Based on the ArcGIS geographic information system and the ORACLE database management system,this paper reports our studies on the technology of Marine Engineering Geological Exploration Information System(MEGEIS). By ...Based on the ArcGIS geographic information system and the ORACLE database management system,this paper reports our studies on the technology of Marine Engineering Geological Exploration Information System(MEGEIS). By analyzing system structure,designing function modules and discussing data management,this paper systematically proposes a framework of technol-ogy to integrate,manage,and analyze the seabed information comprehensively. Then,the technology is applied to the design and development of the Bohai Sea Oilfield Paradigm Area Information System. The system can not only meet the practical demands of marine resources exploration and exploitation in the Bohai Sea oilfield,but also serve as a preparatory work in theory and technology for the realization of the 'Digital Seabed'.展开更多
In recent years, based on the rapid development of our country's social economy, the utilization of geological and mineral resources is also increasing, and its mining will directly affect the sustainable developm...In recent years, based on the rapid development of our country's social economy, the utilization of geological and mineral resources is also increasing, and its mining will directly affect the sustainable development of our country's economic construction, so in order to meet the market demand, geological exploration technology needs to keep pace with the times, and constantly carry out reform and optimization. In the actual mining work, the application of geological exploration technology can greatly improve its work efficiency. However, its safety cannot be ignored, it will directly affect the development of geological exploration. All along, our country has abundant mineral resources, which can effectively promote the improvement of our country's social and economic level. Mineral resources are non-renewable energy, so the best exploration technology should be used in the mining and use of mineral resources, so as to achieve the purpose of orderly development of the whole work.展开更多
A high efficiency method is very important in geological survey for a new city in China.Geophysical parameters are Measured While Drilling(MWD),and these parameters are processed and explained on the ground,so the met...A high efficiency method is very important in geological survey for a new city in China.Geophysical parameters are Measured While Drilling(MWD),and these parameters are processed and explained on the ground,so the method can replace conventional engineering geological exploration for drilling rock sample.According petroleum engineering MWD,using the different characters of different rock absorbs γ radial,with the method of storing data in hole and explaining data on the ground,engineering geological exploration formation density MWD is researched.The MWD works stabilized,and the performance is good with precise data.展开更多
Based on the rapid development of China's economy, the construction engineering industry is also in a state of sustainable development, and the total number of engineering projects has increased significantly. Fro...Based on the rapid development of China's economy, the construction engineering industry is also in a state of sustainable development, and the total number of engineering projects has increased significantly. From a certain point of view, the development of engineering projects has also promoted the rapid development of engineering project exploration industry. Hydrogeological problem investigation belongs to the key content of engineering geological exploration, and hydrogeological problems are the key factors causing engineering geological problems. Therefore, it is particularly important to clarify the impact of hydrogeological problems on engineering geological exploration and eliminate potential safety hazards as much as possible.展开更多
Jiama,with more than 11 Mt of copper metal,is the largest porphyry-skarn copper system in the Gangdese metallogenic belt,Xizang,China,creating ideal conditions for deciphering the origin of porphyry ores in a collisio...Jiama,with more than 11 Mt of copper metal,is the largest porphyry-skarn copper system in the Gangdese metallogenic belt,Xizang,China,creating ideal conditions for deciphering the origin of porphyry ores in a collision setting.Despite massive studies of the geology,chronology,petrogenesis,and ore-related fluids and their sources in Jiama,there is a lack of systematic summaries and reviews of this system.In contrast to traditional porphyry copper systems in a subduction setting,recent studies and exploration suggest that the Jiama deposit includes porphyry-type Mo-Cu,skarn-type Cu polymetallic,vein-type Au and manto orebodies.This paper reviews the latest studies on the geology,chronology,petrogenesis,fluid inclusions,and isotopic geochemistry(hydrogen,oxygen,sulfur,and lead)of the Jiama deposit.Accordingly,a multi-center complex mineralization model was constructed,indicating that multi-phase intrusions from the same magma reservoir can form multiple hydrothermal centers.These centers are mutually independent and form various orebodies or are superimposed on each other and form thick,high-grade orebodies.Finally,a new comprehensive exploration model was established for the Jiama porphyry copper system.Both models established in this study help to refine the theories on continental-collision metallogeny and porphyry copper systems.展开更多
The shale gas resources in China have great potential and the geological resources of shale gas is over 100×10^(12)m^(3),which includes about 20×10^(12)m^(3) of recoverable resources.Organic-rich shales can ...The shale gas resources in China have great potential and the geological resources of shale gas is over 100×10^(12)m^(3),which includes about 20×10^(12)m^(3) of recoverable resources.Organic-rich shales can be divided into three types according to their sedimentary environments,namely marine,marine-continental transitional,and continental shales,which are distributed in 13 stratigraphic systems from the Mesoproterozoic to the Cenozoic.The Sichuan Basin and its surrounding areas have the highest geological resources of shale gas,and the commercial development of shale gas has been achieved in the Upper Ordovician Wufeng Formation-Lower Silurian Longmaxi Formation in these areas,with a shale gas production of up to 20×10^(9)m^(3) in 2020.China has seen rapid shale gas exploration and development over the last five years,successively achieving breakthroughs and important findings in many areas and strata.The details are as follows.(1)Large-scale development of middle-shallow shale gas(burial depth:less than 3500 m)has been realized,with the productivity having rapidly increased;(2)breakthroughs have been constantly made in the development of deep shale gas(burial depth:3500-4500 m),and the ultradeep shale gas(burial depth:greater than 4500 m)is under testing;(3)breakthroughs have been made in the development of normal-pressure shale gas,and the assessment of the shale gas in complex tectonic areas is being accelerated;(4)shale gas has been frequently discovered in new areas and new strata,exhibiting a great prospect.Based on the exploration and development practice,three aspects of consensus have been gradually reached on the research progress in the geological theories of shale gas achieved in China.(1)in terms of deep-water fine-grained sediments,organic-rich shales are the base for the formation of shale gas;(2)in terms of high-quality reservoirs,the development of micro-nano organic matter-hosted pores serves as the core of shale gas accumulation;(3)in terms of preservation conditions,weak structural transformation,a moderate degree of thermal evolution,and a high pressure coefficient are the key to shale gas enrichment.As a type of important low-carbon fossil energy,shale gas will play an increasingly important role in achieving the strategic goals of peak carbon dioxide emissions and carbon neutrality.Based on the in-depth study of shale gas geological conditions and current exploration progress,three important directions for shale gas exploration in China in the next five years are put forward.展开更多
Since 2012,some advances have been made through the resource investigation,metallogenesis research,and comprehensive utilizing of lithium deposits in China.Firstly,the progress of lithium exploration has been made in ...Since 2012,some advances have been made through the resource investigation,metallogenesis research,and comprehensive utilizing of lithium deposits in China.Firstly,the progress of lithium exploration has been made in Sichuan,Xinjiang,Qinghai and Jiangxi provinces(autonomous region).Li deposits are not only found within the pegmatite rocks but also within the granitic rocks and sedimentary rocks.Secondly,the methods of geological survey,geochemical and geophysical exploration,remote sensing technology and even drilling technology have been improved,which can be delineating orebodies quickly.Thirdly,the mechanisms of Li mineralization were summarized by analyzing the relationship between the Li contents and kinds of geological phenomena.Based on practice,a new understanding of"multi-cycle,deep circulation,integration of internal and external"metallogenic mechanism or"MDIE"metallogenic mechanism for short has been put forwarded further in this paper,and the"five levels+basement"exploration model has been successfully expanded to guide the prospecting work both in the Jiajika and Keeryin pegmatite ore fields in western Sichuan Province.Besides,new progress has been made in the aspect of amblygonite deposits of granite-type and hydrothermal type in the Mufushan-Jiuling ore district,which points out a new direction for prospecting new types of lithium deposits in China.展开更多
The giant potash deposit on the Khorat Plateau is one of the most promising targets for exploitation of potassium salts.So far,many researches and geologic survey have been conducted on the giant potash deposits.Hence...The giant potash deposit on the Khorat Plateau is one of the most promising targets for exploitation of potassium salts.So far,many researches and geologic survey have been conducted on the giant potash deposits.Hence,it is necessary to make an overall review on the potash deposits.The potash deposit on the Khorat Plateau was formed during the Middle to Late Cretaceous,during which seawater was enriched in Ca2+and depleted in SO42-compared with those of modern seawater.In addition to seawater,continental water and hydrothermal fluids could have affected the evaporite basins.The seawater was probably derived from Tethys ocean,and the brine should have evaporated to some extent before entering into the basin systems based on the evidence of absence of carbonates and unproportionate sulphate compared with chloride salts.The paleo-climate during Middle to Late Cretaceous was characterized as high temperature and extremely arid environment,which is favourable for deposition of potassium-magnesium saline minerals.The major saline minerals are of anhydrite,halite,carnallite,sylvite and,tachyhydrite,with trace amounts of borates.The resources of the potash deposit on the Khorat Plateau could be approximately as much as 400×109 t of carnallite and 7×109 t of sylvite.The evaporite sequences have been deformed and altered by postdepositinal processes,including tectonic movements and chemical alteration.Salt domes were formed in the postdepositional processes.Based on the analyses of geophysical surveys and drilling projects,high-quality sylvinite ores are commonly found at the flanks of those salt domes due to incongruent dissolution of carnallite.The furure potential prospecting areas for the highquality sylvinite ores would be on the edges of the Khorat Plateau.展开更多
North Carnarvon Basin is a gas province with minor oily sweet spots in deepwater area with water depth more than 500 m,which is one of the hot spots of global petroleum exploration for its series of giant hydrocarbon ...North Carnarvon Basin is a gas province with minor oily sweet spots in deepwater area with water depth more than 500 m,which is one of the hot spots of global petroleum exploration for its series of giant hydrocarbon discoveries in recent years.However,the degree of oil and gas exploration in deepwater area is still low,and the conditions for oil and gas accumulation are not clear.Based on the current exploration situation and latest database of fields,applying multidisciplinary analysis of hydrocarbon geology,hydrocarbon accumulation elements and its exploration direction of North Carnarvon Basin in deepwater area are analyzed.The results show that there are three sets of main source rocks in deepwater area of North Carnarvon Basin,which are Triassic marine shale in Locker Formation and delta coal-bearing mudstone with thin carbonaceous mudstone in Mungaroo Formation,Lower–Middle Jurassic paralic carbargilite and coal measure strata in Athol Formation and Murat Formation,Cretaceous delta mudstone in Barrow Group and marine shale in Muderong Formation.Most source rock samples show gas-prone capability.The coarse sandstone of delta facies in Middle–Upper Triassic Mungaroo Formation is the most important reservoir in deepwater area,Lower Cretaceous Barrow Group deep-water gravity flow or underwater fan turbidite sandstone is the secondly main reservoir.Lower Cretaceous marine shale in Muderong Formation is most important regional caprock.Triassic mudstone in Mungaroo Formation is an important interlayer caprock in deepwater area.There are two main reservoir accumulation assemblages in deepwater area,one is Triassic structural-unconformity plane reservoir accumulation assemblage of Locker Formation to Mungaroo Formation,and the other is Lower–Middle Jurassic Athol Formation and Murat Formation–Lower Cretaceous stratigraphic lithology-structural reservoir accumulation assemblage of Barrow Group to Muderong Formation.There are three main control factors of hydrocarbon Accumulation:One is coupling of source and seal control hydrocarbon distribution area,the second is multi-stage large wave dominated deltas dominate accumulation zone,the third is direction of hydrocarbon migration and accumulation in hydrocarbon-rich generation depression was controlled by overpressure.The south of Exmouth platform in deepwater area is adjacent to hydrocarbon rich depression zone,reservoir assemblage is characterized by“near source rocks,excellent reservoir facies,high position and excellent caprocks”,which is the main battlefield of deepwater oil and gas exploration in North Carnarvon Basin at present.There are a lot of fault block traps in the northern structural belt of Exmouth platform,and the favorable sedimentary facies belt at the far end of delta plain in Mungaroo Formation is widely distributed,which is the next favorable exploration zone.The Lower Cretaceous,which is located at the concave edge uplift adjacent to the investigator depression and the Exmouth platform,also has a certain exploration prospect in northwest of deepwater area.展开更多
By the end of 2020,83 silver deposits(or ore occurrences),including four super-large-scale deposits,nine large-scale deposits,33 medium-scale deposits and 37 small-scale deposits or ore occurrences,have been proved.Th...By the end of 2020,83 silver deposits(or ore occurrences),including four super-large-scale deposits,nine large-scale deposits,33 medium-scale deposits and 37 small-scale deposits or ore occurrences,have been proved.The amount of silver metal exceeds 86000 t with average grade of 100 g/t,which makes Daxing’anling region one of the the most important silver ore belt in China.However,the metallogenic characteristics and metallogenesis need to be clarified.The silver deposits in the study area are classified into three main types,which are magmatic hydrothermal vein type,continental volcano-subvolcanic type and skarn type,respectively.The supergiant deposits include the Shuangjianzishan deposit(silver metal amount of 15214 t with average grade of 138 g/t),the Baiyinchagandongshan deposit(silver metal amount of 9446 t with average grade of 187 g/t),the Huaobaote deposit(silver metal amount of 6852 t with average grade of 170 g/t),and the Fuxingtun deposit(silver metal amount of 5240 t with average grade of 196 g/t).The silver deposits are mainly distributed in the central and south of the Daxing’anling area,and mainly formed in the Yanshanian period.The silver polymetallic deposits in the Daxinganling area are significantly controlled by regional faults and the junction zone of volcanic rock basins and their margins.The north-east trending deep faults are the most important ore-controlling structures in this area.The distribution of silver polymetallic deposits along the main faults is obvious,and the intersection area of multiple groups of faults often form important mine catchments.The Permian is the most important ore-bearing formation in this area,but some important silver polymetallic deposits occur in Mesozoic volcanic basins or pre-Mesozoic strata.The magmatic rocks related to mineralization are mainly intermediate acidic or acidic intrusions,intermediate acidic lavas,pyroclastic rocks,and small intrusions of ultra-shallow or shallow facies of the Yanshanian Period.The mineralization element combination is mainly determined by the elemental geochemical background of surrounding rocks or source layers.In addition,the type of deposit,the distance from the mineralization center,and the degree of differentiation of ore-forming rock mass are also important influence factors.The article analyzes the prospecting prospects of each silver deposit type in the study area,discusses the relationship between mineralization center and deep prospecting,and proposes that porphyry silver deposits should be paid attention to.In the prospecting and exploration of silver deposits,comprehensive evaluation and multi-target prospecting need to be strengthened because silver can coexist or be associated with a variety of metals.展开更多
The Hot Dry Rock(HDR)is considered as a clean and renewable energy,poised to significantly contribute to the global energy decarbonization agenda.Many HDR projects worldwide have accumulated valuable experience in eff...The Hot Dry Rock(HDR)is considered as a clean and renewable energy,poised to significantly contribute to the global energy decarbonization agenda.Many HDR projects worldwide have accumulated valuable experience in efficient drilling and completion,reservoir construction,and fracture simulation.In 2019,China Geological Survey(CGS)initiated a demonstration project of HDR exploration and production in the Gonghe Basin,aiming to overcome the setbacks faced by HDR projects.Over the ensuing four years,the Gonghe HDR project achieved the first power generation in 2021,followed by the second power generation test in 2022.After establishing the primary well group in the initial phase,two directional wells and one branch well were drilled.Noteworthy progress was made in successfully constructing the targeted reservoir,realizing inter-well connectivity,power generation and grid connection,implementing of the real-time micro-seismic monitoring.A closed-loop technical validation of the HDR exploration and production was completed.However,many technical challenges remain in the process of HDR industrialization,such as reservoir fracture network characterization,efficient drilling and completion,multiple fracturing treatment,continuous injection and production,as well as mitigation of induced seismicity and numerical simulation technology.展开更多
Recently,continuous breakthroughs have been made about deep gold prospecting in the Jiaodong gold province area of China.Approximately 5000 t of cumulative gold resources have been explored in Jiaodong,which has thus ...Recently,continuous breakthroughs have been made about deep gold prospecting in the Jiaodong gold province area of China.Approximately 5000 t of cumulative gold resources have been explored in Jiaodong,which has thus become an internationally noteworthy gold ore cluster.The gold exploration depth has been increased to about 2000 m from the previous<1000 m.To further explore the mineralization potential of the Jiaodong area at a depth of about 3000 m,the Shandong Institute of Geological Sciences has drilled an exploratory drillhole named“Deep drillhole ZK01”to a depth of 3266 m.Hence,as reported herein,the mineralization characteristics of the Jiaojia metallogenic belt have been successfully documented.ZK01 is,to date,the deepest borehole with an gold intersect in China,and constitutes a significant advance in deep gold prospecting in China.The findings of this study further indicate that the depth interval of 2000 m to 4000 m below the ground surface in the Wuyi Village area incorporates 912 t of inferred gold resources,while the depth interval of 2000 m to 4000 m below the surface across the Jiaodong area possesses about 4000 t of inferred gold resources.The Jiaojia Fault Belt tends to gently dip downward,having dip angles of about 25°and about 20°at vertical depths of 2000 m and 2850 m,respectively.The deep part of the Jiaojia metallogenic belt differs from the shallow and moderately deep parts about fracturing,alteration,mineralization,and tectonic type.The deep zones can generally be categorized from inside outward as cataclastic granite,granitic cataclasite,weakly beresitized granitic cataclasite,beresitized cataclasite,and gouge.These zones exhibit a gradual transitional relation or occur alternately and repeatedly.The mineralization degree of the pyritized cataclastic granite-type ore in the deep part of the Jiaojia metallogenic belt is closely related to the degree of pyrite vein development;that is,the higher the pyrite content,the wider the veins and the higher the gold grade.Compared to the shallow gold ores,the deep-seated gold ores have higher fineness and contain joseite,tetradymite,and native bismuth,suggesting that the deep gold mineralization temperature is higher and that mantle-sourced material may have contributed to this mineralization.ZK01 has also revealed that the deep-seated ore bodies in the Jiaojia metallogenic belt are principally situated above the main fracture plane(gouge)and hosted within the Linglong Granite,contradicting previous findings indicating that the moderately shallow gold ore bodies are usually hosted in the contact zone between the Linglong Granite and Jiaodong Group or meta-gabbro.These new discoveries are particularly significant because they can help correct mineralization prospecting models,determine favorable positions for deep prospecting,and improve metallogenic prediction and resource potential evaluation.展开更多
Shenhu area in South China Sea includes extensive collapse and diapir structures,forming high-angle faults and vertical fracture system,which functions as a fluid migration channel for gas hydrate formation.In order t...Shenhu area in South China Sea includes extensive collapse and diapir structures,forming high-angle faults and vertical fracture system,which functions as a fluid migration channel for gas hydrate formation.In order to improve the imaging precision of natural gas hydrate in this area,especially for fault and fracture structures,the present work propose a velocity stitching technique that accelerates effectively the convergence of the shallow seafloor,indicating seafloor horizon interpretation and the initial interval velocity for model building.In the depth domain,pre-stack depth migration and residual curvature are built into the model based on high-precision grid-tomography velocity inversion,after several rounds of tomographic iterations,as the residual velocity field converges gradually.Test results of the Shenhu area show that the imaging precision of the fault zone is obviously improved,the fracture structures appear more clearly,the wave group characteristics significantly change for the better and the signal-to-noise ratio and resolution are improved.These improvements provide the necessary basis for the new reservoir model and field drilling risk tips,help optimize the favorable drilling target,and are crucial for the natural gas resource potential evaluation.展开更多
Conductor and suction anchor are the key equipment providing bearing capacity in the field of deep-water drilling or offshore engineering,which have the advantages of high operation efficiency and short construction p...Conductor and suction anchor are the key equipment providing bearing capacity in the field of deep-water drilling or offshore engineering,which have the advantages of high operation efficiency and short construction period.In order to drill a horizontal well in the shallow hydrate reservoir in the deep water,the suction anchor wellhead assembly is employed to undertake the main vertical bearing capacity in the second round of hydrate trial production project,so as to reduce the conductor running depth and heighten the kick-off point position.However,the deformation law of the deep-water suction anchor wellhead assembly under the moving load of the riser is not clear,and it is necessary to understand the lateral bearing characteristics to guide the design of its structural scheme.Based on 3D solid finite element method,the solid finite element model of the suction anchor wellhead assembly is established.In the model,the seabed soil is divided into seven layers,the contact between the wellhead assembly and the soil is simulated,and the vertical load and bending moment are applied to the wellhead node to simulate the riser movement when working in the deep water.The lateral bearing stability of conventional wellhead assembly and suction anchor wellhead assembly under the influence of wellhead load is discussed.The analysis results show that the bending moment is the main factor affecting the lateral deformation of the wellhead string;the anti-bending performance from increasing the outer conductor diameter is better than that from increasing the conductor wall thickness;for the subsea wellhead,the suction anchor obviously improves the lateral bearing capacity and reduces the lateral deformation.The conduct of the suction anchor wellhead assembly still needs to be lowered to a certain depth that below the maximum disturbed depth to ensure the lateral bearing stability,Thus,a method for the minimum conductor running depth for the suction anchor wellhead assembly is developed.The field implementations show that compared with the first round of hydrate trial production project,the conductor running depth is increased by 9.42 m,and there is no risk of wellhead overturning during the trial production.The method for determining the minimum conductor running depth in this paper is feasible and will still play an important role in the subsequent hydrate exploration and development.展开更多
Under the impetus of social economy, the scale of urbanization is expanding continuously. At the same time, engineering geological survey has also played an important role in the process of urbanization construction a...Under the impetus of social economy, the scale of urbanization is expanding continuously. At the same time, engineering geological survey has also played an important role in the process of urbanization construction and planning. Before the formal opening of the construction project, scientific and reasonable investigation must be carried out on the hydrogeological conditions of the construction area in order to ensure the smooth development of the later construction. The accuracy of engineering geological survey results will directly affect the subsequent engineering, and the main factor that affects the engineering geological survey is the hydrogeological conditions in the monitoring area. Therefore, hydrogeological problems have become the key factors in engineering geological investigation. This paper mainly analyzes the investigation content of hydrogeological conditions in the process of engineering geological investigation, and discusses the influence of engineering geological investigation on hydrogeological problems, hoping to provide reference for the relative staff to carry out engineering geological investigation.Keywords: hydrogeology;engineering geological exploration;impact展开更多
This research optimized the structure of lithium extraction solar ponds to enhance the crystallization rate and yield of Li_(2)CO_(3).Using the response surface methodology in Design-Expert 10.0.3,the authors conducte...This research optimized the structure of lithium extraction solar ponds to enhance the crystallization rate and yield of Li_(2)CO_(3).Using the response surface methodology in Design-Expert 10.0.3,the authors conducted experiments to investigate the influence of four factors related to solar pond structure on the crystallization of Li_(2)CO_(3) and their pairwise interactions.Computational Fluid Dynamics(CFD)simulations of the flow field within the solar pond were performed using COMSOL Multiphysics software to compare temperature distributions before and after optimization.The results indicate that the optimal structure for lithium extraction from the Zabuye Salt Lake solar ponds includes UCZ(Upper Convective Zone)thickness of 53.63 cm,an LCZ(Lower Convective Zone)direct heating temperature of 57.39℃,a CO32−concentration of 32.21 g/L,and an added soda ash concentration of 6.52 g/L.Following this optimized pathway,the Li_(2)CO_(3) precipitation increased by 7.34% compared to the initial solar pond process,with a 33.33% improvement in lithium carbonate crystallization rate.This study demonstrates the feasibility of optimizing lithium extraction solar pond structures,offering a new approach for constructing such ponds in salt lakes.It provides valuable guidance for the efficient extraction of lithium resources from carbonate-type salt lake brines.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
Natural gas hydrate is a clean energy source with substantial resource potential.In contrast to conventional oil and gas,natural gas hydrate exists as a multi-phase system consisting of solids,liquids,and gases,which ...Natural gas hydrate is a clean energy source with substantial resource potential.In contrast to conventional oil and gas,natural gas hydrate exists as a multi-phase system consisting of solids,liquids,and gases,which presents unique challenges and complicates the mechanisms of seepage and exploitation.Both domestic and international natural gas hydrate production tests typically employ a single-well production model.Although this approach has seen some success,it continues to be hindered by low production rates and short production cycles.Therefore,there is an urgent need to explore a new well network to significantly increase the production of a single well.This paper provides a comprehensive review of the latest advancements in natural gas hydrate research,including both laboratory studies and field tests.It further examines the gas production processes and development outcomes for single wells,dual wells,multi-branch wells,and multi-well systems under conditions of depressurization,thermal injection,and CO_(2) replacement.On this basis,well types and well networks suitable for commercial exploitation of natural gas hydrate were explored,and the technical direction of natural gas hydrate development was proposed.The study shows that fully exploiting the flexibility of complex structural wells and designing a well network compatible with the reservoir is the key to improving production from a single well.Moreover,multi-well joint exploitation is identified as an effective strategy for achieving large-scale,efficient development of natural gas hydrate.展开更多
With the development of the new energy industry and the depletion of nickel sulfide ore resources,laterite nickel ore has become the main source of primary nickel,and nickel for power batteries has become a new growth...With the development of the new energy industry and the depletion of nickel sulfide ore resources,laterite nickel ore has become the main source of primary nickel,and nickel for power batteries has become a new growth point in consumption.This paper systematically summarizes the processes,parameters,products,recovery rates,environmental indicators,costs,advantages,disadvantages and the latest research progress of mainstream nickel extraction processes from laterite nickel ore.It also provides a comparative analysis of the environmental impact and economic efficiency of different nickel extraction processes.It is found that the current nickel extraction processes from laterite nickel ore globally for commercial production mainly include the RKEF process for producing ferronickel and the HPAL process for producing intermediate products.The former accounts for about 80%of laterite nickel ore production.Compared to each other,the investment cost per ton of nickel metal production capacity for the RKEF is about 43000$,with an operational cost of about 16000$per ton of nickel metal and a total nickel recovery rate of 77%–90%.Its products are mainly used in stainless steels.For the HPAL process,the investment cost per ton of nickel metal production capacity is about 56000$,with an operational cost of about 15000$per ton of nickel metal and a total nickel recovery rate of 83%–90%.Its products are mainly used in power batteries.The significant differences between the two lies in energy consumption and carbon emissions,with the RKEF being 2.18 and 2.37 times that of the HPAL,respectively.Although the use of clean energy can greatly reduce the operational cost and environmental impact of RKEF,if RKEF is converted to producing high Ni matte,its economic and environmental performance still cannot match that of the HPAL and oxygen-enriched side-blown processes.Therefore,it can be inferred that with the increasing demand for nickel in power batteries,HPAL and oxygen-enriched side blowing processes will play a greater role in laterite nickel extraction.展开更多
The strike-slip fault system in the central Tarim Craton controls a complex petroleum system with estimated reserves exceeding 1×10^(9)t,the fault-related fractures are important for hydrocarbon accumulation.In t...The strike-slip fault system in the central Tarim Craton controls a complex petroleum system with estimated reserves exceeding 1×10^(9)t,the fault-related fractures are important for hydrocarbon accumulation.In this paper,the basic parameters such as density and width of fractures are counted and classified,and the effects of fractures on reservoirs are analyzed.The results show that:(1)Structural fractures and stylolite were widely developed in Halahatang area and experienced at least three stages of activity based on the infilling materials and crosscutting relationship.(2)Fracture density,width,aperture,and dip angle vary in different wells,but the relationship between the above parameters and the distance to the fault core indicates the fracture differences in the fault damage zone and further provides a method to divide the inner units in the fault damage zone.In addition,oil and gas wells with high production mainly concentrate in the inner unit.(3)The infilling materials and degree of fractures vary.Fractures formed in the early stage are more filled and less open,while the fractures formed in the late stage are relatively less filled and more open.(4)Fractures improve porosity to a certain extent but greatly increase permeability,especially in the inner zone of fault damage zone with large quantity,multiple inclinations,less filling and large width.These features contribute to the formation of a higher-quality reservoir,further improving oil and gas production.This paper provides a quantitative characterization method for the study of strike-slip fault-related fracture-caved reservoirs,and points out that fault damage zone,especially the inner zone of the fault damage zone,is the potential goal for oil and gas exploration.展开更多
文摘Based on the ArcGIS geographic information system and the ORACLE database management system,this paper reports our studies on the technology of Marine Engineering Geological Exploration Information System(MEGEIS). By analyzing system structure,designing function modules and discussing data management,this paper systematically proposes a framework of technol-ogy to integrate,manage,and analyze the seabed information comprehensively. Then,the technology is applied to the design and development of the Bohai Sea Oilfield Paradigm Area Information System. The system can not only meet the practical demands of marine resources exploration and exploitation in the Bohai Sea oilfield,but also serve as a preparatory work in theory and technology for the realization of the 'Digital Seabed'.
文摘In recent years, based on the rapid development of our country's social economy, the utilization of geological and mineral resources is also increasing, and its mining will directly affect the sustainable development of our country's economic construction, so in order to meet the market demand, geological exploration technology needs to keep pace with the times, and constantly carry out reform and optimization. In the actual mining work, the application of geological exploration technology can greatly improve its work efficiency. However, its safety cannot be ignored, it will directly affect the development of geological exploration. All along, our country has abundant mineral resources, which can effectively promote the improvement of our country's social and economic level. Mineral resources are non-renewable energy, so the best exploration technology should be used in the mining and use of mineral resources, so as to achieve the purpose of orderly development of the whole work.
文摘A high efficiency method is very important in geological survey for a new city in China.Geophysical parameters are Measured While Drilling(MWD),and these parameters are processed and explained on the ground,so the method can replace conventional engineering geological exploration for drilling rock sample.According petroleum engineering MWD,using the different characters of different rock absorbs γ radial,with the method of storing data in hole and explaining data on the ground,engineering geological exploration formation density MWD is researched.The MWD works stabilized,and the performance is good with precise data.
文摘Based on the rapid development of China's economy, the construction engineering industry is also in a state of sustainable development, and the total number of engineering projects has increased significantly. From a certain point of view, the development of engineering projects has also promoted the rapid development of engineering project exploration industry. Hydrogeological problem investigation belongs to the key content of engineering geological exploration, and hydrogeological problems are the key factors causing engineering geological problems. Therefore, it is particularly important to clarify the impact of hydrogeological problems on engineering geological exploration and eliminate potential safety hazards as much as possible.
基金supported by the National Key Research and Development Program of China(2022YFC2905001)the National Natural Science Foundation of China(42272093,42230813)+1 种基金China Scholarship Council projectthe Geological Survey project(DD20230054)
文摘Jiama,with more than 11 Mt of copper metal,is the largest porphyry-skarn copper system in the Gangdese metallogenic belt,Xizang,China,creating ideal conditions for deciphering the origin of porphyry ores in a collision setting.Despite massive studies of the geology,chronology,petrogenesis,and ore-related fluids and their sources in Jiama,there is a lack of systematic summaries and reviews of this system.In contrast to traditional porphyry copper systems in a subduction setting,recent studies and exploration suggest that the Jiama deposit includes porphyry-type Mo-Cu,skarn-type Cu polymetallic,vein-type Au and manto orebodies.This paper reviews the latest studies on the geology,chronology,petrogenesis,fluid inclusions,and isotopic geochemistry(hydrogen,oxygen,sulfur,and lead)of the Jiama deposit.Accordingly,a multi-center complex mineralization model was constructed,indicating that multi-phase intrusions from the same magma reservoir can form multiple hydrothermal centers.These centers are mutually independent and form various orebodies or are superimposed on each other and form thick,high-grade orebodies.Finally,a new comprehensive exploration model was established for the Jiama porphyry copper system.Both models established in this study help to refine the theories on continental-collision metallogeny and porphyry copper systems.
基金supported by a project of shale gas in Southern China(DD20190561)initiated by the China Geological Surveythe project for High-level Innovative Talents in Science and Technology,Ministry of Natural Resources(12110600000018003918)。
文摘The shale gas resources in China have great potential and the geological resources of shale gas is over 100×10^(12)m^(3),which includes about 20×10^(12)m^(3) of recoverable resources.Organic-rich shales can be divided into three types according to their sedimentary environments,namely marine,marine-continental transitional,and continental shales,which are distributed in 13 stratigraphic systems from the Mesoproterozoic to the Cenozoic.The Sichuan Basin and its surrounding areas have the highest geological resources of shale gas,and the commercial development of shale gas has been achieved in the Upper Ordovician Wufeng Formation-Lower Silurian Longmaxi Formation in these areas,with a shale gas production of up to 20×10^(9)m^(3) in 2020.China has seen rapid shale gas exploration and development over the last five years,successively achieving breakthroughs and important findings in many areas and strata.The details are as follows.(1)Large-scale development of middle-shallow shale gas(burial depth:less than 3500 m)has been realized,with the productivity having rapidly increased;(2)breakthroughs have been constantly made in the development of deep shale gas(burial depth:3500-4500 m),and the ultradeep shale gas(burial depth:greater than 4500 m)is under testing;(3)breakthroughs have been made in the development of normal-pressure shale gas,and the assessment of the shale gas in complex tectonic areas is being accelerated;(4)shale gas has been frequently discovered in new areas and new strata,exhibiting a great prospect.Based on the exploration and development practice,three aspects of consensus have been gradually reached on the research progress in the geological theories of shale gas achieved in China.(1)in terms of deep-water fine-grained sediments,organic-rich shales are the base for the formation of shale gas;(2)in terms of high-quality reservoirs,the development of micro-nano organic matter-hosted pores serves as the core of shale gas accumulation;(3)in terms of preservation conditions,weak structural transformation,a moderate degree of thermal evolution,and a high pressure coefficient are the key to shale gas enrichment.As a type of important low-carbon fossil energy,shale gas will play an increasingly important role in achieving the strategic goals of peak carbon dioxide emissions and carbon neutrality.Based on the in-depth study of shale gas geological conditions and current exploration progress,three important directions for shale gas exploration in China in the next five years are put forward.
基金This research has been supported by the China National Key Research and Development Program during the“13th Five-year Plan Period”(2017YFC0602700)the Geological Survey Projects of China Geological Survey(DD20160056,DD20160346)the Major Project of National Social Science Fund“Research on the supply risk management mechanism for China’s strategic three-rare mineral resources”(19ZDA111).
文摘Since 2012,some advances have been made through the resource investigation,metallogenesis research,and comprehensive utilizing of lithium deposits in China.Firstly,the progress of lithium exploration has been made in Sichuan,Xinjiang,Qinghai and Jiangxi provinces(autonomous region).Li deposits are not only found within the pegmatite rocks but also within the granitic rocks and sedimentary rocks.Secondly,the methods of geological survey,geochemical and geophysical exploration,remote sensing technology and even drilling technology have been improved,which can be delineating orebodies quickly.Thirdly,the mechanisms of Li mineralization were summarized by analyzing the relationship between the Li contents and kinds of geological phenomena.Based on practice,a new understanding of"multi-cycle,deep circulation,integration of internal and external"metallogenic mechanism or"MDIE"metallogenic mechanism for short has been put forwarded further in this paper,and the"five levels+basement"exploration model has been successfully expanded to guide the prospecting work both in the Jiajika and Keeryin pegmatite ore fields in western Sichuan Province.Besides,new progress has been made in the aspect of amblygonite deposits of granite-type and hydrothermal type in the Mufushan-Jiuling ore district,which points out a new direction for prospecting new types of lithium deposits in China.
基金This study is finished through the cooperation project between China Geological Survey and Department of Mineral Resources(Thailand)supported by the National Key Project for Basic Research of China(2011CB403007)+2 种基金the National Natural Science Foundation of China(41572067,91855104,41802111)the Geological Survey Project(DD20190437)"Mineral potential exploration and assessment for potash"by the Government of Thailand.
文摘The giant potash deposit on the Khorat Plateau is one of the most promising targets for exploitation of potassium salts.So far,many researches and geologic survey have been conducted on the giant potash deposits.Hence,it is necessary to make an overall review on the potash deposits.The potash deposit on the Khorat Plateau was formed during the Middle to Late Cretaceous,during which seawater was enriched in Ca2+and depleted in SO42-compared with those of modern seawater.In addition to seawater,continental water and hydrothermal fluids could have affected the evaporite basins.The seawater was probably derived from Tethys ocean,and the brine should have evaporated to some extent before entering into the basin systems based on the evidence of absence of carbonates and unproportionate sulphate compared with chloride salts.The paleo-climate during Middle to Late Cretaceous was characterized as high temperature and extremely arid environment,which is favourable for deposition of potassium-magnesium saline minerals.The major saline minerals are of anhydrite,halite,carnallite,sylvite and,tachyhydrite,with trace amounts of borates.The resources of the potash deposit on the Khorat Plateau could be approximately as much as 400×109 t of carnallite and 7×109 t of sylvite.The evaporite sequences have been deformed and altered by postdepositinal processes,including tectonic movements and chemical alteration.Salt domes were formed in the postdepositional processes.Based on the analyses of geophysical surveys and drilling projects,high-quality sylvinite ores are commonly found at the flanks of those salt domes due to incongruent dissolution of carnallite.The furure potential prospecting areas for the highquality sylvinite ores would be on the edges of the Khorat Plateau.
基金This study was funded by Jiangxi Provincial Natural Science Foundation(20202BABL211019)the National Science and Technology Major Project(2016ZX05026007)+2 种基金the National Major Fundamental Research and Development Project(2009CB219400)Open Fund Project of Key Laboratory of Sedimentary Mineralization and Sedimentary Mineral Resources in Shandong Province(DMSM 2019008)National Natural Science Foundation of China(41502081).
文摘North Carnarvon Basin is a gas province with minor oily sweet spots in deepwater area with water depth more than 500 m,which is one of the hot spots of global petroleum exploration for its series of giant hydrocarbon discoveries in recent years.However,the degree of oil and gas exploration in deepwater area is still low,and the conditions for oil and gas accumulation are not clear.Based on the current exploration situation and latest database of fields,applying multidisciplinary analysis of hydrocarbon geology,hydrocarbon accumulation elements and its exploration direction of North Carnarvon Basin in deepwater area are analyzed.The results show that there are three sets of main source rocks in deepwater area of North Carnarvon Basin,which are Triassic marine shale in Locker Formation and delta coal-bearing mudstone with thin carbonaceous mudstone in Mungaroo Formation,Lower–Middle Jurassic paralic carbargilite and coal measure strata in Athol Formation and Murat Formation,Cretaceous delta mudstone in Barrow Group and marine shale in Muderong Formation.Most source rock samples show gas-prone capability.The coarse sandstone of delta facies in Middle–Upper Triassic Mungaroo Formation is the most important reservoir in deepwater area,Lower Cretaceous Barrow Group deep-water gravity flow or underwater fan turbidite sandstone is the secondly main reservoir.Lower Cretaceous marine shale in Muderong Formation is most important regional caprock.Triassic mudstone in Mungaroo Formation is an important interlayer caprock in deepwater area.There are two main reservoir accumulation assemblages in deepwater area,one is Triassic structural-unconformity plane reservoir accumulation assemblage of Locker Formation to Mungaroo Formation,and the other is Lower–Middle Jurassic Athol Formation and Murat Formation–Lower Cretaceous stratigraphic lithology-structural reservoir accumulation assemblage of Barrow Group to Muderong Formation.There are three main control factors of hydrocarbon Accumulation:One is coupling of source and seal control hydrocarbon distribution area,the second is multi-stage large wave dominated deltas dominate accumulation zone,the third is direction of hydrocarbon migration and accumulation in hydrocarbon-rich generation depression was controlled by overpressure.The south of Exmouth platform in deepwater area is adjacent to hydrocarbon rich depression zone,reservoir assemblage is characterized by“near source rocks,excellent reservoir facies,high position and excellent caprocks”,which is the main battlefield of deepwater oil and gas exploration in North Carnarvon Basin at present.There are a lot of fault block traps in the northern structural belt of Exmouth platform,and the favorable sedimentary facies belt at the far end of delta plain in Mungaroo Formation is widely distributed,which is the next favorable exploration zone.The Lower Cretaceous,which is located at the concave edge uplift adjacent to the investigator depression and the Exmouth platform,also has a certain exploration prospect in northwest of deepwater area.
基金financially supported by the projects of China Geological Survey(DD20221695,DD20160346 and DD20190379)the Fundamental Research Funds of the Central Public Welfare Scientific Research Institutes(JYYWF20183701 and JYYWF20183704)the Inner Mongolia Geological Exploration Fund Project(2020-YS03).
文摘By the end of 2020,83 silver deposits(or ore occurrences),including four super-large-scale deposits,nine large-scale deposits,33 medium-scale deposits and 37 small-scale deposits or ore occurrences,have been proved.The amount of silver metal exceeds 86000 t with average grade of 100 g/t,which makes Daxing’anling region one of the the most important silver ore belt in China.However,the metallogenic characteristics and metallogenesis need to be clarified.The silver deposits in the study area are classified into three main types,which are magmatic hydrothermal vein type,continental volcano-subvolcanic type and skarn type,respectively.The supergiant deposits include the Shuangjianzishan deposit(silver metal amount of 15214 t with average grade of 138 g/t),the Baiyinchagandongshan deposit(silver metal amount of 9446 t with average grade of 187 g/t),the Huaobaote deposit(silver metal amount of 6852 t with average grade of 170 g/t),and the Fuxingtun deposit(silver metal amount of 5240 t with average grade of 196 g/t).The silver deposits are mainly distributed in the central and south of the Daxing’anling area,and mainly formed in the Yanshanian period.The silver polymetallic deposits in the Daxinganling area are significantly controlled by regional faults and the junction zone of volcanic rock basins and their margins.The north-east trending deep faults are the most important ore-controlling structures in this area.The distribution of silver polymetallic deposits along the main faults is obvious,and the intersection area of multiple groups of faults often form important mine catchments.The Permian is the most important ore-bearing formation in this area,but some important silver polymetallic deposits occur in Mesozoic volcanic basins or pre-Mesozoic strata.The magmatic rocks related to mineralization are mainly intermediate acidic or acidic intrusions,intermediate acidic lavas,pyroclastic rocks,and small intrusions of ultra-shallow or shallow facies of the Yanshanian Period.The mineralization element combination is mainly determined by the elemental geochemical background of surrounding rocks or source layers.In addition,the type of deposit,the distance from the mineralization center,and the degree of differentiation of ore-forming rock mass are also important influence factors.The article analyzes the prospecting prospects of each silver deposit type in the study area,discusses the relationship between mineralization center and deep prospecting,and proposes that porphyry silver deposits should be paid attention to.In the prospecting and exploration of silver deposits,comprehensive evaluation and multi-target prospecting need to be strengthened because silver can coexist or be associated with a variety of metals.
基金Funded by the“Investigation and Evaluation of the Hot Dry Rock Resources in the Guide-Dalianhai Area of the Gonghe Basin,Qinghai”(DD20211336,DD20211337,DD20211338)“Hot Dry Rock Resources Exploration and Production Demonstration Project”(DD20230018)of the China Geological Survey。
文摘The Hot Dry Rock(HDR)is considered as a clean and renewable energy,poised to significantly contribute to the global energy decarbonization agenda.Many HDR projects worldwide have accumulated valuable experience in efficient drilling and completion,reservoir construction,and fracture simulation.In 2019,China Geological Survey(CGS)initiated a demonstration project of HDR exploration and production in the Gonghe Basin,aiming to overcome the setbacks faced by HDR projects.Over the ensuing four years,the Gonghe HDR project achieved the first power generation in 2021,followed by the second power generation test in 2022.After establishing the primary well group in the initial phase,two directional wells and one branch well were drilled.Noteworthy progress was made in successfully constructing the targeted reservoir,realizing inter-well connectivity,power generation and grid connection,implementing of the real-time micro-seismic monitoring.A closed-loop technical validation of the HDR exploration and production was completed.However,many technical challenges remain in the process of HDR industrialization,such as reservoir fracture network characterization,efficient drilling and completion,multiple fracturing treatment,continuous injection and production,as well as mitigation of induced seismicity and numerical simulation technology.
基金by the National Natural Science Foundation of China(41772076,41672084,41372086,41503038)the National Key Research and Development Program of China(2016YFC0600105-04,2016YFC0600606)+1 种基金the Key Research and Development Program of Shandong Province(2017CXGC1601,2017CXGC1602,2017CXGC1603),the Special Fund for“Taishan Scholars”Project of Shandong Province.
文摘Recently,continuous breakthroughs have been made about deep gold prospecting in the Jiaodong gold province area of China.Approximately 5000 t of cumulative gold resources have been explored in Jiaodong,which has thus become an internationally noteworthy gold ore cluster.The gold exploration depth has been increased to about 2000 m from the previous<1000 m.To further explore the mineralization potential of the Jiaodong area at a depth of about 3000 m,the Shandong Institute of Geological Sciences has drilled an exploratory drillhole named“Deep drillhole ZK01”to a depth of 3266 m.Hence,as reported herein,the mineralization characteristics of the Jiaojia metallogenic belt have been successfully documented.ZK01 is,to date,the deepest borehole with an gold intersect in China,and constitutes a significant advance in deep gold prospecting in China.The findings of this study further indicate that the depth interval of 2000 m to 4000 m below the ground surface in the Wuyi Village area incorporates 912 t of inferred gold resources,while the depth interval of 2000 m to 4000 m below the surface across the Jiaodong area possesses about 4000 t of inferred gold resources.The Jiaojia Fault Belt tends to gently dip downward,having dip angles of about 25°and about 20°at vertical depths of 2000 m and 2850 m,respectively.The deep part of the Jiaojia metallogenic belt differs from the shallow and moderately deep parts about fracturing,alteration,mineralization,and tectonic type.The deep zones can generally be categorized from inside outward as cataclastic granite,granitic cataclasite,weakly beresitized granitic cataclasite,beresitized cataclasite,and gouge.These zones exhibit a gradual transitional relation or occur alternately and repeatedly.The mineralization degree of the pyritized cataclastic granite-type ore in the deep part of the Jiaojia metallogenic belt is closely related to the degree of pyrite vein development;that is,the higher the pyrite content,the wider the veins and the higher the gold grade.Compared to the shallow gold ores,the deep-seated gold ores have higher fineness and contain joseite,tetradymite,and native bismuth,suggesting that the deep gold mineralization temperature is higher and that mantle-sourced material may have contributed to this mineralization.ZK01 has also revealed that the deep-seated ore bodies in the Jiaojia metallogenic belt are principally situated above the main fracture plane(gouge)and hosted within the Linglong Granite,contradicting previous findings indicating that the moderately shallow gold ore bodies are usually hosted in the contact zone between the Linglong Granite and Jiaodong Group or meta-gabbro.These new discoveries are particularly significant because they can help correct mineralization prospecting models,determine favorable positions for deep prospecting,and improve metallogenic prediction and resource potential evaluation.
基金This study was financially supported by the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(GML2019ZD0207)Dedicated Fund for Promoting High-Quality Economic Development in Guangdong Province(Marine Economic Development Project)(GDNRC[2020]045)the State Key Laboratory of Marine Geology of Tongji University(MGK202007).
文摘Shenhu area in South China Sea includes extensive collapse and diapir structures,forming high-angle faults and vertical fracture system,which functions as a fluid migration channel for gas hydrate formation.In order to improve the imaging precision of natural gas hydrate in this area,especially for fault and fracture structures,the present work propose a velocity stitching technique that accelerates effectively the convergence of the shallow seafloor,indicating seafloor horizon interpretation and the initial interval velocity for model building.In the depth domain,pre-stack depth migration and residual curvature are built into the model based on high-precision grid-tomography velocity inversion,after several rounds of tomographic iterations,as the residual velocity field converges gradually.Test results of the Shenhu area show that the imaging precision of the fault zone is obviously improved,the fracture structures appear more clearly,the wave group characteristics significantly change for the better and the signal-to-noise ratio and resolution are improved.These improvements provide the necessary basis for the new reservoir model and field drilling risk tips,help optimize the favorable drilling target,and are crucial for the natural gas resource potential evaluation.
基金This research was jointly supported by the National Key R&D Program of China(2021YFC2800801)the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(GML2019ZD0501)+3 种基金the Guangzhou Basic and Applied Basic Foundation(202102020611)the project of Guangzhou Marine Geological Survey of the China Geology Survey(DD20221700)the Key-Area Research and Development Program of Guangdong Province(2020B1111030003)the High-tech Ship Research Project of the Ministry of Industry and Information Technology(CJ05N20).
文摘Conductor and suction anchor are the key equipment providing bearing capacity in the field of deep-water drilling or offshore engineering,which have the advantages of high operation efficiency and short construction period.In order to drill a horizontal well in the shallow hydrate reservoir in the deep water,the suction anchor wellhead assembly is employed to undertake the main vertical bearing capacity in the second round of hydrate trial production project,so as to reduce the conductor running depth and heighten the kick-off point position.However,the deformation law of the deep-water suction anchor wellhead assembly under the moving load of the riser is not clear,and it is necessary to understand the lateral bearing characteristics to guide the design of its structural scheme.Based on 3D solid finite element method,the solid finite element model of the suction anchor wellhead assembly is established.In the model,the seabed soil is divided into seven layers,the contact between the wellhead assembly and the soil is simulated,and the vertical load and bending moment are applied to the wellhead node to simulate the riser movement when working in the deep water.The lateral bearing stability of conventional wellhead assembly and suction anchor wellhead assembly under the influence of wellhead load is discussed.The analysis results show that the bending moment is the main factor affecting the lateral deformation of the wellhead string;the anti-bending performance from increasing the outer conductor diameter is better than that from increasing the conductor wall thickness;for the subsea wellhead,the suction anchor obviously improves the lateral bearing capacity and reduces the lateral deformation.The conduct of the suction anchor wellhead assembly still needs to be lowered to a certain depth that below the maximum disturbed depth to ensure the lateral bearing stability,Thus,a method for the minimum conductor running depth for the suction anchor wellhead assembly is developed.The field implementations show that compared with the first round of hydrate trial production project,the conductor running depth is increased by 9.42 m,and there is no risk of wellhead overturning during the trial production.The method for determining the minimum conductor running depth in this paper is feasible and will still play an important role in the subsequent hydrate exploration and development.
文摘Under the impetus of social economy, the scale of urbanization is expanding continuously. At the same time, engineering geological survey has also played an important role in the process of urbanization construction and planning. Before the formal opening of the construction project, scientific and reasonable investigation must be carried out on the hydrogeological conditions of the construction area in order to ensure the smooth development of the later construction. The accuracy of engineering geological survey results will directly affect the subsequent engineering, and the main factor that affects the engineering geological survey is the hydrogeological conditions in the monitoring area. Therefore, hydrogeological problems have become the key factors in engineering geological investigation. This paper mainly analyzes the investigation content of hydrogeological conditions in the process of engineering geological investigation, and discusses the influence of engineering geological investigation on hydrogeological problems, hoping to provide reference for the relative staff to carry out engineering geological investigation.Keywords: hydrogeology;engineering geological exploration;impact
基金This study was supported by the National Natural Science Foundation of China(U20A20148)the Major Science and Technology Projects of the Xizang(Tibet)Autonomous Region(XZ202201ZD0004G and XZ202201ZD0004G01).
文摘This research optimized the structure of lithium extraction solar ponds to enhance the crystallization rate and yield of Li_(2)CO_(3).Using the response surface methodology in Design-Expert 10.0.3,the authors conducted experiments to investigate the influence of four factors related to solar pond structure on the crystallization of Li_(2)CO_(3) and their pairwise interactions.Computational Fluid Dynamics(CFD)simulations of the flow field within the solar pond were performed using COMSOL Multiphysics software to compare temperature distributions before and after optimization.The results indicate that the optimal structure for lithium extraction from the Zabuye Salt Lake solar ponds includes UCZ(Upper Convective Zone)thickness of 53.63 cm,an LCZ(Lower Convective Zone)direct heating temperature of 57.39℃,a CO32−concentration of 32.21 g/L,and an added soda ash concentration of 6.52 g/L.Following this optimized pathway,the Li_(2)CO_(3) precipitation increased by 7.34% compared to the initial solar pond process,with a 33.33% improvement in lithium carbonate crystallization rate.This study demonstrates the feasibility of optimizing lithium extraction solar pond structures,offering a new approach for constructing such ponds in salt lakes.It provides valuable guidance for the efficient extraction of lithium resources from carbonate-type salt lake brines.
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This work was supported by the projects of the China Geological Survey(DD 20221703).
文摘Natural gas hydrate is a clean energy source with substantial resource potential.In contrast to conventional oil and gas,natural gas hydrate exists as a multi-phase system consisting of solids,liquids,and gases,which presents unique challenges and complicates the mechanisms of seepage and exploitation.Both domestic and international natural gas hydrate production tests typically employ a single-well production model.Although this approach has seen some success,it continues to be hindered by low production rates and short production cycles.Therefore,there is an urgent need to explore a new well network to significantly increase the production of a single well.This paper provides a comprehensive review of the latest advancements in natural gas hydrate research,including both laboratory studies and field tests.It further examines the gas production processes and development outcomes for single wells,dual wells,multi-branch wells,and multi-well systems under conditions of depressurization,thermal injection,and CO_(2) replacement.On this basis,well types and well networks suitable for commercial exploitation of natural gas hydrate were explored,and the technical direction of natural gas hydrate development was proposed.The study shows that fully exploiting the flexibility of complex structural wells and designing a well network compatible with the reservoir is the key to improving production from a single well.Moreover,multi-well joint exploitation is identified as an effective strategy for achieving large-scale,efficient development of natural gas hydrate.
基金This research was jointly supported by the China Geological Survey Project(DD20211404)the Natural Science Foundation of Inner Mongolia Autonomous Region(2019LH05028).
文摘With the development of the new energy industry and the depletion of nickel sulfide ore resources,laterite nickel ore has become the main source of primary nickel,and nickel for power batteries has become a new growth point in consumption.This paper systematically summarizes the processes,parameters,products,recovery rates,environmental indicators,costs,advantages,disadvantages and the latest research progress of mainstream nickel extraction processes from laterite nickel ore.It also provides a comparative analysis of the environmental impact and economic efficiency of different nickel extraction processes.It is found that the current nickel extraction processes from laterite nickel ore globally for commercial production mainly include the RKEF process for producing ferronickel and the HPAL process for producing intermediate products.The former accounts for about 80%of laterite nickel ore production.Compared to each other,the investment cost per ton of nickel metal production capacity for the RKEF is about 43000$,with an operational cost of about 16000$per ton of nickel metal and a total nickel recovery rate of 77%–90%.Its products are mainly used in stainless steels.For the HPAL process,the investment cost per ton of nickel metal production capacity is about 56000$,with an operational cost of about 15000$per ton of nickel metal and a total nickel recovery rate of 83%–90%.Its products are mainly used in power batteries.The significant differences between the two lies in energy consumption and carbon emissions,with the RKEF being 2.18 and 2.37 times that of the HPAL,respectively.Although the use of clean energy can greatly reduce the operational cost and environmental impact of RKEF,if RKEF is converted to producing high Ni matte,its economic and environmental performance still cannot match that of the HPAL and oxygen-enriched side-blown processes.Therefore,it can be inferred that with the increasing demand for nickel in power batteries,HPAL and oxygen-enriched side blowing processes will play a greater role in laterite nickel extraction.
基金supported by the Natural Science Foundation of China-Youth Foundation(42402163)Natural Science Foundation of Sichuan Province of China(2024NSFSC0814)Science and Technology Cooperation Project of the CNPC-SWPU Innovation Alliance(2020CX010101).
文摘The strike-slip fault system in the central Tarim Craton controls a complex petroleum system with estimated reserves exceeding 1×10^(9)t,the fault-related fractures are important for hydrocarbon accumulation.In this paper,the basic parameters such as density and width of fractures are counted and classified,and the effects of fractures on reservoirs are analyzed.The results show that:(1)Structural fractures and stylolite were widely developed in Halahatang area and experienced at least three stages of activity based on the infilling materials and crosscutting relationship.(2)Fracture density,width,aperture,and dip angle vary in different wells,but the relationship between the above parameters and the distance to the fault core indicates the fracture differences in the fault damage zone and further provides a method to divide the inner units in the fault damage zone.In addition,oil and gas wells with high production mainly concentrate in the inner unit.(3)The infilling materials and degree of fractures vary.Fractures formed in the early stage are more filled and less open,while the fractures formed in the late stage are relatively less filled and more open.(4)Fractures improve porosity to a certain extent but greatly increase permeability,especially in the inner zone of fault damage zone with large quantity,multiple inclinations,less filling and large width.These features contribute to the formation of a higher-quality reservoir,further improving oil and gas production.This paper provides a quantitative characterization method for the study of strike-slip fault-related fracture-caved reservoirs,and points out that fault damage zone,especially the inner zone of the fault damage zone,is the potential goal for oil and gas exploration.
