This work proposes and fabricates the 4H-SiC power MOSFET with top oxide and double P-well(TODP-MOSFET)to enhance the single-event radiation tolerance of the gate oxide.Simulation results suggest that the proposed TOD...This work proposes and fabricates the 4H-SiC power MOSFET with top oxide and double P-well(TODP-MOSFET)to enhance the single-event radiation tolerance of the gate oxide.Simulation results suggest that the proposed TODP structure reduces the peak electric field within the oxide and minimizes the sensitive region by more than 70%compared to C-MOSFETs.Experimental results show that the gate degradation voltage of the TODP-MOSFET is higher than that of the C-MOSFET,and the gate leakage current is reduced by 95%compared to the C-MOSFET under heavy-ion irradiation with a linear energy transfer(LET)value exceeding 75 MeV·cm^(2)/mg.展开更多
Diseases associated with bacterial infection,especially those caused by gram-negative bacteria,have been posing a serious threat to human health.Photodynamic therapy based on aggregation-induced emission(AIE)photosens...Diseases associated with bacterial infection,especially those caused by gram-negative bacteria,have been posing a serious threat to human health.Photodynamic therapy based on aggregation-induced emission(AIE)photosensitizer have recently emerged and provided a promising approach for bacterial discrimination and efficient photodynamic antimicrobial applications.However,they often suffer from the shorter excitation wavelength and lower molar extinction coefficients in the visible region,severely limiting their further applications.Herein,three novel BF_(2)-curcuminoid-based AIE photosensitizers,TBBC,TBC and TBBC-C8,have been rationally designed and successfully developed,in which OCH_(3)-and OC_(8)H_(17)-substituted tetraphenylethene(TPE)groups serve as both electron donor(D)and AIE active moieties,BF_(2)bdk group functions as electron acceptor(A),and styrene(or ethylene)group asπ-bridge in this D-π-A-π-D system,respectively.As expected,these resulting BF_(2)-curcuminoids presented solvent-dependent photophysical properties with large molar extinction coefficients in solutions and excellent AIE properties.Notably,TBBC showed an effective singlet oxygen generation efficiency thanks to the smaller singlet-triplet energy gap(△E_(ST)),and remarkable photostability under green light exposure at 530nm(8.9 mW/cm^(2)).More importantly,TBBC was demonstrated effectiveness in selective staining and photodynamic killing of Escherichia coli(E.coli)in vitro probably due to its optimal molecular size compared with TBC and TBBC-C8.Therefore,TBBC will have great potential as a novel AIE photosensitizer to apply in the discrimination and selective sterilization between Gram-positive and Gram-negative bacteria.展开更多
Determining the timing of fracturing is crucial for understanding reservoir evolution and hydrocarbon accumulation in foreland basins.Using fracturing data from cores,borehole images,and outcrops,combined with the clu...Determining the timing of fracturing is crucial for understanding reservoir evolution and hydrocarbon accumulation in foreland basins.Using fracturing data from cores,borehole images,and outcrops,combined with the clumped isotope(D47)and fluid inclusion analyses of carbonate minerals filled in pores and fractures,this study ascertained the fracturing timing of the Jurassic reservoirs in the Dibei-Tuziluoke Gas Field,Kuqa Foreland Basin.Data from outcrops and borehole images show two dominant fracture sets in the study area:W-E and NE-SW striking fractures.Some W-E striking fractures are carbonate-filled,while NE-SW striking fractures lack mineral fillings.Bitumen veins,not easy to be identified in borehole images,are prevalent in cores.The petrographic analysis reveals that these bitumen veins formed before the calcite cementation in pores and display high viscosity and low maturity.Homogenization temperatures(T_(h))from primary fluid inclusion assemblages in two representative calcite vein samples were notably lower than T_(△47) values from corresponding samples.This suggests the △_(47) signature underwent alteration due to partial reordering during burial.Thus,△_(47)-derived temperatures(apparent temperatures)may not faithfully represent the mineral precipitation temperatures.When plotting these apparent temperatures vs.the burial history,only the possible latest ages of fracturing emerged.These ages were further refined by considering petroleum charging,tectonic evolution,and stress orientation.Bitumen-filled fractures likely resulted from the Late Cretaceous uplift,marking the migration of low-maturity hydrocarbons in the study area.Carbonate-filled E-W striking fractures emerged during the late Miocene(~13-6.5 Ma)alongside fold development.NE-striking fractures that crosscut W-E ones possibly formed recently due to stress reorientation.展开更多
The discovery and large-scale exploration of unconventional oil/gas resources since 1980s have been considered as the most important advancement in the history of petroleum geology;that has not only changed the balanc...The discovery and large-scale exploration of unconventional oil/gas resources since 1980s have been considered as the most important advancement in the history of petroleum geology;that has not only changed the balance of supply and demand in the global energy market,but also improved our understanding of the formation mechanisms and distribution characteristics of oil/gas reservoirs.However,what is the difference of conventional and unconventional resources and why they always related to each other in petroliferous basins is not clear.As the differences and correlations between unconventional and conventional resources are complex challenging issues and very critical for resources assessment and hydrocarbon exploration,this paper focused on studying the relationship of formations and distributions among different oil/gas reservoirs.Drilling results of 12,237 exploratory wells in 6 representative petroliferous basins of China and distribution characteristics for 52,926 oil/gas accumulations over the world were applied to clarify the formation conditions and genetic relations of different oil/gas reservoirs in a petroliferous basin,and then to establish a unified model to address the differences and correlations of conventional and unconventional reservoirs.In this model,conventional reservoirs formed in free hydrocarbon dynamic field with high porosity and permeability located above the boundary of hydrocarbon buoyancy-driven accumulation depth limit.Unconventional tight reservoirs formed in confined hydrocarbon dynamic field with low porosity and permeability located between hydrocarbon buoyancy-driven accumulation depth limit and hydrocarbon accumulation depth limit.Shale oil/gas reservoirs formed in the bound hydrocarbon dynamic field with low porosity and ultra-low permeability within the source rock layers.More than 75%of proved reserves around the world are discovered in the free hydrocarbon dynamic field,which is estimated to contain only 10%of originally generated hydrocarbons.Most of undiscovered resources distributed in the confined hydrocarbon dynamic field and the bound hydrocarbon dynamic field,which contains 90%of original generated hydrocarbons,implying a reasonable and promising area for future hydrocarbon explorations.The buried depths of hydrocarbon dynamic fields become shallow with the increase of heat flow,and the remaining oil/gas resources mainly exist in the deep area of“cold basin”with low geothermal gradient.Lithology changing in the hydrocarbon dynamic field causes local anomalies in the oil/gas dynamic mechanism,leading to the local formation of unconventional hydrocarbon reservoirs in the free hydrocarbon dynamic field or the occurrence of oil/gas enrichment sweet points with high porosity and permeability in the confined hydrocarbon dynamic field.The tectonic movements destroy the medium conditions and oil/gas components,which leads to the transformation of conventional oil/gas reservoirs formed in free hydrocarbon dynamic field to unconventional ones or unconventional ones formed in confined and bound hydrocarbon dynamic fields to conventional ones.展开更多
Three dimensional (3D) microscopic distributions of dolomite and calcite in a limestone sample have been analyzed with a data-constrained modeling (DCM) technique using synchrotron radiation-based multi-energy X-ray c...Three dimensional (3D) microscopic distributions of dolomite and calcite in a limestone sample have been analyzed with a data-constrained modeling (DCM) technique using synchrotron radiation-based multi-energy X-ray computed tomography (CT) data as constraints. In order to optimize the experimental parameters, X-ray CT simulations and DCM analysis of a numerical phantom consisting of calcite (CaCO3) and dolomite (CaMg(CO3)2) have been used to investigate the effects on the predicted results in relation to noise, X-ray energy and sample-to-detector distance (SDD). The simulation results indicate that the optimal X-ray energies are 25 and 35 keVs, and the SDD is 10 mm. The high resolution 3D distributions of mineral phases of a natural limestone have been obtained. The results are useful for quantitative understanding of mineral, porosity, and physical property distributions in relation to oil and gas reservoirs hosted in carbonate rocks, which account for more than half of the world’s conventional hydrocarbon resources. The case studied is also instructive for the applicability of the DCM methods for other types of composite materials with modest atomic number contrasts between the mineral phases.展开更多
Recent decades have witnessed an increasing number of studies investigating petroleum systems with the application of rhenium-osmium(Re-Os) isotopic geochemistry. Here, we review the use of the 187 Re-187 Os geochrono...Recent decades have witnessed an increasing number of studies investigating petroleum systems with the application of rhenium-osmium(Re-Os) isotopic geochemistry. Here, we review the use of the 187 Re-187 Os geochronometer with respect to the geochemical behaviour of rhenium and osmium in hydrocarbon-related geological processes. The Re-Os budget in hydrocarbon source rock predominantly originates from natural water columns during its deposition. Open seawater tends to have a homogeneous Os isotopic composition because its residence time in seawater is longer than the time taken for ocean mixing. On the contrary, restricted water bodies(e.g., lakes) may have heterogeneous Os isotopic compositions due to the greater amount of terrigenous input. Hydrogenous Re and Os atoms are sequestered from the water body into sedimentary organic matter and transferred into crude oil through thermal maturation of organic matter. Thermal maturation likely does not significantly alter the Re-Os isotopic systematics of the source rock as a Re-Os isochron age of 442±21 Ma(2σ) is yielded in this study for over matured source rocks within the Silurian Longmaxi Formation from the Sichuan Basin. Re-Os atoms are mainly hosted by the highly polar/aggregating/aromatic asphaltenes in hydrocarbons, possibly chelating with organic complexes or occurring as metalloporphyrins. Resin and aromatic hydrocarbons also contribute to the Re-Os budget, but are 2 to 3 orders of magnitude lower than that of asphaltenes, whereas saturates do not contain appreciable Re-Os contents. The distribution of Re-Os atoms in hydrocarbons is heterogeneous because the duplicate analysis of pure single bitumen samples yields similar ^(187)Os/^(188)Os ratios whereas variable ^(187)Re/^(188)Os ratios. The Re-Os system in crude oils can be reset during transport away from the source rocks, with Os-rich organic fractions more readily expelled than Re-rich fractions. Contact with metal-rich fluids(e.g., hydrothermal fluid) or compositional changes related to asphaltene contents(e.g., deasphalting, biodegradation, thermal cracking and thermochemical sulphate reduction) are also likely to alter the Re-Os systematics in hydrocarbons. These geochemical features enable the ^(187)Re-^(187)Os isotopic system to have robust applicability for petroleum system investigations, which may use the Re-Os radiometric tool for:(1) stratigraphic correlation of source rocks,(2) dating geological events altering the asphaltene content in hydrocarbon such as hydrocarbon generation, thermochemical sulphate reduction, etc., and,(3) fingerprinting hydrocarbons. Regardless of the robustness of the ^(187)Re-^(187)Os geochronometer for petroleum system investigations, there are several pending questions such as partitioning between solid organic species or between organic matter and sulphide, chelating sites in hydrocarbons and Os isotopic equilibration between hydrocarbon subfractions. To improve the understanding of the Re-Os behaviour in petroleum systems, we underscore multi-proxies-based geochemistry(e.g., inorganic-organic geochemistry) and experimental studies(e.g., hydrous pyrolysis).展开更多
Sorption isotherms of hydrocarbon and carbon dioxide （CO2） provide crucial information for designing processes to sequester CO2 and recover natural gas from unmineable coal beds. Methane （CH4）, ethane （C2H6）, an...Sorption isotherms of hydrocarbon and carbon dioxide （CO2） provide crucial information for designing processes to sequester CO2 and recover natural gas from unmineable coal beds. Methane （CH4）, ethane （C2H6）, and CO2 adsorption isotherms on dry coal and the temperature effect on their maximum sorption capacity have been studied by performing combined Monte Carlo （MC） and molecular dynamics （MD） simulations at temperatures of 308 and 370 K （35 and 97 ~C） and at pressures up to 10 MPa. Simulation results demonstrate that absolute sorption （expressed as a mass basis） divided by bulk gas density has negligible temperature effect on CH4, C2H6, and CO2 sorption on dry coal when pressure is over 6 MPa. CO2 is more closely packed due to stronger interaction with coal and the stronger interaction between CO2 mole- cules compared, respectively, with the interactions between hydrocarbons and coal and between hydrocarbons. The results of this work suggest that the ＂a＂ constant （pro- portional to TcPc） in the Peng-Robinson equation of state is an important factor affecting the sorption behavior of hydrocarbons. CO2 injection pressures of lower than 8 MPa may be desirable for CH4 recovery and CO2 sequestration. This study provides a quantitative under- standing of the effects of temperature on coal sorptioncapacity for CH4, C2H6, and CO2 from a microscopic perspective.展开更多
An attempt is made in this paper to present the dynamics of the Eastern Niger Rift Basin (ENRB) with references to the key features and processes of petroleum systems based on published information. The Eastern Niger ...An attempt is made in this paper to present the dynamics of the Eastern Niger Rift Basin (ENRB) with references to the key features and processes of petroleum systems based on published information. The Eastern Niger Basin is a superimposed rift basin with sedimentary structures emplaced during two rifts episodes. The Cretaceous episode is characterized by large, tilted normally faulted blocks trending NW-SE, that were reactivated in the Paleogene, while the Paleogene episode is characterized by normal faulted blocks that trend NNW-SSE. The rifting resulted in different basin structures with the north section dominated by asymmetric half-grabens while the south section is dominated by full-grabens. Three source rocks each belonging to three different play fairways exist: 1) The Paleogene Sokor-1 Member source belongs to second cycle syn-rift play associated with fluvial/deltaic facies;2) Cretaceous Yogou and Donga sources from first cycle post-rift play associated with alluvial/fluvial/deltaic and marine clastic and carbonate facies;and 3) Cretaceous Yogou source from first cycle transitional play associated with mudstone and shale of transitional facies. The ENRB comprises two source-reservoir-seal assemblages: a lower assemblage of Upper Cretaceous and an Upper assemblage of the Paleogene. Except for the Yogou source which possesses a self-contained petroleum system, the rest of the source rocks release their oils into the Paleogene Sokor-1 Member reservoir sealed regionally by the Oligocene Sokor-2 Member. The Paleogene assemblage is charged from the Upper Cretaceous Yogou Formation through fractures emplaced during the rifting episodes.展开更多
Tectonic transition from a syn-rift stage to subsequent post-rift stage is an important mechanism in the evolution of extensional basins.The sedimentary infill records the crustal response to this process.We have obta...Tectonic transition from a syn-rift stage to subsequent post-rift stage is an important mechanism in the evolution of extensional basins.The sedimentary infill records the crustal response to this process.We have obtained new detrital zircon U-Pb and Lu-Hf signatures from the Lower Cretaceous stratigraphic successions encompassing the commonly accepted syn-to post-rift transition boundary,the T4 unconformity,in the Songliao Basin,NE China.These constrain the Songliao Basin’s evolution from its center to distal margins,providing insights into the sediment provenance and dispersal pattern over the tectonic transition.Analysis of zircons from the syn-rift(the Shahezi and Yingcheng formations)and immediate post-rift(the Lower and Middle Denglouku Formation)stages reveals Phanerozoic age populations with positiveƐHf(t)values,which were derived from the proximal juvenile mantle-derived melt origin bedrocks of the Songliao Block.In contrast,the overlying samples from the Upper Denglouku Formation deposited in the subsequent post-rift stage contain exotic and ancient zircon populations with ages of 2.5 Ga&1.8 Ga and complex hafnium signatures,characteristic of a mixed origin.These are interpreted to be transported from distant cratonic terranes via larger drainage networks.It is obvious that the sediment dispersal pattern switched from being a local and hydrologically closed“intraregional”pattern to a“transcontinental”pattern during the transition.The time lag between the development of the T4 unconformity and the drainage reorganization also ensures a distinguishable3 Myr(106103 Ma,Late Albian)transition period of regional extent.During this transition stage,syn-rift faulting was replaced by postrift thermal subsidence,exhibiting a uniform sag configuration.Our new findings are important for understanding other continental rift basins during syn-to post-rift transition,which often demonstrates a complex interaction between the linkage and integration of sub-basins,and the reorganization of fluvial drainages and catchment systems.展开更多
Feldspar minerals are widely present in clastic reservoirs of hydrocarbon-bearing basins,where they undergo significant dissolution during burial processes.The dissolution kinetics and evolutionary trends of feldspar ...Feldspar minerals are widely present in clastic reservoirs of hydrocarbon-bearing basins,where they undergo significant dissolution during burial processes.The dissolution kinetics and evolutionary trends of feldspar under burial conditions are critical for the formation of secondary porosity and the evolution of reservoir spaces.The feldspar dissolution process is frequently associated with the precipitation and transformation of complex authigenic minerals,making it challenging to accurately determine dissolution rates under near-equilibrium conditions.This study performed experimental simulations of feldspar(K-feldspar and albite)dissolution under conditions ranging from far-from-equilibrium to near-equilibrium,with varying temperatures and pCO_(2).Under near-equilibrium conditions,scanning electron microscopy(SEM),energy-dispersive spectroscopy(EDS),and laser confocal microscopy were employed to achieve accurate quantification of the dissolution volume of feldspar samples.The dissolution rates of feldspar under near-equilibrium conditions,along with the factors influencing these rates,were systematically investigated.The results indicate that the dissolution rates of K-feldspar under near-equilibrium conditions at temperatures and pCO_(2)levels of 80℃/1 bar,120℃/4.2 bar,and 160℃/17.9 bar are 2.16695×10^(15)–8.040×10^(15),4.49288×10^(15)–1.480×10^(14),and 6.17462×10^(15)–2.496×10^(14)mol cm^(-2)s^(-1),respectively.Under the same near-equilibrium conditions,the dissolution rates of albite are 2.93294×10^(15)–1.365×10^(14),5.54499×10^(15)–2.170×10^(14),and 9.42841×10^(15)–3.074×10^(14)mol cm^(-2)s^(-1),respectively.The dissolution rates of feldspar under near-equilibrium conditions are significantly lower(1.5–2orders of magnitude at high temperatures)than those under far-equilibrium conditions.Furthermore,as the temperature increases by a gradient of 40℃,the dissolution rate only increases by only 1.5 times,which is substantially lower than the rate increase observed under far-equilibrium conditions.The discrepancy between feldspar dissolution rates under far-equilibrium conditions(L-TST)and near-equilibrium conditions increases with rising temperature.Under identical experimental conditions,the dissolution rate of albite under near-equilibrium conditions is higher than that of K-feldspar.The precipitation and transformation of secondary minerals regulate feldspar dissolution under near-equilibrium conditions by altering ion concentrations in the solution.The p H of the solution also plays a significant role in controlling feldspar dissolution under near-equilibrium conditions.This study establishes a method for quantitatively analyzing mineral dissolution using the surface morphological features of dissolved and undissolved segments of polished feldspar samples.This method avoids relying on changes in ion concentrations in the reaction solution,making it more reasonable and widely applicable.Moreover,the results provide valuable insights into feldspar dissolution kinetics under burial conditions within closed systems,enabling a more accurate assessment of the contribution of feldspar dissolution to pore formation in reservoirs.展开更多
Continental deformation on the Earth's surface is an extremely complex geological process,in which the formation and evolution of sedimentary basins are closely related to plate motions and mantle activities.Combi...Continental deformation on the Earth's surface is an extremely complex geological process,in which the formation and evolution of sedimentary basins are closely related to plate motions and mantle activities.Combining sedimentary basins with orogenic belts and sedimentary responses with tectonic activities can comprehensively elucidate the geological processes during the Earth's evolution.This paper focuses on the multi-stage evolution of the Ordos Basin,the coupled basin-mountain systems and energy resources,discusses the evolution of the Ordos Basin and its coupling relationship with the peripheral tectonic belts,and further reveals the intrinsic connections and influencing factors of the energy resources in the basin.The conclusions are as follows:There are three large sedimentary hiatuses(Neoproterozoic-Early Cambrian,Late Ordovician-Early Carboniferous,and Late Cretaceous-Paleogene)and many small minor sedimentary hiatuses in the Ordos Block,which are mainly related to the tectonic activities,but also affected by the changes of the sea level and the climate.The Ordos Basin is a Meso-Cenozoic superposition basin formed by the contraction and reworking of the remnants of the Paleozoic cratonic basin,and its depositional extent and subsidence center have undergone multi-stage evolution,which was mainly influenced by the subduction of the Paleo-Pacific Plate.Influenced by the multi-directional convergence of peripheral plates in the North China Craton and the transformation of its own deep tectono-thermal regime,many coupled basin-mountain systems were formed with the Ordos Basin and the Yinshan orogenic belt,the Qinling orogenic belt,the Lvliangshan tectonic belt,the Helanshan tectonic belt or the Liupanshan tectonic belt as the core.The formation and enrichment of energy resources in the Ordos Basin are controlled by the tectono-sedimentary response,basin-mountain coupling evolution,and Early Cretaceous tectono-thermal events.All of them were gradually enriched into deposits during the formation,evolution,and reworking of the basin,and have a certain relationship of generation and coexistence,so they should belong to the same reservoir-forming(ore-forming)system.This study not only is helpful for revealing the coupling relationship between peripheral plate motions and internal mantle activities of the North China Craton,but also is of great significance for establishing the Earth's multi-layer coupling model and super energy system.展开更多
As important metal sulfides in the geochemical cycle of sulfur,the characteristics and formation processes of pyrites can provide useful clues regarding their environment.Based on previous findings,shale pyrites were ...As important metal sulfides in the geochemical cycle of sulfur,the characteristics and formation processes of pyrites can provide useful clues regarding their environment.Based on previous findings,shale pyrites were divided into three major classes(euhedral pyrites,framboidal pyrites(framboids)and metasomatic pyrites)and six sub-classes in this study.At the microscopic scale,each type of pyrite is associated with a different formation process.Framboids are formed by burst nucleation in environments with a homogeneous distribution of nutrients while euhedral pyrites are usually formed on pre-existing sites(such as=FeS on the minerals surface)in the heterogeneous system.Metasomatic pyrites formed by the replacement of other ions in accountable material by iron ions and hydrogen sulfide ions in hydrothermal events.The morphology and isotope value of pyrite provide information to track the origins of their nutrient and characteristics of sulfur and iron pools.In addition,the trace element content of pyrite can serve as a proxy for paleo-ocean trace element abundance,indicating changes in atmospheric oxygen content.Additionally,pyrite can also serves as an indicator of shale gas reservoirs.展开更多
基金supported by the Joint Funds of the National Natural Science Foundation of China(Grant No.U2341220)the Hefei Comprehensive National Science Center。
文摘This work proposes and fabricates the 4H-SiC power MOSFET with top oxide and double P-well(TODP-MOSFET)to enhance the single-event radiation tolerance of the gate oxide.Simulation results suggest that the proposed TODP structure reduces the peak electric field within the oxide and minimizes the sensitive region by more than 70%compared to C-MOSFETs.Experimental results show that the gate degradation voltage of the TODP-MOSFET is higher than that of the C-MOSFET,and the gate leakage current is reduced by 95%compared to the C-MOSFET under heavy-ion irradiation with a linear energy transfer(LET)value exceeding 75 MeV·cm^(2)/mg.
基金National Natural Science Foundation of China(No.32101150)Key Scientific Research Project of Higher Education of Henan Province(No.22A430007)+2 种基金Natural Science Foundation of Henan Province(No.222300420501)the Science and Technology Project of Henan Province(No.242102230119)Innovation and Entrepreneurship Training Program for College students in China(No.202310482001).
文摘Diseases associated with bacterial infection,especially those caused by gram-negative bacteria,have been posing a serious threat to human health.Photodynamic therapy based on aggregation-induced emission(AIE)photosensitizer have recently emerged and provided a promising approach for bacterial discrimination and efficient photodynamic antimicrobial applications.However,they often suffer from the shorter excitation wavelength and lower molar extinction coefficients in the visible region,severely limiting their further applications.Herein,three novel BF_(2)-curcuminoid-based AIE photosensitizers,TBBC,TBC and TBBC-C8,have been rationally designed and successfully developed,in which OCH_(3)-and OC_(8)H_(17)-substituted tetraphenylethene(TPE)groups serve as both electron donor(D)and AIE active moieties,BF_(2)bdk group functions as electron acceptor(A),and styrene(or ethylene)group asπ-bridge in this D-π-A-π-D system,respectively.As expected,these resulting BF_(2)-curcuminoids presented solvent-dependent photophysical properties with large molar extinction coefficients in solutions and excellent AIE properties.Notably,TBBC showed an effective singlet oxygen generation efficiency thanks to the smaller singlet-triplet energy gap(△E_(ST)),and remarkable photostability under green light exposure at 530nm(8.9 mW/cm^(2)).More importantly,TBBC was demonstrated effectiveness in selective staining and photodynamic killing of Escherichia coli(E.coli)in vitro probably due to its optimal molecular size compared with TBC and TBBC-C8.Therefore,TBBC will have great potential as a novel AIE photosensitizer to apply in the discrimination and selective sterilization between Gram-positive and Gram-negative bacteria.
基金funded by the PetroChina Major Research Program on Deep Petroleum System in the Tarim Basin(No.ZD 2019-183-01-003)the Major Research Project on the Tethys Geodynamic System from the National Natural Science Foundation of China(No.92055204)the National Natural Science Foundation of China(No.42072134).
文摘Determining the timing of fracturing is crucial for understanding reservoir evolution and hydrocarbon accumulation in foreland basins.Using fracturing data from cores,borehole images,and outcrops,combined with the clumped isotope(D47)and fluid inclusion analyses of carbonate minerals filled in pores and fractures,this study ascertained the fracturing timing of the Jurassic reservoirs in the Dibei-Tuziluoke Gas Field,Kuqa Foreland Basin.Data from outcrops and borehole images show two dominant fracture sets in the study area:W-E and NE-SW striking fractures.Some W-E striking fractures are carbonate-filled,while NE-SW striking fractures lack mineral fillings.Bitumen veins,not easy to be identified in borehole images,are prevalent in cores.The petrographic analysis reveals that these bitumen veins formed before the calcite cementation in pores and display high viscosity and low maturity.Homogenization temperatures(T_(h))from primary fluid inclusion assemblages in two representative calcite vein samples were notably lower than T_(△47) values from corresponding samples.This suggests the △_(47) signature underwent alteration due to partial reordering during burial.Thus,△_(47)-derived temperatures(apparent temperatures)may not faithfully represent the mineral precipitation temperatures.When plotting these apparent temperatures vs.the burial history,only the possible latest ages of fracturing emerged.These ages were further refined by considering petroleum charging,tectonic evolution,and stress orientation.Bitumen-filled fractures likely resulted from the Late Cretaceous uplift,marking the migration of low-maturity hydrocarbons in the study area.Carbonate-filled E-W striking fractures emerged during the late Miocene(~13-6.5 Ma)alongside fold development.NE-striking fractures that crosscut W-E ones possibly formed recently due to stress reorientation.
基金the Joint Fund of the National Natural Science Foundation of China under funding number of U19B6003-02-04the fund of A Theoretical Study of Marine Petroliferous System,Sichuan Basin,and the Science Foundation of China University of Petroleum,Beijing under funding number of 2462020BJRC005.
文摘The discovery and large-scale exploration of unconventional oil/gas resources since 1980s have been considered as the most important advancement in the history of petroleum geology;that has not only changed the balance of supply and demand in the global energy market,but also improved our understanding of the formation mechanisms and distribution characteristics of oil/gas reservoirs.However,what is the difference of conventional and unconventional resources and why they always related to each other in petroliferous basins is not clear.As the differences and correlations between unconventional and conventional resources are complex challenging issues and very critical for resources assessment and hydrocarbon exploration,this paper focused on studying the relationship of formations and distributions among different oil/gas reservoirs.Drilling results of 12,237 exploratory wells in 6 representative petroliferous basins of China and distribution characteristics for 52,926 oil/gas accumulations over the world were applied to clarify the formation conditions and genetic relations of different oil/gas reservoirs in a petroliferous basin,and then to establish a unified model to address the differences and correlations of conventional and unconventional reservoirs.In this model,conventional reservoirs formed in free hydrocarbon dynamic field with high porosity and permeability located above the boundary of hydrocarbon buoyancy-driven accumulation depth limit.Unconventional tight reservoirs formed in confined hydrocarbon dynamic field with low porosity and permeability located between hydrocarbon buoyancy-driven accumulation depth limit and hydrocarbon accumulation depth limit.Shale oil/gas reservoirs formed in the bound hydrocarbon dynamic field with low porosity and ultra-low permeability within the source rock layers.More than 75%of proved reserves around the world are discovered in the free hydrocarbon dynamic field,which is estimated to contain only 10%of originally generated hydrocarbons.Most of undiscovered resources distributed in the confined hydrocarbon dynamic field and the bound hydrocarbon dynamic field,which contains 90%of original generated hydrocarbons,implying a reasonable and promising area for future hydrocarbon explorations.The buried depths of hydrocarbon dynamic fields become shallow with the increase of heat flow,and the remaining oil/gas resources mainly exist in the deep area of“cold basin”with low geothermal gradient.Lithology changing in the hydrocarbon dynamic field causes local anomalies in the oil/gas dynamic mechanism,leading to the local formation of unconventional hydrocarbon reservoirs in the free hydrocarbon dynamic field or the occurrence of oil/gas enrichment sweet points with high porosity and permeability in the confined hydrocarbon dynamic field.The tectonic movements destroy the medium conditions and oil/gas components,which leads to the transformation of conventional oil/gas reservoirs formed in free hydrocarbon dynamic field to unconventional ones or unconventional ones formed in confined and bound hydrocarbon dynamic fields to conventional ones.
文摘Three dimensional (3D) microscopic distributions of dolomite and calcite in a limestone sample have been analyzed with a data-constrained modeling (DCM) technique using synchrotron radiation-based multi-energy X-ray computed tomography (CT) data as constraints. In order to optimize the experimental parameters, X-ray CT simulations and DCM analysis of a numerical phantom consisting of calcite (CaCO3) and dolomite (CaMg(CO3)2) have been used to investigate the effects on the predicted results in relation to noise, X-ray energy and sample-to-detector distance (SDD). The simulation results indicate that the optimal X-ray energies are 25 and 35 keVs, and the SDD is 10 mm. The high resolution 3D distributions of mineral phases of a natural limestone have been obtained. The results are useful for quantitative understanding of mineral, porosity, and physical property distributions in relation to oil and gas reservoirs hosted in carbonate rocks, which account for more than half of the world’s conventional hydrocarbon resources. The case studied is also instructive for the applicability of the DCM methods for other types of composite materials with modest atomic number contrasts between the mineral phases.
基金This study was supported by the Research Start-up Project for Introduced Talent of Yunnan University(No.20190043)the CNPC Key Laboratory of Carbonate Reservoirs Innovation Fund(No.RIPED-2020-JS-51020)。
文摘Recent decades have witnessed an increasing number of studies investigating petroleum systems with the application of rhenium-osmium(Re-Os) isotopic geochemistry. Here, we review the use of the 187 Re-187 Os geochronometer with respect to the geochemical behaviour of rhenium and osmium in hydrocarbon-related geological processes. The Re-Os budget in hydrocarbon source rock predominantly originates from natural water columns during its deposition. Open seawater tends to have a homogeneous Os isotopic composition because its residence time in seawater is longer than the time taken for ocean mixing. On the contrary, restricted water bodies(e.g., lakes) may have heterogeneous Os isotopic compositions due to the greater amount of terrigenous input. Hydrogenous Re and Os atoms are sequestered from the water body into sedimentary organic matter and transferred into crude oil through thermal maturation of organic matter. Thermal maturation likely does not significantly alter the Re-Os isotopic systematics of the source rock as a Re-Os isochron age of 442±21 Ma(2σ) is yielded in this study for over matured source rocks within the Silurian Longmaxi Formation from the Sichuan Basin. Re-Os atoms are mainly hosted by the highly polar/aggregating/aromatic asphaltenes in hydrocarbons, possibly chelating with organic complexes or occurring as metalloporphyrins. Resin and aromatic hydrocarbons also contribute to the Re-Os budget, but are 2 to 3 orders of magnitude lower than that of asphaltenes, whereas saturates do not contain appreciable Re-Os contents. The distribution of Re-Os atoms in hydrocarbons is heterogeneous because the duplicate analysis of pure single bitumen samples yields similar ^(187)Os/^(188)Os ratios whereas variable ^(187)Re/^(188)Os ratios. The Re-Os system in crude oils can be reset during transport away from the source rocks, with Os-rich organic fractions more readily expelled than Re-rich fractions. Contact with metal-rich fluids(e.g., hydrothermal fluid) or compositional changes related to asphaltene contents(e.g., deasphalting, biodegradation, thermal cracking and thermochemical sulphate reduction) are also likely to alter the Re-Os systematics in hydrocarbons. These geochemical features enable the ^(187)Re-^(187)Os isotopic system to have robust applicability for petroleum system investigations, which may use the Re-Os radiometric tool for:(1) stratigraphic correlation of source rocks,(2) dating geological events altering the asphaltene content in hydrocarbon such as hydrocarbon generation, thermochemical sulphate reduction, etc., and,(3) fingerprinting hydrocarbons. Regardless of the robustness of the ^(187)Re-^(187)Os geochronometer for petroleum system investigations, there are several pending questions such as partitioning between solid organic species or between organic matter and sulphide, chelating sites in hydrocarbons and Os isotopic equilibration between hydrocarbon subfractions. To improve the understanding of the Re-Os behaviour in petroleum systems, we underscore multi-proxies-based geochemistry(e.g., inorganic-organic geochemistry) and experimental studies(e.g., hydrous pyrolysis).
基金supported by the National Basic Research Program of China (2014CB239004)the ‘‘Element and Process Constraint Petroleum System Modeling’’ project (No. 2011A-0207) under the Petro China Science Innovation program
文摘Sorption isotherms of hydrocarbon and carbon dioxide （CO2） provide crucial information for designing processes to sequester CO2 and recover natural gas from unmineable coal beds. Methane （CH4）, ethane （C2H6）, and CO2 adsorption isotherms on dry coal and the temperature effect on their maximum sorption capacity have been studied by performing combined Monte Carlo （MC） and molecular dynamics （MD） simulations at temperatures of 308 and 370 K （35 and 97 ~C） and at pressures up to 10 MPa. Simulation results demonstrate that absolute sorption （expressed as a mass basis） divided by bulk gas density has negligible temperature effect on CH4, C2H6, and CO2 sorption on dry coal when pressure is over 6 MPa. CO2 is more closely packed due to stronger interaction with coal and the stronger interaction between CO2 mole- cules compared, respectively, with the interactions between hydrocarbons and coal and between hydrocarbons. The results of this work suggest that the ＂a＂ constant （pro- portional to TcPc） in the Peng-Robinson equation of state is an important factor affecting the sorption behavior of hydrocarbons. CO2 injection pressures of lower than 8 MPa may be desirable for CH4 recovery and CO2 sequestration. This study provides a quantitative under- standing of the effects of temperature on coal sorptioncapacity for CH4, C2H6, and CO2 from a microscopic perspective.
文摘An attempt is made in this paper to present the dynamics of the Eastern Niger Rift Basin (ENRB) with references to the key features and processes of petroleum systems based on published information. The Eastern Niger Basin is a superimposed rift basin with sedimentary structures emplaced during two rifts episodes. The Cretaceous episode is characterized by large, tilted normally faulted blocks trending NW-SE, that were reactivated in the Paleogene, while the Paleogene episode is characterized by normal faulted blocks that trend NNW-SSE. The rifting resulted in different basin structures with the north section dominated by asymmetric half-grabens while the south section is dominated by full-grabens. Three source rocks each belonging to three different play fairways exist: 1) The Paleogene Sokor-1 Member source belongs to second cycle syn-rift play associated with fluvial/deltaic facies;2) Cretaceous Yogou and Donga sources from first cycle post-rift play associated with alluvial/fluvial/deltaic and marine clastic and carbonate facies;and 3) Cretaceous Yogou source from first cycle transitional play associated with mudstone and shale of transitional facies. The ENRB comprises two source-reservoir-seal assemblages: a lower assemblage of Upper Cretaceous and an Upper assemblage of the Paleogene. Except for the Yogou source which possesses a self-contained petroleum system, the rest of the source rocks release their oils into the Paleogene Sokor-1 Member reservoir sealed regionally by the Oligocene Sokor-2 Member. The Paleogene assemblage is charged from the Upper Cretaceous Yogou Formation through fractures emplaced during the rifting episodes.
基金the National Natural Science Foundation of China(42172114,41772102 and 41402171)National Science Foundation of the United States(EAR 1620595)the China Scholarship Council(201706455043).
文摘Tectonic transition from a syn-rift stage to subsequent post-rift stage is an important mechanism in the evolution of extensional basins.The sedimentary infill records the crustal response to this process.We have obtained new detrital zircon U-Pb and Lu-Hf signatures from the Lower Cretaceous stratigraphic successions encompassing the commonly accepted syn-to post-rift transition boundary,the T4 unconformity,in the Songliao Basin,NE China.These constrain the Songliao Basin’s evolution from its center to distal margins,providing insights into the sediment provenance and dispersal pattern over the tectonic transition.Analysis of zircons from the syn-rift(the Shahezi and Yingcheng formations)and immediate post-rift(the Lower and Middle Denglouku Formation)stages reveals Phanerozoic age populations with positiveƐHf(t)values,which were derived from the proximal juvenile mantle-derived melt origin bedrocks of the Songliao Block.In contrast,the overlying samples from the Upper Denglouku Formation deposited in the subsequent post-rift stage contain exotic and ancient zircon populations with ages of 2.5 Ga&1.8 Ga and complex hafnium signatures,characteristic of a mixed origin.These are interpreted to be transported from distant cratonic terranes via larger drainage networks.It is obvious that the sediment dispersal pattern switched from being a local and hydrologically closed“intraregional”pattern to a“transcontinental”pattern during the transition.The time lag between the development of the T4 unconformity and the drainage reorganization also ensures a distinguishable3 Myr(106103 Ma,Late Albian)transition period of regional extent.During this transition stage,syn-rift faulting was replaced by postrift thermal subsidence,exhibiting a uniform sag configuration.Our new findings are important for understanding other continental rift basins during syn-to post-rift transition,which often demonstrates a complex interaction between the linkage and integration of sub-basins,and the reorganization of fluvial drainages and catchment systems.
基金supported by the National Natural Science Foundation of China(Grant Nos.42222208,42488101)。
文摘Feldspar minerals are widely present in clastic reservoirs of hydrocarbon-bearing basins,where they undergo significant dissolution during burial processes.The dissolution kinetics and evolutionary trends of feldspar under burial conditions are critical for the formation of secondary porosity and the evolution of reservoir spaces.The feldspar dissolution process is frequently associated with the precipitation and transformation of complex authigenic minerals,making it challenging to accurately determine dissolution rates under near-equilibrium conditions.This study performed experimental simulations of feldspar(K-feldspar and albite)dissolution under conditions ranging from far-from-equilibrium to near-equilibrium,with varying temperatures and pCO_(2).Under near-equilibrium conditions,scanning electron microscopy(SEM),energy-dispersive spectroscopy(EDS),and laser confocal microscopy were employed to achieve accurate quantification of the dissolution volume of feldspar samples.The dissolution rates of feldspar under near-equilibrium conditions,along with the factors influencing these rates,were systematically investigated.The results indicate that the dissolution rates of K-feldspar under near-equilibrium conditions at temperatures and pCO_(2)levels of 80℃/1 bar,120℃/4.2 bar,and 160℃/17.9 bar are 2.16695×10^(15)–8.040×10^(15),4.49288×10^(15)–1.480×10^(14),and 6.17462×10^(15)–2.496×10^(14)mol cm^(-2)s^(-1),respectively.Under the same near-equilibrium conditions,the dissolution rates of albite are 2.93294×10^(15)–1.365×10^(14),5.54499×10^(15)–2.170×10^(14),and 9.42841×10^(15)–3.074×10^(14)mol cm^(-2)s^(-1),respectively.The dissolution rates of feldspar under near-equilibrium conditions are significantly lower(1.5–2orders of magnitude at high temperatures)than those under far-equilibrium conditions.Furthermore,as the temperature increases by a gradient of 40℃,the dissolution rate only increases by only 1.5 times,which is substantially lower than the rate increase observed under far-equilibrium conditions.The discrepancy between feldspar dissolution rates under far-equilibrium conditions(L-TST)and near-equilibrium conditions increases with rising temperature.Under identical experimental conditions,the dissolution rate of albite under near-equilibrium conditions is higher than that of K-feldspar.The precipitation and transformation of secondary minerals regulate feldspar dissolution under near-equilibrium conditions by altering ion concentrations in the solution.The p H of the solution also plays a significant role in controlling feldspar dissolution under near-equilibrium conditions.This study establishes a method for quantitatively analyzing mineral dissolution using the surface morphological features of dissolved and undissolved segments of polished feldspar samples.This method avoids relying on changes in ion concentrations in the reaction solution,making it more reasonable and widely applicable.Moreover,the results provide valuable insights into feldspar dissolution kinetics under burial conditions within closed systems,enabling a more accurate assessment of the contribution of feldspar dissolution to pore formation in reservoirs.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFF0804300)the National Natural Science Foundation of China(Grant No.41530315)the National Science and Technology Major Project of China(Grant Nos.2016ZX05066,2017ZX05064)。
文摘Continental deformation on the Earth's surface is an extremely complex geological process,in which the formation and evolution of sedimentary basins are closely related to plate motions and mantle activities.Combining sedimentary basins with orogenic belts and sedimentary responses with tectonic activities can comprehensively elucidate the geological processes during the Earth's evolution.This paper focuses on the multi-stage evolution of the Ordos Basin,the coupled basin-mountain systems and energy resources,discusses the evolution of the Ordos Basin and its coupling relationship with the peripheral tectonic belts,and further reveals the intrinsic connections and influencing factors of the energy resources in the basin.The conclusions are as follows:There are three large sedimentary hiatuses(Neoproterozoic-Early Cambrian,Late Ordovician-Early Carboniferous,and Late Cretaceous-Paleogene)and many small minor sedimentary hiatuses in the Ordos Block,which are mainly related to the tectonic activities,but also affected by the changes of the sea level and the climate.The Ordos Basin is a Meso-Cenozoic superposition basin formed by the contraction and reworking of the remnants of the Paleozoic cratonic basin,and its depositional extent and subsidence center have undergone multi-stage evolution,which was mainly influenced by the subduction of the Paleo-Pacific Plate.Influenced by the multi-directional convergence of peripheral plates in the North China Craton and the transformation of its own deep tectono-thermal regime,many coupled basin-mountain systems were formed with the Ordos Basin and the Yinshan orogenic belt,the Qinling orogenic belt,the Lvliangshan tectonic belt,the Helanshan tectonic belt or the Liupanshan tectonic belt as the core.The formation and enrichment of energy resources in the Ordos Basin are controlled by the tectono-sedimentary response,basin-mountain coupling evolution,and Early Cretaceous tectono-thermal events.All of them were gradually enriched into deposits during the formation,evolution,and reworking of the basin,and have a certain relationship of generation and coexistence,so they should belong to the same reservoir-forming(ore-forming)system.This study not only is helpful for revealing the coupling relationship between peripheral plate motions and internal mantle activities of the North China Craton,but also is of great significance for establishing the Earth's multi-layer coupling model and super energy system.
基金supported by the National Natural Science Foundation of China(Grant Nos.42072164,42272119,41821002)the Shandong Provincial Key Research and Development Program,China(Grant No.2020ZLYS08)+1 种基金the Taishan Scholars Program,China(Grant No.TSQN201812030)the Fundamental Research Funds for the Central Universities,China(Grant No.2022CX06001A)。
文摘As important metal sulfides in the geochemical cycle of sulfur,the characteristics and formation processes of pyrites can provide useful clues regarding their environment.Based on previous findings,shale pyrites were divided into three major classes(euhedral pyrites,framboidal pyrites(framboids)and metasomatic pyrites)and six sub-classes in this study.At the microscopic scale,each type of pyrite is associated with a different formation process.Framboids are formed by burst nucleation in environments with a homogeneous distribution of nutrients while euhedral pyrites are usually formed on pre-existing sites(such as=FeS on the minerals surface)in the heterogeneous system.Metasomatic pyrites formed by the replacement of other ions in accountable material by iron ions and hydrogen sulfide ions in hydrothermal events.The morphology and isotope value of pyrite provide information to track the origins of their nutrient and characteristics of sulfur and iron pools.In addition,the trace element content of pyrite can serve as a proxy for paleo-ocean trace element abundance,indicating changes in atmospheric oxygen content.Additionally,pyrite can also serves as an indicator of shale gas reservoirs.
