种基金the National Natural Science Foundation of China(Nos.42272242,W2411033,W2521003)the Science and Technology Plan of Gansu Province(No.22JR11RA088)。
文摘0 INTRODUCTION The Qilian Mountain Belt,at the forefront of the Tibetan Plateau's expansion,offers key insights into the plateau's tectonic deformation(Zuza et al.,2018;Zheng et al.,2010;Zhang et al.,2004;Tapponnier et al.,2001;Meyer et al.,1998).The northwest-trending mountain ranges in the Qilian Shan(“Shan”means“Mountain”in Chinese)have significantly influenced this deformation(Zheng et al.,2013).
基金Supported by the the National Natural Science Foundation of China(U24B2017)。
文摘The Mesozoic volcanic rocks of the Bodong Low Uplift in the Bohai Bay Basin have been studied and explored for years.In 2024,the LK7-A well drilled in this region tested high-yield oil and gas flows from volcanic weathered crust.These volcanic rocks need to be further investigated in terms of distribution patterns,conditions for forming high-quality reservoirs,and main factors controlling hydrocarbon accumulation.Based on the logging,geochemical and mineralogical data from wells newly drilled to the Mesozoic volcanic rocks in the basin,and high-resolution 3D seismic data,a comprehensive study was conducted for this area.The research findings are as follows.First,the volcanic rocks in the LK7-A structure are adakites with a large source area depth,and the deep and large faults have provided channels for the emplacement of intermediate-acidic volcanic rocks.Second,volcanic rock reservoirs are mainly distributed in tectonic breccias and intermediate-acidic lavas,and they are dominantly fractured-porous reservoirs,with high-porosity and low-permeability or medium-porosity and low-permeability.Third,the dominant lithologies/lithofacies is the basic condition for forming large-scale volcanic rock reservoirs.Structural fractures and late-stage strong weathering are crucial mechanisms for the formation scale of reservoirs in the Mesozoic volcanic rocks.Fourth,the Bodong Low Uplift exhibits strong hydrocarbon charging by two sags and overpressure mudstone capping,which are favorable for forming high-abundance oil and gas reservoirs.The Mesozoic volcanic buried hills in the study area reflect good trap geometry,providing favorable conditions for large-scale reservoir formation,and also excellent migration and accumulation conditions.Areas with long-term exposure of intermediate-acidic volcanic rocks,particularly in active structural regions,are the key targets for future exploration.
基金This study was supported by the project ofthe Science and Technology Innovation Fund of Command Center of Natural Resources Intergrated Survey entitled“Temporal and spatial distribution of paleochannel and origin of organic carbon burial in the Western Bohai Sea since 2.28Ma”(KC20220011)the project entitled“Characterization of Carboniferous-Early Permian heterogeneous porous carbonate reservoirs and hydrocarbon potential analysis in the central uplift of the South Yellow Sea Basin”(KLSG2304)+3 种基金by the Key laboratory of Submarine Science,Ministry of Natural Resources,the project entitled“1∶50000 Marine regional Geological survey in Caofeidian Sea Area,Bohai Sea”(ZD20220602)“1∶250000 Marine regional Geological survey in Weihai Sea Area,North Yellow Sea”(DD20230412)“Geological survey on tectonic and sedimentary conditions of Laoshan uplift”(DD2016015)by the China Geological Survey,and the project entitled“Study on Hydrocarbon Accumulation Failure and Fluid Evolution Reduction of the Permian Reservoir in the Laoshan Uplift,South Yellow Sea”(42076220)organized by the National Natural Science Foundation of China.
文摘Mesozoic-Palaeozoic marine carbonate rocks are crucial hydrocarbon reservoirs in the Central Uplift area of the South Yellow Sea Basin(SYSB).Due to the scarcity of boreholes and the significant heterogeneity of carbonate reservoirs,the distribution of porous carbonate reservoirs and their related key controlling factors remain unclear.In this study,factors affecting the distribution of porous Carboniferous-Early Permian carbonate reservoirs in the SYSB were investigated through seismic inversion and isotope analysis.The log-seismic characteristics of porous carbonate reservoirs,sensitive lithology parameters,and physical property parameters were extracted and analyzed.The pre-stack simultaneous inversion technique was applied to predict the lithology and physical properties of porous carbonate reservoirs.Moreover,the sedimentary of carbonate was analyzed using isotopes of carbon,oxygen,and strontium.The results show that porous carbonate reservoirs are mainly developed in the open platform sediments with porosities of 3%-5%and are mainly distributed in the paleo-highland(Huanglong Formation and Chuanshan Formation)and the slope of paleo-highland(Hezhou Formation).The porous carbonate reservoirs of the Qixia Formation are only locally developed.In addition,the negativeδ13C excursions indicate a warm and humid tropical climate with three sea-level fluctuations in the study area from the Carboniferous to Early Permian.The favorable conditions for developing porous carbonate rocks include the sedimentary environment and diagenetic process.The primary pore tends to form in high-energy environments of the paleo-highland,and the secondary pore is increased by dissolution during the syngenetic or quasi-syngenetic period.According to the hydrocarbon potential analysis,the Late Ordovician Wufeng Formation and Lower Silurian Gaojiabian Formation are the source rocks in the high-maturity-over-maturity stage,the Carboniferous-Lower Permian carbonate is the good reservoirs,and the Late Permian Longtan-Dalong Formation is the stable seal,ensuring a huge hydrocarbon accumulation potential in SYSB.The methods proposed in this study can be applied to other carbonate-dominated strata worldwide.
基金supported by the Natural Science Foundation of Shandong Province (No. ZR2009EQ002)the Foundation of the Shandong Provincial Key Laboratory of Depositional Mineralization & Sedimentary Minerals (No. DMSM201005)+1 种基金the National Natural Science Foundation of China (No. 90814006)the Project of Excellent Young College Teachers Home Visiting Scholar during 2009 in Shandong Province, and the Postgraduate Innovation Foundation of Shandong University of Science and Technology (No. YCB100112)
文摘The Huimin（惠民） depression is a third-level tectonic element of the Bohai（渤海） Bay basin in eastern China.The central uplift belt is the most important oil and gas accumulation zone in the depression,but the lack of adequate geological studies in the area has greatly hindered exploration and development.In this article,using seismic data,fracture mechanics,and a combination of data on fault growth indices and fault throws,we present an analysis of tectonic activity in the central uplift belt and adjacent regions.The amount of extension is calculated along balanced N-S cross-sections,along with the thickness of strata eroded from the fourth,third,and second members of the Shahejie（沙河街） Formation（Es4-Es2） in the uplift belt,by analyzing porosity and stratigraphic correlations.In addition,uplift features are described,and their timing and processes of formation are analyzed and dis-cussed.The results indicate that strike-slip and extensional tectonic movements coexisted,with the effects of the latter most obvious.The spatial and temporal nature of the extensional move-ments is varied：fault activity during the period Ek-Es4 was the strongest on the northern Ningnan（宁南） fault,and activity in the western part of the area was stronger than that in the east,which in turn was stronger than that in the central region;during Es3-Es2,the strongest fault movements were along the eastern part of the middle Linyi（临邑） fault,and activity in the western part of the area was rela-tively weak,whereas in the mid-west it was the strongest.The extensional movements were a response to the activity of the faults.The sediments in the lower part of the fourth member of the Shahejie For-mation（Es4x） show that Es4 was the time when the central belt first began to be uplifted strongly.Uplift was uneven during the Paleogene：the western part of the area was uplifted continuously,while the mid-eastern area underwent alternating periods of uplift and subsidence.During the Paleogene,a number of different tectonic features developed in the central uplift belt at different times and are manifested as follows：during the period Ek-Es4,a gentle slope was formed as part of the Zizhen（滋镇） sag;during Es3-Es2,the northern part of the central uplift belt continued to display a gentle slope as part of the Zizhen sag,but the southern region developed an steep slope as part of the Linnan（临南） sag.There are close interrelationships between uplift,strike-slip,and extension within the central uplift belt of the Huimin depression,as is manifest by the areas of strongest extension being uplifted most rapidly,and also eroded the most.
基金supported by the National Natural Science Foundation of China(No.U2006225)the European Union’s Horizon 2020 Marie Sklodowska-Curie Research and Innovation Staff Exchange Programme(No.778360)。
文摘Rock-embedded foundations with good uplift and bearing capacity are often used in mountains or hilly areas.However,there are soil layers with a certain thickness on the rocks in these mountainous areas,and the utilization of those soil layers is a problem worthy of attention in foundation construction.Considering construction-and cost-related factors,traditional single-form foundations built on such sites often cannot provide sufficient resistance against uplift.Therefore,an anchored pier foundation composed of anchors and belled piers,specifically constructed for such conditions,can be invaluable in practice.This paper introduces an experimental and analytical study to investigate the uplift capacity and the uplift mobilization coefficients(UMCs)of the anchored pier foundation.In this study,three in-situ monotonic pullout tests were carried out to analyze the load–displacement characteristics,axial force distribution,load transfer mechanism,and failure mechanism.A hyperbolic model is used to fit the load–displacement curves and to reveal the asynchrony of the ultimate limit states(ULSs)of the anchor group and the belled pier.Based on the results,the uplift capacity can be calculated by the UMCs and the anchor group and pier uplift capacities.Finally,combined with the estimation of the deformation modulus of the soil and rock,the verification calculation of the uplift capacity and UMC was carried out on the test results from different anchored pier foundations.
基金co-supported by the National Key Basic Research and Development Program of China(No.2006CB202300)the National Natural Science Foundation Important Project(No.40739906).
文摘The uplift is a positive structural unit of the crust. It is an important window for continental dynamics owing to its abundant structural phenomena, such as fault, fold, unconformity and denudation of strata. Meanwhile, it is the very place to store important minerals like oil, natural gas, coal and uranium. Giant and large-scale oil and gas fields in China, such as the Daqing Oilfield, Lunnan-Tahe Oilfield, Penglai 19-3 Oilfield, Puguang Gas Field and Jingbian Gas Field, are developed mainly on uplifts. Therefore, it is the main target both for oil and gas exploration and for geological study. The uplift can be either a basement uplift, or one developed only in the sedimentary cover. Extension, compression and wrench or their combined forces may give rise to uplifts. The development process of uplifting, such as formation, development, dwindling and destruction, can be taken as the uplifting cycle. The uplifts on the giant Precambrian cratons are large in scale with less extensive structural deformation. The uplifts on the medium- and small-sized cratons or neo-cratons are formed in various shapes with strong structural deformation and complicated geological structure. Owing to changes in the geodynamic environment, uplift experiences a multi-stage or multi-cycle development process. Its geological structure is characterized in superposition of multi-structural layers. Based on the basement properties, mechanical stratigraphy and development sequence, uplifts can be divided into three basic types-the succession, superposition and destruction ones. The succession type is subdivided into the maintaining type and the lasting type. The superposition type can be subdivided into the composite anticlinal type, the buried-hill draped type, the faulted uplift type and the migration type according to the different scales and superimposed styles of uplifts in different cycles. The destruction type is subdivided into the tilting type and the negative inverted type. The development history of uplifts and their controlling effects on sedimentation and fluids are quite different from one another, although the uplifts with different structural types store important minerals. Uplifts and their slopes are the main areas for oil and gas accumulation. They usually become the composite oil and gas accumulation zones （belts） with multiple productive formations and various types of oil and gas reservoirs.
基金co-supposed by the Knowledge Innovation Program of the Chinese Academy of Sciences(No.KZCX2-EW-ON112)Open Fund of Key Laboratory of Petroleum Resources Research of the Chinese Academy of Sciences(No.KFJJ2010-07)
文摘Geologists agree that the collision of the Indian and Asian plates caused uplift of the Tibet Plateau. However, controversy still exists regarding the modes and mechanisms of the Tibetan Plateau uplift. Geology has recorded this uplift well in the Qaidam Basin. This paper analyzes the tectonic and sedimentary evolution of the western Qaidam Basin using sub-surface seismic and drill data. The Cenozoic intensity and history of deformation in the Qaidam Basin have been reconstructed based on the tectonic developments, faults growth index, sedimentary facies variations, and the migration of the depositional depressions. The changes in the sedimentary facies show that lakes in the western Qaidam Basin had gone from inflow to still water deposition to withdrawal. Tectonic movements controlled deposition in various depressions, and the depressions gradually shifted southeastward. In addition, the morphology of the surface structures in the western Qaidam Basin shows that the Cenozoic tectonic movements controlled the evolution of the Basin and divided it into （a） the southern fault terrace zone, （b） a central Yingxiongling orogenic belt, and （c） the northern fold-thrust belt; divided by the XI fault （Youshi fault） and Youbei fault, respectively. The field data indicate that the western Qaidam Basin formed in a Cenozoic compressive tectonic environment caused by the India--Asia plate collision. Further, the Basin experienced two phases of intensive tectonic deformation. The first phase occurred during the Middle Eocene--Early Miocene （Xia Ganchaigou Fm. and Shang Ganchaigou Fro., 43.8- 22 Ma）, and peaked in the Early Oligocene （Upper Xia Ganchaigou Fro., 31.5 Ma）. The second phase occurred between the Middle Miocene and the Present （Shang Youshashan Fro. and Qigequan Fro., 14.9-0 Ma）, and was stronger than the first phase. The tectonic--sedimentary evolution and the orienta- tion of surface structures in the western Qaidam Basin resulted from the Tibetan Plateau uplift, and recorded the periodic northward growth of the Plateau. Recognizing this early tectonic--sedimentary evolution supports the previous conclusion that northern Tibet responded to the collision between India and Asia shortly after its initiation. However, the current results reveal that northern Tibet also experi- enced another phase of uplift during the late Neogene. The effects of these two stages of tectonic activity combined to produce the current Tibetan Plateau.
基金the National Natural Science Foundation of china (poject No. 49070140)
文摘Based on fission track dating of apatite, and measurement of vitrinite reflectance of rock samples from the Longmenshan (Longmen Mountain)area and the West Sichuan foreland basin and computer modelling it is concluded that (l)the Songpan-Garze fold belt has uplifted at least by 3-4 km with an uplift rate of no less than 0.3-0.4 mm/a since 10 Ma B.P.; (2) the Longmenshan thrust nappe belt has uplifted at least by 5-6 km with an uplift rate of more than 0.5- 0.6 mm /a since 10 Ma B.P.; (3) the Longmenshan detachment belt has uplifted by 1 - 2 km at a rate of 0.016-0.032 mm/a since 60 Ma B.P.; (4) the West Sichuan foreland basin has uplifted by 1.7-3 km at a rate of 0.028-0.05 mm/a since 60 Ma B.P.; (5) the uplift rate of the area on the west side of the Beichuan-Yingxiu-Xiaoguanzi fault for the last 10 Ma is 40 times as much as that on its east side; (6) the uplifting of the the Songpan - Garze fold belt and the subsidence of the West Sichuan foreland basin 60 Ma ago exhibit a mirro-image correlation, i.e. the rapid uplifting of the the Songpan-Garze fold belt was corresponding to the rapid subsidence of the basin;the Songpan-Garze fold belt has uplifted at a much greater rate than the West Sichuan foeland basin in the last 60 Ma;and (7) the palaeogeothermal gradient was 25℃ /km in the West Sichuan foreland basin.
基金the Chinese Academy of Sciences under Grant Nos. KZCX2-YW-205 and KZCX3-SW-229the National NaturalScience Foundation of China under Grant Nos. 40505017and 40775052.
文摘A global atmospheric general circulation model has been used to perform eleven idealized numerical experiments, i.e., TP10, TP10, .., TP100, corresponding to different percentages of the Tibetan Plateau altitude. The aim is to explore the sensitivity of East Asian climate to the uplift and expansion of the Tibetan Plateau under the reconstructed boundary conditions for the mid-Pliocene about 3 Ma ago. When the plateau is progressively uplifted, global annual surface temperature is gradually declined and statistically significant cooling signals emerge only in the Northern Hemisphere, especially over and around the Tibetan Plateau, with larger magnitudes over land than over the oceans. On the contrary, annual surface temperature rises notably over Central Asia and most parts of Africa, as well as over northeasternmost Eurasia in the experiments TP60 to TP100. Meanwhile, the plateau uplift also leads to annual precipitation augmentation over the Tibetan Plateau but a reduction in northern Asia, the Indian Peninsula, much of Central Asia, parts of western Asia and the southern portions of northeastern Europe. Additionally, it is found that an East Asian summer monsoon system similar to that of the present initially exists in the TP60 and is gradually intensified with the continued plateau uplift. At 850 hPa the plateau uplift induces an anomalous cyclonic circulation around the Tibetan Plateau in summertime and two anomalous westerly currents respectively located to the south and north of the Tibetan Plateau in wintertime. In the mid-troposphere, similarto-modern spatial pattern of summertime western North Pacific subtropical high is only exhibited in the experiments TP60 to TP100, and the East Asian trough is steadily deepened in response to the progressive uplift and expansion of the Tibetan Plateau.
基金funded by the Natural Science FundingCouncil of China(Grant No.#40973031)the Foundationof State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum(No.PRPJC2008-02)Natural Science Research Council of China(China 973 National Key Research and Development Program 2011CB201102)
文摘The origin of the unusually high dibenzothiophene （DBT） concentrations in Lower Ordovician oils from the Tazhong Uplift,Tarim Basin was studied by Fourier transform ion cyclotron resonance mass spectrometry （FT-ICR MS）.The most abundant sulfur compounds in the oils are S 1 species with doublebond equivalent （DBE） values of 1-19 and 11-48 carbon atoms.The range of the number of carbon atoms in the sulfur compounds detected by the FT-ICR MS （S 1 species with DBE=9） is about ten times larger than that for sulfur compounds detected by GC/MS （DBTs）.This suggests that FT-ICR MS is a much better approach than GC/MS for characterization of DBTs in crude oils.The abundance of S 1 species with DBE=1-8 decreased with increasing thermal maturity,while the abundance of S 1 species with DBE=9 （primarily DBTs） increased.Therefore,thermal maturity is an important factor in the formation of oils with high DBT concentrations.Unusually high abundances of S 1 species with low DBE values （1-8）,which include sulfide,thiophene and benzothiophene,were observed in several oils,especially the TZ83 （O 1） oil with high or very high thermal maturity.Thermochemical sulfate reduction （TSR） was thought to be the reason for the high abundance of these low DBE compounds in deep reservoirs,and thermochemical sulfate reduction could affect the distribution and composition of DBTs in the oils.According to the results of FT-ICR MS analysis,there are no signs that TSR is occurring or has occurred recently for most of the Lower Ordovician oils.
基金supported by the National Natural Science Foundation of China (No. 40872094)the Natural Science Foundation of Shandong Province (No. Z2008E01)
文摘Seismic sedimentology is a new frontier inter-discipline subject, and shows good prospect and potentiality in reservoir deposition research with seismic data and geophysics technologies. We made seismic sedimentology research of shallow sea area, gentle slope belt of Chengning （埕宁） uplift, Bohalwan （渤海湾） basin. In shallow sea area with sparse well coverage, it was difficult to characterize the reservoir architecture with the traditional method based on wells. A new method to resolve the above problems is built： （1） information on plane and in section is inter-ealibrated with each other; （2） recognize the isochronic surfaces by frequency decomposition and interpret the depositional character with technology of stratal slicing; （3） make a comprehensive research with the stratal slice interpreta- tion and the dissection of well group. The depositional model of this area is built and used in the architecture analysis of area without wells. The architecture description reveals that the sedimentary character of pan-connection sand bodies in braided rivers is the reason for high water cut of the new horizontal wells. .
