The research on tectonization intensity plays an important role in the analyses of basin evolution and hydrocarbon accumulation. At present, methods in this field are almost qualitative, and the quantitative one is st...The research on tectonization intensity plays an important role in the analyses of basin evolution and hydrocarbon accumulation. At present, methods in this field are almost qualitative, and the quantitative one is still rarely reported. In this study, a quantitative research method for tectonization intensity is proposed. The research result on Tahe-Lunnan oilfield shows that this method can not only quantitatively express the tectonization intensity, but also qualitatively reflect the macroscopic deform property and the evolution history of strata. Therefore, it is an effective method for analyzing the characteristics of tectonization. In addition, the realization of the method also can provide qualitative information for studying the influence and control of tectonization on hydrocarbon accumulation.展开更多
This work makes the quantitative constrain on tectonizations of the Gangdese block, south Qinghai-Tibetan Plateau. Apatite fission track (AFT) dating analyses of 15 samples collected across the Gangdese block show tha...This work makes the quantitative constrain on tectonizations of the Gangdese block, south Qinghai-Tibetan Plateau. Apatite fission track (AFT) dating analyses of 15 samples collected across the Gangdese block show that the Gangdese block went through two periods of tectonizations, during -37.2-18.5 Ma and 18.5 - 8.0 Ma in the south Gangdese block, and during -47.6-5.3 Ma and 5.3-0 Ma in the middle Gangdese block. Different upliftings did not take place in the first period and rapid uplifting occurred in the late period. Meantime, there are some differences be-tween the south and middle Gangdese block. Their uplifting rate is 180 m/Ma and 70 m/Ma respectively. The rapid up-lifting time in the middle Gangdese block lagged behind the time in the south Gangdese block. It is Chala-Jiacuo-Riduo fault zone that is similar to the Yarlung Zangbo fault zone in control of the tectonization.展开更多
The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents t...The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents the integration of morphometric indices to quantitatively assess the spatial variation of tectonic activity along the AFZ.The AFZ is an active fault with both strike-slip and normal fault components and consists of two main branches,Mercimekdağı-Çamdere Fault(MÇF)and Tokat Fault(TF)segments.This study aims to assess the relative tectonic activity of the AFZ using various morphometric indices,based on a 10 m resolution DEM,with the aid of ArcGIS and MATLAB software.For this purpose,morphometric indices such as hypsometric integral(HI:0.35-0.65),mountain front sinuosity(Smf:1.3-1.44),valley floor width-height ratio(Vf:0.15-2.28),asymmetry factor(AF:23-77),drainage basin shape(Bs:1.13-6.10)and normalized steepness index(ksn:1-498)were applied to 53 drainage basins.When the Smf and mean Vf indices results were evaluated,it was calculated that the uplift ratio of the region was more than 0.5 mm/yr.The spatial distribution of the relative tectonic activity(Iat)of the area was revealed by combining the obtained morphometric indices analysis results.According to the Iat result,it was concluded that the MercimekdağıÇamdere Fault and Tokat Fault segments have high tectonic activity,but the Mercimekdağı-Çamdere Fault segment has higher tectonic activity.The results obtained were also confirmed by field observations.This research provides valuable information for the evaluation of tectonic activity in drainage systems controlled by splay faults.展开更多
By investigating the evolution of shale gas generation,storage,adjustment and accumulation under different structural settings in superimposed basins,this study elucidates the differential accumulation mechanisms of s...By investigating the evolution of shale gas generation,storage,adjustment and accumulation under different structural settings in superimposed basins,this study elucidates the differential accumulation mechanisms of shale gas.An improved evaluation method of shale gas content evolution in superimposed basins is proposed.This method incorporates the coupling effect of key geological factors such as temperature,pressure,organic matter abundance,maturity,and pore characteristics on the content and occurrence state of shale gas,as well as the configuration relationship between shale gas generation and storage throughout geological history.Using this approach,the gas evolution histories of the Longmaxi Formation shales in wells N201 and PY1 are reconstructed under varying geological conditions.The Longmaxi Formation shales in these wells are dominated by typeⅠkerogen,with original total organic carbon(TOC_(o))contents of 6.20 wt% and 4.92 wt%,respectively,indicating differences in the initial material basis for gas generation.At the maximum burial depth of approximately 5000 m,the Longmaxi Formation shale in well N201 exhibits a formation pressure coefficient of 2.05,an organic matter maturity of 2.2%,and organic pores accounting for 68%of the total porosity.The gas generation quantity(Q_(g))reaches 19.24 m^(3)/t,while the gas storage capacity(Q_(s))is 4.30 m^(3)/t.The actual total gas content(Q_(a)),constrained by Q_(s),is 4.30 m^(3)/t,with free gas comprising 94%.Following relatively moderate tectonic uplift,the Q_(a) in well N201 decreases to 4.03 m^(3)/t,with free gas accounting for 63%.In contrast,the Longmaxi Formation shale in well PY1 reached a maximum burial depth of 6300 m,associated with a formation pressure coefficient of 1.62,organic matter maturity of 2.5%,and organic pore proportion of 67%.Here,Q_(g) is 16.87 m^(3)/t,and both Q_(s) and Q_(a) are 3.65 m^(3)/t,with free gas accounting for 98%.After intense tectonic uplift,Q_(a) declines to 2.72 m^(3)/t,and the proportion of free gas drops to51%.Finally,a four-stage differential accumulation model of shale gas is established:Slow gas generation and only adsorbed gas occur in stageⅠ,which is primarily controlled by TOC content;both adsorbed gas and free gas present in stageⅡ,with free gas becoming dominant;rapid gas generation and free gas predominance are controlled by temperature and porosity in stageⅢ;and gas adjustment and accumulation are primarily controlled by temperature and pressure in stageⅣ.展开更多
Basement structures may influence how ruptures propagate during an earthquake.However,most structural evidence is beneath the thick layer of younger volcanic sediments.In this study,gravity method was applied to disco...Basement structures may influence how ruptures propagate during an earthquake.However,most structural evidence is beneath the thick layer of younger volcanic sediments.In this study,gravity method was applied to discover more features of the basement structure.A land survey of gravity measurement was conducted at 383 stations south of Toba.The observed gravity was then used to generate Complete Bouguer Anomaly and residual-regional anomaly maps.In addition,several edge enhancements based on derivations were applied.All results presented lineations that could be linked to previously recognized active faults and structures.Additionally,the most prominent feature is a large northwest-southeast elongated high anomaly,almost sub-parallel to the Sumatra Fault Zone(SFZ).Since the feature is also located at the continuation of the Medial Sumatra Tectonic Zone(MSTZ),the body might be the hidden part of this major tectonic zone.The occurrence of MSTZ across the SFZ would affect the rupture propagation of earthquake events in the fault segment of the SFZ.展开更多
Located in southern Ningxia Hui Autonomous Region,northwest China,the Liupan Mountain National Nature Reserve covers a total area of 26,783.64 hectares.Established in 1982 and upgraded to national status in 1988,it pr...Located in southern Ningxia Hui Autonomous Region,northwest China,the Liupan Mountain National Nature Reserve covers a total area of 26,783.64 hectares.Established in 1982 and upgraded to national status in 1988,it protects a vital temperate mountainous forest ecosystem on the Loess Plateau.The reserve is centred around the Liupan Mountain range,one of China’s youngest mountain chains,formed by Himalayan tectonic movements.展开更多
The transitional zone between the Sub-Himalaya and the Lesser Himalaya is delineated by the Main Boundary Thrust(MBT)to the north and the Himalayan Frontal Thrust(HFT)to the south.The MBT acts as a major topographic b...The transitional zone between the Sub-Himalaya and the Lesser Himalaya is delineated by the Main Boundary Thrust(MBT)to the north and the Himalayan Frontal Thrust(HFT)to the south.The MBT acts as a major topographic barrier that exerts significant control over longitudinal river valleys and sediment dispersal patterns.This region exhibits pronounced fluvial responses shaped by the interplay of tectonic activity and climatic processes.The present study addresses the need for detailed micro-scale morphometric analysis in this zone to better understand ongoing landscape deformation and neotectonic signatures.A multidisciplinary approach integrating geospatial morphometric techniques with field-based evidence has been employed to investigate terrain evolution.Quantitative morphometric assessments were conducted for 16 sub-basins within an active segment of the MBT,bounded by the Jakhan River to the east and the Giri River to the west.Dimensional changes driven by tectonic uplift and accelerated erosion/incision were evaluated using the hypsometric integral(HI),with most values falling below 0.50,indicating that the drainage basins are in an equilibrium stage.Basin shape(Bs)values range from 0.88 to 6.79,supporting the occurrence of accelerated erosional processes.The stream length gradient index(SL)exhibits values between 86 and 816,suggesting rapid uplift and incision.Similarly,computed values of the Chi(χ)coefficient(479-3706)and the steepness index(Ksn;63-214)reflect differential erosion and strong tectonic control on drainage network evolution.The spatial distribution of tectonic deformation was statistically evaluated using a correlation matrix based on the Relative Index of Active Tectonics(RIAT).The results reveal that approximately 50.33%and 16.25%of the study area fall into high and moderate activity zones,respectively,which is corroborated by historical earthquake records and geomorphic evidence.Neotectonic signatures are preserved in the landscape as river terraces,displaced or tilted strata,V-shaped valleys,river offsets,knickpoints,hanging valleys,and channel migration along the strike of the MBT.These findings underscore the significant role of neotectonics in landform evolution and offer valuable insights for geohazard assessment and mitigation strategies in the rapidly developing foothill regions of the Himalaya.展开更多
The available heat content (stored heat energy) of hot dry rock (HDR) at a depth of 1–10 km in the global land crust is estimated to be 5.06×10~8 EJ,attracting considerable global attention.This paper presents a...The available heat content (stored heat energy) of hot dry rock (HDR) at a depth of 1–10 km in the global land crust is estimated to be 5.06×10~8 EJ,attracting considerable global attention.This paper presents a comprehensive analysis of the geological framework,HDR resource potential,exploration advancements,and the development of enhanced geothermal systems (EGSs) in China.HDR resources are extensively distributed across China.Within the depth range of 3–10 km,China’s estimated potential approximates2.29×10~7 EJ,with a theoretical power generation capacity of approximately 1.67×10^(16) k Wh.Replacing coal power with HDR can help to achieve a net emission reduction of 1.34×10^(16) kg CO_(2) (approximately1.34×10^(13) t),representing an emission reduction efficiency of 94.4%.Based on a development cycle of100 years,the average annual emission reduction reaches 1.34×10^(10) t CO_(2),equivalent to 117%of China’s annual carbon emissions in 2022.Furthermore,in the context of global warming,the development and utilization of HDR,which is feasible in virtually any region worldwide,offers significant potential to support global carbon reduction efforts.China has made substantial progress in HDR exploration in recent years.This paper systematically classifies China’s HDR resources into four genetic types—highly radioactive heat-producing,sedimentary basin,active volcanic,and intensely tectonic zones—and offers detailed exploration insights for each category.Each classification exhibits distinct geological and tectonic characteristics that influence heat source mechanisms and resource distribution.Furthermore,this paper documents significant advances in EGS construction,particularly in the Gonghe Basin on the northeastern margin of the Qianghai-Xizang Plateau and the Matouying uplift in the North China Basin,where successful reservoir stimulation,microseismic monitoring,and experimental power generation have been achieved.Despite these developments,challenges persist,including technical adaptability under complex geological conditions and the economic viability of large-scale HDR development.This paper suggests that future initiatives should emphasize resource exploration,technological research,and policy support to foster sustainable HDR resource development in China,thereby contributing to the global energy transition and environmental sustainability.展开更多
How the subduction direction of the Paleo-Pacific plate beneath the Eurasian plate changes in the Early Cretaceous remains highly controversial due to the disappearance of the subducted oceanic plate.Intraplate deform...How the subduction direction of the Paleo-Pacific plate beneath the Eurasian plate changes in the Early Cretaceous remains highly controversial due to the disappearance of the subducted oceanic plate.Intraplate deformation structures in the east Asian continent,however,provide excellent opportunities for reconstructing paleostress fields in continental interior in relation to the Paleo-Pacific/Eurasian plate interaction.Anisotropy of magnetic susceptibility(AMS),geological,and geochronological analyses of post-kinematic mafic dykes intruding the detachment fault zone of the Wulian metamorphic core complex(WL MCC)in Jiaodong Peninsula exemplify emplacement of mantle-sourced dykes in a WNW-ESE(301°-121°)oriented tectonic extensional setting at ca.120 Ma.In combination with the results from our previous kinematic analysis of the MCC,a ca.21°clockwise change in the direction of intraplate extension is obtained for early(135-122 Ma)extensional exhumation of the MCC to late(122-108 Ma)emplacement of the dykes.Such a change is suggested to be related to the variation in subduction direction of the Paleo-Pacific plate beneath the Eurasian plate,from westward(pre-122 Ma)to west-northwestward(post-122 Ma).展开更多
The Ordos Basin(OB)in the western part of the North China Craton(NCC),was located at the jointed area of multi-plates and has recorded the Mesozoic tectonic characteristics.Its tectonic evolution in the Mesozoic is si...The Ordos Basin(OB)in the western part of the North China Craton(NCC),was located at the jointed area of multi-plates and has recorded the Mesozoic tectonic characteristics.Its tectonic evolution in the Mesozoic is significant to understand the tectonic transformation of the northern margin of the NCC.In this work,the detrital zircon and apatite(U-Th)/He chronological system were analyzed in the northern part of the OB,and have provided new evidence for the regional tectonic evolution.The(U-Th)/He chronological data states the weighted ages of 240‒235 Ma,141 Ma with the peak distribution of 244 Ma,219 Ma,173 Ma,147‒132 Ma.The thermal evolution,geochronological data,and regional unconformities have proved four stages of regional tectonic evolution for the OB and its surroundings in the Mesozoic:(1)The Late Permian-Early Triassic;(2)the Late Triassic-Early Jurassic;(3)the Late Jurassic-Early Cretaceous;(4)the Late Cretaceous-Early Paleogene.It is indicated that the multi-directional convergence from the surrounding tectonic units has controlled the Mesozoic tectonic evolution of the OB.Four-stage tectonic evolution reflected the activation or end of different plate movements and provided new time constraints for the regional tectonic evolution of the NCC in the Mesozoic.展开更多
The Cenozoic source-to-sink history of the Qaidam Basin is crucial for understanding of the basin-filling architecture,mountain-building processes and even the dynamics of the Tibetan Plateau growth.However,the proven...The Cenozoic source-to-sink history of the Qaidam Basin is crucial for understanding of the basin-filling architecture,mountain-building processes and even the dynamics of the Tibetan Plateau growth.However,the provenance history of Cenozoic strata in the Qaidam Basin remains ambiguous,especially in the northern Qaidam Basin.This controversy highlights the importance of obtaining the spatial source-to-sink relationships between the Qaidam Basin and its surrounding mountain ranges.In this study,we investigated the detrital zircon U-Pb ages of modern fluvial systems draining the East Kunlun Mountain.Their detrital zircon age distributions fall into five age groups:300-190,530-360,1000-560,2000-1100 and 2650-2000 Ma.The dominant age groups are 530-360 and 300-190 Ma,which represent the successive subduction of the Proto-Tethys and PaleoTethys Oceans and the subsequent continental collisions,respectively.Combining these new detrital zircon U-Pb ages with available age datasets,we finally obtained complete detrital zircon age information for modern fluvial systems in the whole Qaidam Basin.The U-Pb age distributions of modern river sands reveal that the zircon age signature of basement rocks in the East Kunlun Mountain is significantly different from that in the South Qilian Mountain but is similar to that in the Altyn Tagh Mountain.Moreover,these zircon age observations were confirmed by the significant difference in the Nd isotopic signature of modern river sands,which reveals a significant difference between the East Kunlun Mountain and South Qilian Mountain in the formation and evolution process.展开更多
The sedimentary geochemistry of St.Martin’s Island is important to determine the origin of the source rock,paleo weathering,tectonic setting,sediment recycling,maturity,sorting,redox condition,and paleo salinity of t...The sedimentary geochemistry of St.Martin’s Island is important to determine the origin of the source rock,paleo weathering,tectonic setting,sediment recycling,maturity,sorting,redox condition,and paleo salinity of the sediments.Major oxides,trace elements,and rare earth elements(REEs)obtained from the INAA technique are presented by analyzing the sediment samples collected from the shoreline of St.Martin’s Island,Bangladesh.The elemental ratios,comparison with average upper continental crust(UCC),binary diagrams(Th/Sc vs.Sc,La/Th vs.Hf,Th/Co vs.La/Sc),and chondrite normalized REE patterns exhibit substantial LREE enrichment,relatively fl at HREE fractionation,considerable negative Eu anomalies(average:0.72),indicates the derivation from a source dominated by felsic rock,with contribution from intermediate source and mafi c component.Sediments from St.Martin’s Island exhibit the deposition of sediments in transitional environments of active and passive continental margin settings.Weathering indices value of CIA,PIA,CIW,CIX,and K 2 O/Rb ratio show moderate chemical weathering,indicating that the sediments are chemically mature.Sedimentary redox indicative proxies,such as U/Th,V/Cr,and V/Sc,show an oxic depositional environment during sediment deposition.The intermediate CIA and other weathering index values of the St.Martin’s sediments show that the area had semiarid and humid climatic conditions throughout the deposition.The Rb/K ratio of the St.Martin’s sediments suggests that the development and deposition of the sedimentary sequence of St.Martin’s Island mainly occurred in a brackish water environment during the geological past.展开更多
In this article,the contemporary stress state of the Zhao-Ping metallogenic belt in eastern China was revealed using overcoring and hydraulic fracturing stress data,the relation between the stress field and geological...In this article,the contemporary stress state of the Zhao-Ping metallogenic belt in eastern China was revealed using overcoring and hydraulic fracturing stress data,the relation between the stress field and geological tectonics was discussed,and the stability of regional faults under the present-day stress environment was evaluated.The results indicate that the stress level is considerably high,and the distribution of stress intensity is uneven.The stress regime is primarily characterized by σ_(H)>σ_(v)>σ_(h).The σ_(H) orientation is well-oriented in the WNW-ESE,which is roughly identical to other stress indicators.Moreover,theσH direction reflected by joint strikes and inferred based on the fault characteristics agrees fairly with the identified stress orientation.The modern stress field basically inherited the tectonic stress field of the Yanshanian and Himalayan periods but is principally dominated by the Himalayan period.Additionally,the calculatedμm ranges from 0.2 to 0.7,indicating that the possibility of shallow faults across this area being reactivated and experiencing shear failure is small overall under the current stress conditions.μm=0.2 and 0.5 are suggested as the lower and upper limits for predicting and analyzing future fault activity in the area,respectively.展开更多
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
The BozdağHigh is a metamorphic core complex located between the Gediz(Alaşehir)and Küçük Menderes grabens in the Western Anatolia Extensional Province.The region is structurally controlled by low-angle...The BozdağHigh is a metamorphic core complex located between the Gediz(Alaşehir)and Küçük Menderes grabens in the Western Anatolia Extensional Province.The region is structurally controlled by low-angle Gediz Detachment Faults(GDF)and high-angle normal faults,which play a fundamental role in its geomorphological evolution.Understanding how these fault systems interact to shape uplift,drainage reorganization,and landscape dynamics remains an open scientific question.This study utilizes GIS-based morphometric analyses of 53 drainage basins and mountain fronts to quantify the spatial variations in uplift and fault activity.By integrating geomorphic indices(e.g.,χ-index,ksn,Smf,Vf)with analytical hierarchy process(AHP)models,we assess relative tectonic activity and investigate the kinematic evolution of fault-bounded blocks.Our findings reveal that the BozdağHigh experienced distinct rotational phases before and after the activation of high-angle faults,transitioning from an initial detachment-dominated extensional system to a segmented fault network.Additionally,BozdağHigh exhibits contrasting tectonic activity between its northern and southern flanks.While the northern flank,facing the Gediz Graben,experiences higher uplift rates and stronger tectonic forcing,the southern flank,adjacent to the Küçük Menderes Graben,exhibits relatively subdued tectonic activity and increased erosional modification.The western section of the eastern flank shows a more rapid uplift trend toward the east,whereas the southern flank displays significant surface tilting.Geomorphic evidence suggests that sequential fault activity and strain partitioning control differential uplift,drainage divide migrations,and basin asymmetry.Asymmetric basins in the southern sector,characterized by high hypsometric integral(HI)and low normalized steepness index(ksn)values,suggest a balance between erosional processes and tectonic uplift.In contrast,regions with ongoing rapid uplift exhibit higher ksn values and active knickpoint formation.These results provide new insights into the interaction between lowand high-angle fault systems and contribute to the broader understanding of tectonic evolution in extensional provinces.These new insights include the identification of spatially variable uplift and rotation patterns caused by sequential activation of low-and high-angle faults,revealing how block tilting and strain partitioning have shaped drainage reorganization and landscape evolution in the BozdağHigh.展开更多
Based on the detrital zircon U-Pb dating data,this paper discusses the provenance and constructs source-to-sink system of the Upper Jurassic in the North Yellow Sea Basin(NYSB),eastern North China Craton(ENCC).In addi...Based on the detrital zircon U-Pb dating data,this paper discusses the provenance and constructs source-to-sink system of the Upper Jurassic in the North Yellow Sea Basin(NYSB),eastern North China Craton(ENCC).In addition,to avoid the bias of detrital zircon ages caused by variations in zircon fertility,we collected 1709 whole rock zirconium content values(ppm)from granitic rocks with different ages in the North China Craton(NCC).Based on mean Zr content of granitic rocks in each age,these granitic rocks can be divided into four groups:Group A consists of Jurassic,Group B consists of Paleozoic,Neo-Mesoproterozoic and Neoarchean,Group C consists of Early Cretaceous and Triassic,and Group D consists of Paleoproterozoic.This research assigns to these groups zircon fertility factors(ZFF)of 1,1.4,1.8 and 2.2.The U-Pb age of detrital zircons from Late Jurassic sediments corrected by ZFF is statistically analyzed(K-S test,similarity,crosscorrelation,linkeness,and multidimensional scaling).And combining with paleocurrent and paleogeography,we construct two source-to-sink systems:(1)Jiaodong uplift and Sulu Orogenic Belt as the source area and the North Yellow Sea Basin as the sink area;(2)Liaodong Peninsula as the source area and the North Yellow Sea Basin as the sink area.展开更多
Since the Paleozoic,the tectonic evolution of northeastern Eurasia has been primarily influenced by the Paleo-Asian Ocean and the Paleo-Pacific tectonic domains.However,the spatial and temporal frameworks,as well as t...Since the Paleozoic,the tectonic evolution of northeastern Eurasia has been primarily influenced by the Paleo-Asian Ocean and the Paleo-Pacific tectonic domains.However,the spatial and temporal frameworks,as well as the timing of the tectonic transition between these two oceanic domains,remain unclear.For addressing these issues,we present petrological,geochronological,and geochemical data for andesite and sandstone samples from the Seluohe Group along the Jilin-Yanji Suture between the Jiamusi-Khanka Block and the North China Craton.The geochemical results indicate that the andesite sample is high-Mg andesite.Its magma source was generated by the metasomatized mantle wedge influenced by fluids derived from the subducted slab in a continental island arc setting.The high-Mg andesite gives the crystallization ages of Early Triassic(249±3 Ma).The sandstone is immature greywacke with a maximum depositional age of Early Triassic(247±1 Ma),and its sediments primarily originate from concurrent magmatic rocks within a juvenile continental arc.Based on our new findings,we propose that the Seluohe Group represents an Early Triassic volcanic-sedimentary association with continental island arc characteristics associated with the southwestward subduction of the Heilongjiang Ocean.We identified a sedimentary basin intimately associated with one or more continental arcs along the northeastern edge of the North China Craton.We suggest that the southwestward subduction of the Jilin-Heilongjiang Ocean in the Early Mesozoic accounts for this continental arc setting.There is a distinct temporal gap between the closure of the Paleo-Asian Ocean(ca.260 Ma)and the onset of Paleo-Pacific plate subduction(234–220 Ma),which is essentially coeval with the southwestward subduction of the Jilin-Heilongjiang Ocean between 255 Ma and 239 Ma.展开更多
1 Introduction The Maritime Silk Road, once a historic network of trade routes that connected continents and facilitated centuries of cultural and economic exchange, has become a region of profound scientific importan...1 Introduction The Maritime Silk Road, once a historic network of trade routes that connected continents and facilitated centuries of cultural and economic exchange, has become a region of profound scientific importance. Stretching from East Asia to Europe and Africa, its marine environments are among the most complex and dynamic on Earth. This region encompasses diverse geological settings, including tectonically active zones, varied sedimentary basins, and extensive continental shelves. These features make it a unique natural laboratory for studying various geological and geophysical processes.展开更多
The study of back-arc sedimentary basins is key to understanding oceanic and continental geodynamic processes and mechanisms.The East China Sea Shelf Basin(ECSSB),a back-arc sedimentary basin in a continent-ocean tran...The study of back-arc sedimentary basins is key to understanding oceanic and continental geodynamic processes and mechanisms.The East China Sea Shelf Basin(ECSSB),a back-arc sedimentary basin in a continent-ocean transition zone of the western Pacific Ocean,exhibits remarkable differences in terms of the tectonic deformation characteristics of the basin and the evolutionary features of its sags.These features have led to varied understandings of deep dynamic mechanisms driving the evolution of the basin.In this study,which is based on a detailed interpretation of two-dimensional multichannel seismic data from the ECSSB,the tectonic deformation of the basin is analyzed and the tectonic evolutionary process of the basin is reconstructed.The above research work combines plate convergence processes and deep crust-mantle interactions to explore the controlling factors and deep dynamic mechanisms of the tectonic deformation in the ECSSB.The results of this study indicate that there are significant differences in tectonic deformation between the southern and northern parts of the basin and that the deformation is characterized by eastward migration.Deep crust-mantle interactions are coupled with the development of these differences.The tectonic deformation of the ECSSB is driven by the interactions of the paleo-Pacific,Pacific,Indian,and Philippine Sea Plates with the Eurasian Plate,which have shaped the tectonic pattern of the ECSSB,resulting in east-west zoning,north-south blocking,and pronounced spatiotemporal variability in tectonic deformation.This research provides new insights into the differential development of sags within the ECSSB and provides an important reference for studying back-arc sedimentary basins.展开更多
Based on the analysis of surface geological survey,exploratory well,gravity-magnetic-electric and seismic data,and through mapping the sedimentary basin and its peripheral orogenic belts together,this paper explores s...Based on the analysis of surface geological survey,exploratory well,gravity-magnetic-electric and seismic data,and through mapping the sedimentary basin and its peripheral orogenic belts together,this paper explores systematically the boundary,distribution,geological structure,and tectonic attributes of the Ordos prototype basin in the geological historical periods.The results show that the Ordos block is bounded to the west by the Engorwusu Fault Zone,to the east by the Taihangshan Mountain Piedmont Fault Zone,to the north by the Solonker-Xilamuron Suture Zone,and to the south by the Shangnan-Danfeng Suture Zone.The Ordos Basin boundary was the plate tectonic boundary during the Middle Proterozoic to Paleozoic,and the intra-continental deformation boundary in the Meso-Cenozoic.The basin survived as a marine cratonic basin covering the entire Ordos block during the Middle Proterozoic to Ordovician,a marine-continental transitional depression basin enclosed by an island arc uplift belt at the plate margin during the Carboniferous to Permian,a unified intra-continental lacustrine depression basin in the Triassic,and an intra-continental cratonic basin circled by a rift system in the Cenozoic.The basin scope has been decreasing till the present.The large,widespread prototype basin controlled the exploration area far beyond the present-day sedimentary basin boundary,with multiple target plays vertically.The Ordos Basin has the characteristics of a whole petroleum(or deposition)system.The Middle Proterozoic wide-rift system as a typical basin under the overlying Phanerozoic basin and the Cambrian-Ordovician passive margin basin and intra-cratonic depression in the deep-sited basin will be the important successions for oil and gas exploration in the coming years.展开更多
基金Supported by China Postdoctoral Science Fund (Grant No.2012M510714)
文摘The research on tectonization intensity plays an important role in the analyses of basin evolution and hydrocarbon accumulation. At present, methods in this field are almost qualitative, and the quantitative one is still rarely reported. In this study, a quantitative research method for tectonization intensity is proposed. The research result on Tahe-Lunnan oilfield shows that this method can not only quantitatively express the tectonization intensity, but also qualitatively reflect the macroscopic deform property and the evolution history of strata. Therefore, it is an effective method for analyzing the characteristics of tectonization. In addition, the realization of the method also can provide qualitative information for studying the influence and control of tectonization on hydrocarbon accumulation.
基金This work was supported by the President Fund of the Chinese Academy of Sciences (CAS) (Grant No. 99-775) the National Natural Science Foundation of China (Grant No. 40072068) Laboratory of Nuclear Analysis Technique, the CAS.
文摘This work makes the quantitative constrain on tectonizations of the Gangdese block, south Qinghai-Tibetan Plateau. Apatite fission track (AFT) dating analyses of 15 samples collected across the Gangdese block show that the Gangdese block went through two periods of tectonizations, during -37.2-18.5 Ma and 18.5 - 8.0 Ma in the south Gangdese block, and during -47.6-5.3 Ma and 5.3-0 Ma in the middle Gangdese block. Different upliftings did not take place in the first period and rapid uplifting occurred in the late period. Meantime, there are some differences be-tween the south and middle Gangdese block. Their uplifting rate is 180 m/Ma and 70 m/Ma respectively. The rapid up-lifting time in the middle Gangdese block lagged behind the time in the south Gangdese block. It is Chala-Jiacuo-Riduo fault zone that is similar to the Yarlung Zangbo fault zone in control of the tectonization.
文摘The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents the integration of morphometric indices to quantitatively assess the spatial variation of tectonic activity along the AFZ.The AFZ is an active fault with both strike-slip and normal fault components and consists of two main branches,Mercimekdağı-Çamdere Fault(MÇF)and Tokat Fault(TF)segments.This study aims to assess the relative tectonic activity of the AFZ using various morphometric indices,based on a 10 m resolution DEM,with the aid of ArcGIS and MATLAB software.For this purpose,morphometric indices such as hypsometric integral(HI:0.35-0.65),mountain front sinuosity(Smf:1.3-1.44),valley floor width-height ratio(Vf:0.15-2.28),asymmetry factor(AF:23-77),drainage basin shape(Bs:1.13-6.10)and normalized steepness index(ksn:1-498)were applied to 53 drainage basins.When the Smf and mean Vf indices results were evaluated,it was calculated that the uplift ratio of the region was more than 0.5 mm/yr.The spatial distribution of the relative tectonic activity(Iat)of the area was revealed by combining the obtained morphometric indices analysis results.According to the Iat result,it was concluded that the MercimekdağıÇamdere Fault and Tokat Fault segments have high tectonic activity,but the Mercimekdağı-Çamdere Fault segment has higher tectonic activity.The results obtained were also confirmed by field observations.This research provides valuable information for the evaluation of tectonic activity in drainage systems controlled by splay faults.
基金funded by the Sinopec Science and Technology Project(No.P23132)the AAPG Foundation Grants-inAid Program(No.18644937)。
文摘By investigating the evolution of shale gas generation,storage,adjustment and accumulation under different structural settings in superimposed basins,this study elucidates the differential accumulation mechanisms of shale gas.An improved evaluation method of shale gas content evolution in superimposed basins is proposed.This method incorporates the coupling effect of key geological factors such as temperature,pressure,organic matter abundance,maturity,and pore characteristics on the content and occurrence state of shale gas,as well as the configuration relationship between shale gas generation and storage throughout geological history.Using this approach,the gas evolution histories of the Longmaxi Formation shales in wells N201 and PY1 are reconstructed under varying geological conditions.The Longmaxi Formation shales in these wells are dominated by typeⅠkerogen,with original total organic carbon(TOC_(o))contents of 6.20 wt% and 4.92 wt%,respectively,indicating differences in the initial material basis for gas generation.At the maximum burial depth of approximately 5000 m,the Longmaxi Formation shale in well N201 exhibits a formation pressure coefficient of 2.05,an organic matter maturity of 2.2%,and organic pores accounting for 68%of the total porosity.The gas generation quantity(Q_(g))reaches 19.24 m^(3)/t,while the gas storage capacity(Q_(s))is 4.30 m^(3)/t.The actual total gas content(Q_(a)),constrained by Q_(s),is 4.30 m^(3)/t,with free gas comprising 94%.Following relatively moderate tectonic uplift,the Q_(a) in well N201 decreases to 4.03 m^(3)/t,with free gas accounting for 63%.In contrast,the Longmaxi Formation shale in well PY1 reached a maximum burial depth of 6300 m,associated with a formation pressure coefficient of 1.62,organic matter maturity of 2.5%,and organic pore proportion of 67%.Here,Q_(g) is 16.87 m^(3)/t,and both Q_(s) and Q_(a) are 3.65 m^(3)/t,with free gas accounting for 98%.After intense tectonic uplift,Q_(a) declines to 2.72 m^(3)/t,and the proportion of free gas drops to51%.Finally,a four-stage differential accumulation model of shale gas is established:Slow gas generation and only adsorbed gas occur in stageⅠ,which is primarily controlled by TOC content;both adsorbed gas and free gas present in stageⅡ,with free gas becoming dominant;rapid gas generation and free gas predominance are controlled by temperature and porosity in stageⅢ;and gas adjustment and accumulation are primarily controlled by temperature and pressure in stageⅣ.
基金National Research and Innovation Agency(BRIN),Indonesia,with Grant No.373/II/FR/3/2022(Expedition and Exploration Fund)and 676/III/PR.01.December 03,2021(Geological Hazard In-House Program)。
文摘Basement structures may influence how ruptures propagate during an earthquake.However,most structural evidence is beneath the thick layer of younger volcanic sediments.In this study,gravity method was applied to discover more features of the basement structure.A land survey of gravity measurement was conducted at 383 stations south of Toba.The observed gravity was then used to generate Complete Bouguer Anomaly and residual-regional anomaly maps.In addition,several edge enhancements based on derivations were applied.All results presented lineations that could be linked to previously recognized active faults and structures.Additionally,the most prominent feature is a large northwest-southeast elongated high anomaly,almost sub-parallel to the Sumatra Fault Zone(SFZ).Since the feature is also located at the continuation of the Medial Sumatra Tectonic Zone(MSTZ),the body might be the hidden part of this major tectonic zone.The occurrence of MSTZ across the SFZ would affect the rupture propagation of earthquake events in the fault segment of the SFZ.
文摘Located in southern Ningxia Hui Autonomous Region,northwest China,the Liupan Mountain National Nature Reserve covers a total area of 26,783.64 hectares.Established in 1982 and upgraded to national status in 1988,it protects a vital temperate mountainous forest ecosystem on the Loess Plateau.The reserve is centred around the Liupan Mountain range,one of China’s youngest mountain chains,formed by Himalayan tectonic movements.
基金Department of Petroleum Engineering and Earth Sciences,UPES,for supporting this researchR&D,UPES,for providing a PhD scholarship and contingency to support geological fieldworkDST-ANRF Grant no CRG/2023/000555 for partial financial support for this research.
文摘The transitional zone between the Sub-Himalaya and the Lesser Himalaya is delineated by the Main Boundary Thrust(MBT)to the north and the Himalayan Frontal Thrust(HFT)to the south.The MBT acts as a major topographic barrier that exerts significant control over longitudinal river valleys and sediment dispersal patterns.This region exhibits pronounced fluvial responses shaped by the interplay of tectonic activity and climatic processes.The present study addresses the need for detailed micro-scale morphometric analysis in this zone to better understand ongoing landscape deformation and neotectonic signatures.A multidisciplinary approach integrating geospatial morphometric techniques with field-based evidence has been employed to investigate terrain evolution.Quantitative morphometric assessments were conducted for 16 sub-basins within an active segment of the MBT,bounded by the Jakhan River to the east and the Giri River to the west.Dimensional changes driven by tectonic uplift and accelerated erosion/incision were evaluated using the hypsometric integral(HI),with most values falling below 0.50,indicating that the drainage basins are in an equilibrium stage.Basin shape(Bs)values range from 0.88 to 6.79,supporting the occurrence of accelerated erosional processes.The stream length gradient index(SL)exhibits values between 86 and 816,suggesting rapid uplift and incision.Similarly,computed values of the Chi(χ)coefficient(479-3706)and the steepness index(Ksn;63-214)reflect differential erosion and strong tectonic control on drainage network evolution.The spatial distribution of tectonic deformation was statistically evaluated using a correlation matrix based on the Relative Index of Active Tectonics(RIAT).The results reveal that approximately 50.33%and 16.25%of the study area fall into high and moderate activity zones,respectively,which is corroborated by historical earthquake records and geomorphic evidence.Neotectonic signatures are preserved in the landscape as river terraces,displaced or tilted strata,V-shaped valleys,river offsets,knickpoints,hanging valleys,and channel migration along the strike of the MBT.These findings underscore the significant role of neotectonics in landform evolution and offer valuable insights for geohazard assessment and mitigation strategies in the rapidly developing foothill regions of the Himalaya.
基金supported by the National Key Research and Development Program of China (2021YFB1507401)Qinghai Province Clean Energy Minerals Special Project(2022013004qj004)Geological Survey Project of China Geological Survey (DD20221676, DD20230019)。
文摘The available heat content (stored heat energy) of hot dry rock (HDR) at a depth of 1–10 km in the global land crust is estimated to be 5.06×10~8 EJ,attracting considerable global attention.This paper presents a comprehensive analysis of the geological framework,HDR resource potential,exploration advancements,and the development of enhanced geothermal systems (EGSs) in China.HDR resources are extensively distributed across China.Within the depth range of 3–10 km,China’s estimated potential approximates2.29×10~7 EJ,with a theoretical power generation capacity of approximately 1.67×10^(16) k Wh.Replacing coal power with HDR can help to achieve a net emission reduction of 1.34×10^(16) kg CO_(2) (approximately1.34×10^(13) t),representing an emission reduction efficiency of 94.4%.Based on a development cycle of100 years,the average annual emission reduction reaches 1.34×10^(10) t CO_(2),equivalent to 117%of China’s annual carbon emissions in 2022.Furthermore,in the context of global warming,the development and utilization of HDR,which is feasible in virtually any region worldwide,offers significant potential to support global carbon reduction efforts.China has made substantial progress in HDR exploration in recent years.This paper systematically classifies China’s HDR resources into four genetic types—highly radioactive heat-producing,sedimentary basin,active volcanic,and intensely tectonic zones—and offers detailed exploration insights for each category.Each classification exhibits distinct geological and tectonic characteristics that influence heat source mechanisms and resource distribution.Furthermore,this paper documents significant advances in EGS construction,particularly in the Gonghe Basin on the northeastern margin of the Qianghai-Xizang Plateau and the Matouying uplift in the North China Basin,where successful reservoir stimulation,microseismic monitoring,and experimental power generation have been achieved.Despite these developments,challenges persist,including technical adaptability under complex geological conditions and the economic viability of large-scale HDR development.This paper suggests that future initiatives should emphasize resource exploration,technological research,and policy support to foster sustainable HDR resource development in China,thereby contributing to the global energy transition and environmental sustainability.
基金supported by the National Natural Science Foundation of China(Grant Nos:42130801,41430211,90814006,and 42072226)the“Deep-time Digital Earth”Science and Technology Leading Talents Team Funds for the Central Universities for the Frontiers Science Center for Deep-time Digital Earth,CUGB(Fundamental Research Funds for the Central UniversitiesGrant No:2652023001).
文摘How the subduction direction of the Paleo-Pacific plate beneath the Eurasian plate changes in the Early Cretaceous remains highly controversial due to the disappearance of the subducted oceanic plate.Intraplate deformation structures in the east Asian continent,however,provide excellent opportunities for reconstructing paleostress fields in continental interior in relation to the Paleo-Pacific/Eurasian plate interaction.Anisotropy of magnetic susceptibility(AMS),geological,and geochronological analyses of post-kinematic mafic dykes intruding the detachment fault zone of the Wulian metamorphic core complex(WL MCC)in Jiaodong Peninsula exemplify emplacement of mantle-sourced dykes in a WNW-ESE(301°-121°)oriented tectonic extensional setting at ca.120 Ma.In combination with the results from our previous kinematic analysis of the MCC,a ca.21°clockwise change in the direction of intraplate extension is obtained for early(135-122 Ma)extensional exhumation of the MCC to late(122-108 Ma)emplacement of the dykes.Such a change is suggested to be related to the variation in subduction direction of the Paleo-Pacific plate beneath the Eurasian plate,from westward(pre-122 Ma)to west-northwestward(post-122 Ma).
基金This study was jointly supported by the Science&Technology Fundamental Resources Investigation Program(2022FY101800)National Science Foundation(92162212)+1 种基金the project from the Key Laboratory of Tectonics and Petroleum Resources(China University of Geosciences,Wuhan)(TPR-2022-22)the International Geoscience Programme(IGCP-675)。
文摘The Ordos Basin(OB)in the western part of the North China Craton(NCC),was located at the jointed area of multi-plates and has recorded the Mesozoic tectonic characteristics.Its tectonic evolution in the Mesozoic is significant to understand the tectonic transformation of the northern margin of the NCC.In this work,the detrital zircon and apatite(U-Th)/He chronological system were analyzed in the northern part of the OB,and have provided new evidence for the regional tectonic evolution.The(U-Th)/He chronological data states the weighted ages of 240‒235 Ma,141 Ma with the peak distribution of 244 Ma,219 Ma,173 Ma,147‒132 Ma.The thermal evolution,geochronological data,and regional unconformities have proved four stages of regional tectonic evolution for the OB and its surroundings in the Mesozoic:(1)The Late Permian-Early Triassic;(2)the Late Triassic-Early Jurassic;(3)the Late Jurassic-Early Cretaceous;(4)the Late Cretaceous-Early Paleogene.It is indicated that the multi-directional convergence from the surrounding tectonic units has controlled the Mesozoic tectonic evolution of the OB.Four-stage tectonic evolution reflected the activation or end of different plate movements and provided new time constraints for the regional tectonic evolution of the NCC in the Mesozoic.
基金supported by the Geological Survey of China(No.DD20221645)the National Natural Science Foundation of China(Nos.42171010,42072141,41702118)。
文摘The Cenozoic source-to-sink history of the Qaidam Basin is crucial for understanding of the basin-filling architecture,mountain-building processes and even the dynamics of the Tibetan Plateau growth.However,the provenance history of Cenozoic strata in the Qaidam Basin remains ambiguous,especially in the northern Qaidam Basin.This controversy highlights the importance of obtaining the spatial source-to-sink relationships between the Qaidam Basin and its surrounding mountain ranges.In this study,we investigated the detrital zircon U-Pb ages of modern fluvial systems draining the East Kunlun Mountain.Their detrital zircon age distributions fall into five age groups:300-190,530-360,1000-560,2000-1100 and 2650-2000 Ma.The dominant age groups are 530-360 and 300-190 Ma,which represent the successive subduction of the Proto-Tethys and PaleoTethys Oceans and the subsequent continental collisions,respectively.Combining these new detrital zircon U-Pb ages with available age datasets,we finally obtained complete detrital zircon age information for modern fluvial systems in the whole Qaidam Basin.The U-Pb age distributions of modern river sands reveal that the zircon age signature of basement rocks in the East Kunlun Mountain is significantly different from that in the South Qilian Mountain but is similar to that in the Altyn Tagh Mountain.Moreover,these zircon age observations were confirmed by the significant difference in the Nd isotopic signature of modern river sands,which reveals a significant difference between the East Kunlun Mountain and South Qilian Mountain in the formation and evolution process.
基金Supporting Program for funding this work under Project number(RSP2024R328),King Saud University,Riyadh,Saudi Arabia.
文摘The sedimentary geochemistry of St.Martin’s Island is important to determine the origin of the source rock,paleo weathering,tectonic setting,sediment recycling,maturity,sorting,redox condition,and paleo salinity of the sediments.Major oxides,trace elements,and rare earth elements(REEs)obtained from the INAA technique are presented by analyzing the sediment samples collected from the shoreline of St.Martin’s Island,Bangladesh.The elemental ratios,comparison with average upper continental crust(UCC),binary diagrams(Th/Sc vs.Sc,La/Th vs.Hf,Th/Co vs.La/Sc),and chondrite normalized REE patterns exhibit substantial LREE enrichment,relatively fl at HREE fractionation,considerable negative Eu anomalies(average:0.72),indicates the derivation from a source dominated by felsic rock,with contribution from intermediate source and mafi c component.Sediments from St.Martin’s Island exhibit the deposition of sediments in transitional environments of active and passive continental margin settings.Weathering indices value of CIA,PIA,CIW,CIX,and K 2 O/Rb ratio show moderate chemical weathering,indicating that the sediments are chemically mature.Sedimentary redox indicative proxies,such as U/Th,V/Cr,and V/Sc,show an oxic depositional environment during sediment deposition.The intermediate CIA and other weathering index values of the St.Martin’s sediments show that the area had semiarid and humid climatic conditions throughout the deposition.The Rb/K ratio of the St.Martin’s sediments suggests that the development and deposition of the sedimentary sequence of St.Martin’s Island mainly occurred in a brackish water environment during the geological past.
基金supported by the National Natural Science Foundation of China(52204084)the Open Research Fund of The State Key Laboratory of Coal Resources and safe Mining,CUMT(SKLCRSM23KF004)+3 种基金the Interdisciplinary Research Project for Young Teachers of USTB(Fundamental Research Funds for the Central Universities)(FRF-IDRY-GD22-002)the Fundamen〓〓tal Research Funds for the Central Universities and the Youth Teacher International Exchange and Growth Program(QNXM20220009)the National Key R&D Program of China(2022YFC2905600 and 2022YFC3004601)the Science,Technology&Innovation Proj〓〓ect of Xiongan New Area(2023XAGG0061).
文摘In this article,the contemporary stress state of the Zhao-Ping metallogenic belt in eastern China was revealed using overcoring and hydraulic fracturing stress data,the relation between the stress field and geological tectonics was discussed,and the stability of regional faults under the present-day stress environment was evaluated.The results indicate that the stress level is considerably high,and the distribution of stress intensity is uneven.The stress regime is primarily characterized by σ_(H)>σ_(v)>σ_(h).The σ_(H) orientation is well-oriented in the WNW-ESE,which is roughly identical to other stress indicators.Moreover,theσH direction reflected by joint strikes and inferred based on the fault characteristics agrees fairly with the identified stress orientation.The modern stress field basically inherited the tectonic stress field of the Yanshanian and Himalayan periods but is principally dominated by the Himalayan period.Additionally,the calculatedμm ranges from 0.2 to 0.7,indicating that the possibility of shallow faults across this area being reactivated and experiencing shear failure is small overall under the current stress conditions.μm=0.2 and 0.5 are suggested as the lower and upper limits for predicting and analyzing future fault activity in the area,respectively.
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.
文摘The BozdağHigh is a metamorphic core complex located between the Gediz(Alaşehir)and Küçük Menderes grabens in the Western Anatolia Extensional Province.The region is structurally controlled by low-angle Gediz Detachment Faults(GDF)and high-angle normal faults,which play a fundamental role in its geomorphological evolution.Understanding how these fault systems interact to shape uplift,drainage reorganization,and landscape dynamics remains an open scientific question.This study utilizes GIS-based morphometric analyses of 53 drainage basins and mountain fronts to quantify the spatial variations in uplift and fault activity.By integrating geomorphic indices(e.g.,χ-index,ksn,Smf,Vf)with analytical hierarchy process(AHP)models,we assess relative tectonic activity and investigate the kinematic evolution of fault-bounded blocks.Our findings reveal that the BozdağHigh experienced distinct rotational phases before and after the activation of high-angle faults,transitioning from an initial detachment-dominated extensional system to a segmented fault network.Additionally,BozdağHigh exhibits contrasting tectonic activity between its northern and southern flanks.While the northern flank,facing the Gediz Graben,experiences higher uplift rates and stronger tectonic forcing,the southern flank,adjacent to the Küçük Menderes Graben,exhibits relatively subdued tectonic activity and increased erosional modification.The western section of the eastern flank shows a more rapid uplift trend toward the east,whereas the southern flank displays significant surface tilting.Geomorphic evidence suggests that sequential fault activity and strain partitioning control differential uplift,drainage divide migrations,and basin asymmetry.Asymmetric basins in the southern sector,characterized by high hypsometric integral(HI)and low normalized steepness index(ksn)values,suggest a balance between erosional processes and tectonic uplift.In contrast,regions with ongoing rapid uplift exhibit higher ksn values and active knickpoint formation.These results provide new insights into the interaction between lowand high-angle fault systems and contribute to the broader understanding of tectonic evolution in extensional provinces.These new insights include the identification of spatially variable uplift and rotation patterns caused by sequential activation of low-and high-angle faults,revealing how block tilting and strain partitioning have shaped drainage reorganization and landscape evolution in the BozdağHigh.
基金supported by the National Natural Science Foundation of China(Nos.41872101 and 41790453-4)。
文摘Based on the detrital zircon U-Pb dating data,this paper discusses the provenance and constructs source-to-sink system of the Upper Jurassic in the North Yellow Sea Basin(NYSB),eastern North China Craton(ENCC).In addition,to avoid the bias of detrital zircon ages caused by variations in zircon fertility,we collected 1709 whole rock zirconium content values(ppm)from granitic rocks with different ages in the North China Craton(NCC).Based on mean Zr content of granitic rocks in each age,these granitic rocks can be divided into four groups:Group A consists of Jurassic,Group B consists of Paleozoic,Neo-Mesoproterozoic and Neoarchean,Group C consists of Early Cretaceous and Triassic,and Group D consists of Paleoproterozoic.This research assigns to these groups zircon fertility factors(ZFF)of 1,1.4,1.8 and 2.2.The U-Pb age of detrital zircons from Late Jurassic sediments corrected by ZFF is statistically analyzed(K-S test,similarity,crosscorrelation,linkeness,and multidimensional scaling).And combining with paleocurrent and paleogeography,we construct two source-to-sink systems:(1)Jiaodong uplift and Sulu Orogenic Belt as the source area and the North Yellow Sea Basin as the sink area;(2)Liaodong Peninsula as the source area and the North Yellow Sea Basin as the sink area.
基金Supported by the National Natural Science Foundation of China Nos.42230303,42430305 and 42302236Graduate Innovation Fund of Jilin University Number:2024CX109.
文摘Since the Paleozoic,the tectonic evolution of northeastern Eurasia has been primarily influenced by the Paleo-Asian Ocean and the Paleo-Pacific tectonic domains.However,the spatial and temporal frameworks,as well as the timing of the tectonic transition between these two oceanic domains,remain unclear.For addressing these issues,we present petrological,geochronological,and geochemical data for andesite and sandstone samples from the Seluohe Group along the Jilin-Yanji Suture between the Jiamusi-Khanka Block and the North China Craton.The geochemical results indicate that the andesite sample is high-Mg andesite.Its magma source was generated by the metasomatized mantle wedge influenced by fluids derived from the subducted slab in a continental island arc setting.The high-Mg andesite gives the crystallization ages of Early Triassic(249±3 Ma).The sandstone is immature greywacke with a maximum depositional age of Early Triassic(247±1 Ma),and its sediments primarily originate from concurrent magmatic rocks within a juvenile continental arc.Based on our new findings,we propose that the Seluohe Group represents an Early Triassic volcanic-sedimentary association with continental island arc characteristics associated with the southwestward subduction of the Heilongjiang Ocean.We identified a sedimentary basin intimately associated with one or more continental arcs along the northeastern edge of the North China Craton.We suggest that the southwestward subduction of the Jilin-Heilongjiang Ocean in the Early Mesozoic accounts for this continental arc setting.There is a distinct temporal gap between the closure of the Paleo-Asian Ocean(ca.260 Ma)and the onset of Paleo-Pacific plate subduction(234–220 Ma),which is essentially coeval with the southwestward subduction of the Jilin-Heilongjiang Ocean between 255 Ma and 239 Ma.
文摘1 Introduction The Maritime Silk Road, once a historic network of trade routes that connected continents and facilitated centuries of cultural and economic exchange, has become a region of profound scientific importance. Stretching from East Asia to Europe and Africa, its marine environments are among the most complex and dynamic on Earth. This region encompasses diverse geological settings, including tectonically active zones, varied sedimentary basins, and extensive continental shelves. These features make it a unique natural laboratory for studying various geological and geophysical processes.
基金the Laoshan Laboratory(No.LSKJ202203401)the Geological Survey Projects of the China Geological Survey(Nos.DD20221723,DD20243116)+2 种基金the Natural Science Foundation of Shandong Province(No.ZR2023MD047)the Major Basic Research Project of Shandong Province(No.ZR2021ZD09)the National Natural Science Foundation of China(No.42476077)。
文摘The study of back-arc sedimentary basins is key to understanding oceanic and continental geodynamic processes and mechanisms.The East China Sea Shelf Basin(ECSSB),a back-arc sedimentary basin in a continent-ocean transition zone of the western Pacific Ocean,exhibits remarkable differences in terms of the tectonic deformation characteristics of the basin and the evolutionary features of its sags.These features have led to varied understandings of deep dynamic mechanisms driving the evolution of the basin.In this study,which is based on a detailed interpretation of two-dimensional multichannel seismic data from the ECSSB,the tectonic deformation of the basin is analyzed and the tectonic evolutionary process of the basin is reconstructed.The above research work combines plate convergence processes and deep crust-mantle interactions to explore the controlling factors and deep dynamic mechanisms of the tectonic deformation in the ECSSB.The results of this study indicate that there are significant differences in tectonic deformation between the southern and northern parts of the basin and that the deformation is characterized by eastward migration.Deep crust-mantle interactions are coupled with the development of these differences.The tectonic deformation of the ECSSB is driven by the interactions of the paleo-Pacific,Pacific,Indian,and Philippine Sea Plates with the Eurasian Plate,which have shaped the tectonic pattern of the ECSSB,resulting in east-west zoning,north-south blocking,and pronounced spatiotemporal variability in tectonic deformation.This research provides new insights into the differential development of sags within the ECSSB and provides an important reference for studying back-arc sedimentary basins.
基金Supported by the National Natural Science Foundation of China(42330810)Major Science and Technology Project of PetroChina Changqing Oilfield Company(ZDZX2021-01).
文摘Based on the analysis of surface geological survey,exploratory well,gravity-magnetic-electric and seismic data,and through mapping the sedimentary basin and its peripheral orogenic belts together,this paper explores systematically the boundary,distribution,geological structure,and tectonic attributes of the Ordos prototype basin in the geological historical periods.The results show that the Ordos block is bounded to the west by the Engorwusu Fault Zone,to the east by the Taihangshan Mountain Piedmont Fault Zone,to the north by the Solonker-Xilamuron Suture Zone,and to the south by the Shangnan-Danfeng Suture Zone.The Ordos Basin boundary was the plate tectonic boundary during the Middle Proterozoic to Paleozoic,and the intra-continental deformation boundary in the Meso-Cenozoic.The basin survived as a marine cratonic basin covering the entire Ordos block during the Middle Proterozoic to Ordovician,a marine-continental transitional depression basin enclosed by an island arc uplift belt at the plate margin during the Carboniferous to Permian,a unified intra-continental lacustrine depression basin in the Triassic,and an intra-continental cratonic basin circled by a rift system in the Cenozoic.The basin scope has been decreasing till the present.The large,widespread prototype basin controlled the exploration area far beyond the present-day sedimentary basin boundary,with multiple target plays vertically.The Ordos Basin has the characteristics of a whole petroleum(or deposition)system.The Middle Proterozoic wide-rift system as a typical basin under the overlying Phanerozoic basin and the Cambrian-Ordovician passive margin basin and intra-cratonic depression in the deep-sited basin will be the important successions for oil and gas exploration in the coming years.
