期刊文献+
共找到26篇文章
< 1 2 >
每页显示 20 50 100
Genetic Variation of Porcine Circovirus Type 2 Isolate 201105ZJ
1
作者 王小敏 何孔旺 +5 位作者 汪伟 周忠涛 杨光远 茅爱华 俞正玉 倪艳秀 《Agricultural Science & Technology》 CAS 2014年第11期1860-1864,1887,共6页
[Objective] This study aimed to investigate the genetic variation of porcine circovirus type 2 (PCV2) in China. [Method] The strain was isolated from infected samples by cel passage and preliminarily identified by P... [Objective] This study aimed to investigate the genetic variation of porcine circovirus type 2 (PCV2) in China. [Method] The strain was isolated from infected samples by cel passage and preliminarily identified by PCR and IFA. Ful-length genome of the isolated strain was obtained by specific amplification for homology and phylogenetic analysis. [Result] A PCV2 strain was successful y isolated and named 201105ZJ, which could proliferate in PK15 cel lines. Specific fragments could be amplified by specific PCR assay. According to results of IFA assay, specif-ic immunofluorescence was observed; the TCID50 was low (102.67); the ful-length genome sequence of the isolated strain was 1 768 bp, sharing 94.1%-96.8% ho-mology with 13 reference strains; to be specific, the isolated strain exhibited the highest homology of 96.8% with AF055392PCV2a; the isolated strain 201105ZJ and reference strain AF055392 belonged to genotype PCV2a, exhibiting a distant genetic relationship with genotype PCV2c. [Conclusion] Characteristics of genetic variation of PCV2 isolate 201105ZJ provided theoretical basis for vaccine development, investi-gation of PCV2 pathogenesis, and prevention and control of porcine circovirus-as-sociated diseases (PCVAD) in East China. 展开更多
关键词 Porcine circovirus type 2 Isolation Identification genetic variation
下载PDF
Geochemical Characteristics and Genetic Types of Natural Gas in the Xinchang Gas Field, Sichuan Basin, SW China 被引量:11
2
作者 WU Xiaoqi LIU Quanyou +5 位作者 LIU Guangxiang WANG Ping LI Huaji MENG Qingqiang CHEN Yingbin ZENG Huasheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第6期2200-2213,共14页
The molecular compositions and stable carbon and hydrogen isotopic compositions of natural gas from the Xinchang gas field in the Sichuan Basin were investigated to determine the genetic types. The natural gas is main... The molecular compositions and stable carbon and hydrogen isotopic compositions of natural gas from the Xinchang gas field in the Sichuan Basin were investigated to determine the genetic types. The natural gas is mainly composed of methane (88.99%-98.01%), and the dryness coefficient varies between 0.908 and 0.997. The gas generally displays positive alkane carbon and hydrogen isotopic series. The geochemical characteristics and gas-source correlation indicate that the gases stored in the 5th member of the Upper Triassic Xujiahe Formation are coal-type gases which are derived from source rocks in the stratum itself. The gases reservoired in the 4th member of the Xujiahe Formation and Jurassic strata in the Xinchang gas field are also coal-type gases that are derived from source rocks in the 3rd and 4th members of the Xujiahe Formation. The gases reservoired in the 2nd member of the Upper Triassic Xujiahe Formation are mainly coal-type gases with small amounts of oil-type gas that is derived from source rocks in the stratum itself. This is accompanied by a small amount of contribution brought by source rocks in the Upper Triassic Ma'antang and Xiaotangzi formations. The gases reservoired in the 4th member of the Middle Triassic Leikoupo Formation are oil-type gases and are believed to be derived from the secondary cracking of oil which is most likely to be generated from the Upper Permian source rocks. 展开更多
关键词 natural gas geochemical characteristics genetic types Xinchang gas field western Sichuan Basin
下载PDF
Genetic Types of Meter-Scale Cyclic Sequences and Fabric Natures of Facies Succession 被引量:14
3
作者 Mei Mingxiang Xu Debin Zhou Hongrui Institute of Earth Sciences and Natural Resources, China University of Geosciences, Beijing 100083 《Journal of Earth Science》 SCIE CAS CSCD 2000年第4期3-10,共8页
Different genetic types of meter-scale cyclic sequences in stratigraphic records result from episodic accumulation of strata related to Milankovitch cycles. The distinctive fabric natures of facies succession result f... Different genetic types of meter-scale cyclic sequences in stratigraphic records result from episodic accumulation of strata related to Milankovitch cycles. The distinctive fabric natures of facies succession result from the sedimentation governed by different sediment sources and sedimentary dynamic conditions in different paleogeographical backgrounds, corresponding to high-frequency sea-level changes. Naturally, this is the fundamental criterion for the classification of genetic types of meter-scale cyclic sequences. The widespread development in stratigraphic records and the regular vertical stacking patterns in long-term sequences, the evolution characters of earth history and the genetic types reflected by specific fabric natures of facies successions in different paleogeographical settings, all that show meter-scale cyclic sequences are not only the elementary working units in stratigraphy and sedimentology, but also the replenishment and extension of parasequence of sequence stratigraphy. Two genetic kinds of facies succession for meter-scale cyclic sequence in neritic-facies strata of carbonate and clastic rocks, are normal grading succession mainly formed by tidal sedimentation and inverse grading succession chiefly made by wave sedimentation, and both of them constitute generally shallowing upward succession, the thickness of which ranges from several tens of centimeters to several meters. The classification of genetic types of meter-scale cyclic sequence could be made in terms of the fabric natures of facies succession, and carbonate meter-scale cyclic sequences could be divided into four types: L-M type, deep-water asymmetrical type, subtidal type and peritidal type. Clastic meter-scale cyclic sequences could be grouped into two types: tidal-dynamic type and wave-dynamic type. The boundaries of meter-scale cyclic sequences are marked by instantaneous punctuated surface formed by non-deposition resulting from high-frequency level changes, which include instantaneous exposed punctuated surface, drowned punctuated surface as well as their relative surface. The development of instantaneous punctuated surface used as the boundary of meter-scale cyclic sequence brings about the limitations of Walter's Law on the explanation of facies distribution in time and space, and reaffirm the importance of Sander's Rule on analysis of stratigraphic records. These non-continuous surface could be traced for long distance and some could be correlative within same basin range. The study of meter-scale cyclic sequences and their regularly vertical stacking patterns in long-term sequences indicate that the research into cyclicity of stratigraphic records is a useful way to get more regularity from stratigraphic records that are frequently complex as well as non-integrated. 展开更多
关键词 genetic types fabric natures of facies succession meter-scale cyclic sequences.
下载PDF
Genetic types and distribution of shallow-buried natural gases 被引量:5
4
作者 Gao Yang Jin Qiang Zhu Guangyou 《Petroleum Science》 SCIE CAS CSCD 2010年第3期347-354,共8页
Great volumes of shallow-buried (〈2,000 m) natural gases which are mainly composed of biogases and low-mature gases have been found in the Mesozoic-Cenozoic sedimentary basins in China. Many shallow gas reservoirs ... Great volumes of shallow-buried (〈2,000 m) natural gases which are mainly composed of biogases and low-mature gases have been found in the Mesozoic-Cenozoic sedimentary basins in China. Many shallow gas reservoirs in China are characterized by coexistence of biogas and low-mature gas, so identifying the genetic types of shallow gases is important for exploration and development in sedimentary basins. In this paper, we study the gas geochemistry characteristics and distribution in different basins, and classify the shallow gas into two genetic types, biogas and low-mature gas. The biogases are subdivided further into two subtypes by their sources, the source rock-derived biogas and hydrocarbon-derived biogas. Based on the burial history of the source rocks, the source rock-derived biogases are divided into primary and secondary biogas. The former is generated from the source rocks in the primary burial stage, and the latter is from uplifted source rocks or those in a secondary burial stage. In addition, the identifying parameters of each type of shallow gas are given. Based on the analysis above, the distributions of each type of shallow gas are studied. The primary biogases generated from source rocks are mostly distributed in Quaternary basins or modem deltas. Most of them migrate in watersoluble or diffused mode, and their migration distance is short. Reservoir and caprock assemblages play an important role in primary biogas accumulation. The secondary biogases are distributed in a basin with secondary burial history. The oil-degraded biogases are distributed near heavy oil pools. The low-mature gases are widely distributed in shallow-buried reservoirs in the Meso-Cenozoic basins. 展开更多
关键词 Primary biogas secondary biogas oil-degraded biogas low-mature gas genetic type gas identification gas accumulation DISTRIBUTION
下载PDF
Rock Series and Genetic Types of Granitoids in the Western Kunlun Orogenic Belt,China 被引量:5
5
作者 JIANG Yaohui ZHOU Xunruo +3 位作者 RUI Xingjian GUO Kunyi HE Jurui YANG Wanzhi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2001年第1期19-26,共8页
A systematic geological and geochemical study was conducted for the granitoids of different periods in the western Kunlun orogenic belt. The study indicates that the granitoids belong to tholeiitic, calc-alkaline, hig... A systematic geological and geochemical study was conducted for the granitoids of different periods in the western Kunlun orogenic belt. The study indicates that the granitoids belong to tholeiitic, calc-alkaline, high-K calc-alkaline, alkaline and shoshonitic series, and that there are 5 genetic types, i.e., I-, S-, M-, A- and SH-type, of which SH-type is first put forward in this paper, which corresponds to shoshonitic granitoids. 展开更多
关键词 GRANITOID rock series genetic type western Kunlun orogenic belt
下载PDF
Current understandings of the pathogenesis of type 1 diabetes:Genetics to environment 被引量:3
6
作者 Adebola Matthew Giwa Rizwan Ahmed +5 位作者 Zahra Omidian Neha Majety Kagan Ege Karakus Sarah M Omer Thomas Donner Abdel Rahim A Hamad 《World Journal of Diabetes》 2020年第1期13-25,共13页
Type 1 diabetes(T1D)is an autoimmune disease that usually strikes early in life,but can affect individuals at almost any age.It is caused by autoreactive T cells that destroy insulin-producing beta cells in the pancre... Type 1 diabetes(T1D)is an autoimmune disease that usually strikes early in life,but can affect individuals at almost any age.It is caused by autoreactive T cells that destroy insulin-producing beta cells in the pancreas.Epidemiological studies estimate a prevalence of 1 in 300 children in the United States with an increasing incidence of 2%-5%annually worldwide.The daily responsibility,clinical management,and vigilance required to maintain blood sugar levels within normal range and avoid acute complications(hypoglycemic episodes and diabetic ketoacidosis)and long term micro-and macro-vascular complications significantly affects quality of life and public health care costs.Given the expansive impact of T1D,research work has accelerated and T1D has been intensively investigated with the focus to better understand,manage and cure this condition.Many advances have been made in the past decades in this regard,but key questions remain as to why certain people develop T1D,but not others,with the glaring example of discordant disease incidence among monozygotic twins.In this review,we discuss the field’s current understanding of its pathophysiology and the role of genetics and environment on the development of T1D.We examine the potential implications of these findings with an emphasis on T1D inheritance patterns,twin studies,and disease prevention.Through a better understanding of this process,interventions can be developed to prevent or halt it at early stages. 展开更多
关键词 Type 1 diabetes genetics Type 1 diabetes epigenetics Role of genetics in type 1 diabetes Diabetes prevention Type 1 diabetes environment Type 1 diabetes twin studies Type 1 diabetes concordance Type 1 diabetes discordance
下载PDF
Genetic types and geochemicai characteristics of natural gases in the Jiyang Depression,China
7
作者 Wen-Tao Li Yang Gao Chun-Yan Geng 《Petroleum Science》 SCIE CAS CSCD 2015年第1期81-95,共15页
Natural gases were widely distributed in the Jiyang Depression with complicated component composition, and it is difficult to identify their genesis. Based on investigation of gas composition, carbon isotope ratios, l... Natural gases were widely distributed in the Jiyang Depression with complicated component composition, and it is difficult to identify their genesis. Based on investigation of gas composition, carbon isotope ratios, light hydrocarbon properties, as well as geological analysis, natural gases in the Jiyang Depression are classified into two types, one is organic gas and the other is abiogenic gas. Abiogenic gas is mainly magmatogenic or mantlederived CO2. Organic gases are further divided into coaltype gas, oil-type gas, and biogas according to their kero- gen types and formation mechanisms. The oil-type gases are divided into mature oil-type gas (oil-associated gas) and highly mature oil-type gas. The highly mature oil-type gases can be subdivided into oil-cracking gas and kerogen thermal degradation gas. Identification factors for each kind of hydrocarbon gas were summarized. Based on genesis analysis results, the genetic types of gases buried in different depths were discussed. Results showed that shallow gases (〈1,500 m) are mainly mature oil-type gases, biogas, or secondary gases. Secondary gases are rich in methane because of chromatographic separation during migration and secondary biodegradation. Secondary biodegradation leads to richness of heavy carbon isotope ratios in methane and propane. Genesis of middle depth gases (1,500-3,500 m) is dominated by mature oil-type gases.Deep gases (3,500-5,500 m) are mainly kerogen thermal degradation gas, oil-cracking gas, and coal-type gas. 展开更多
关键词 genetic types Natural gases Jiyang Depression Light hydrocarbon properties Carbon isotope ratios Identification factors
下载PDF
Genetic Types and Distribution of CO_2 Gases in the Huanghua Depression
8
作者 JinZhenkui BaiWuhou ZhangXiangxiang 《Petroleum Science》 SCIE CAS CSCD 2005年第2期25-30,共6页
CO2 gas is a nonhydrocarbon gas, with a high economic value and a broad prospect for application. In the Huanghua Depression, there exist many genetic types of CO2 gases, i.e. organic CO2, thermal metamorphic CO2 and ... CO2 gas is a nonhydrocarbon gas, with a high economic value and a broad prospect for application. In the Huanghua Depression, there exist many genetic types of CO2 gases, i.e. organic CO2, thermal metamorphic CO2 and crust-mantle mixed CO2. The distribution of different types of CO2 gases is controlled by different factors. Organic CO2 that occurs mainly around the oil-generating center is associated with hydrocarbon gases as a secondary product and commonly far away from large faults. Thermal metamorphic CO2 occurs mainly in areas where carbonate strata are developed and igneous activity is strong, and tends to accumulate near large faults. CO2 of such an origin is higher in concentration than organic CO2, but lower than crust-mantle mixed CO2. Crust-mantle mixed CO2 occurs mainly along large faults. Its distribution is limited, but its purity is the highest. 展开更多
关键词 Huanghua Depression CO2 gas ORIGIN genetic types DISTRIBUTION
下载PDF
Geology,Genetic Types and Metallogeny of Gold Deposits in the Eastern Tianshan,Xinjiang
9
作者 FENG Jianzhong ZENG Yishan FU Shuixing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第3期559-564,共6页
As a typical Palaeozoic island arc system, the eastern Tianshan area, Xinjiang, is different from eastern China but similar to the Meso-Cenozoic island arc metallogenic provinces along the coast of the Pacific Ocean i... As a typical Palaeozoic island arc system, the eastern Tianshan area, Xinjiang, is different from eastern China but similar to the Meso-Cenozoic island arc metallogenic provinces along the coast of the Pacific Ocean in metallogenic environment, geology and geochemistry. Three types of gold deposits, ductile shear zone-hosted gold deposits (Kanggur'), magmatic hydrothermal gold deposits (Jinwozi) and volcanic- or subvolcanic-hosted gold deposits (Xitan and Mazhuangshan), have been identified in this area. Regionally, gold deposits are structurally controlled by the Kanggur Tag ductile shear zone, Shaquanzi fault, Hongliuhe fault and Yamansu fault. Generally, gold mineralization occurs in the transition zones from volcanic rocks to sedimentary rocks. The horizon bearing well-developed jasper is an important indicator for gold mineralization. Each of the three types of gold deposits has its distinctive metallogenic background and geological-geochemical characteristics. 展开更多
关键词 eastern Tianshan GOLD METALLOGENY genetic type GEOLOGY GEOCHEMISTRY
下载PDF
Carbon isotopic composition and genetic types of natural gas in the Sichuan Basin, China
10
作者 Jin-ning peng Dong-yan Wang +2 位作者 Guang-xiang Liu Min Zhang Feng-li Li 《Acta Geochimica》 EI CAS CSCD 2017年第1期102-111,共10页
The origin and genetic types of natural gas in the Sichuan Basin are still disputed.To classify the origin and genetic types in different areas,the paper analyzes the carbon isotopic composition of gases and geologic ... The origin and genetic types of natural gas in the Sichuan Basin are still disputed.To classify the origin and genetic types in different areas,the paper analyzes the carbon isotopic composition of gases and geologic features in the Sichuan Basin.The results showed that the gas sourced from terrestrial layers is typically characterized by terrestrial origin and was mainly accumulated nearby to form reservoir.The carbon isotopic composition of gas showed a normal combination sequence distribution,suggesting that natural gas in continental strata is not affected by secondary alteration or that this deformation is very weak.The gas source is singular,and only gas from the southern and northern Sichuan Basin shows the characteristic of mixed sources.However,marine gas presents the characteristics of an oil-formed gas.The carbon isotopic composition of natural gas in the western and central part of the basin mostly distributes in a normal combination sequence,and few of them showed an inversion,indicating that the gas perhaps had not experienced secondary alteration.The carbon isotopic composition of marine-origin gas in the southern,northern and eastern Sichuan Basin displays a completely different distribution pattern,which is probably caused by different mixing ratio of gas with multi-source and multi-period. 展开更多
关键词 The Sichuan Basin ALKANE Carbon isotope genetic type
下载PDF
Semen characteristics of the three genetic types of boars reared in Benin
11
作者 Ignace O.Dotché Aichatou Gakou +7 位作者 Constant Boris O.B.Bankolé Mahamadou Dahouda Isidore Houaga Nicolas Antoine-Moussiaux Jean Paul Dehoux Pierre Thilmant Benoit G.Koutinhouin Issaka Youssao Abdou Karim 《Asian pacific Journal of Reproduction》 2021年第2期82-89,共8页
Objective:To characterize the semen of three genetic types of boars(local,improved and Large White)reared in Benin.Methods:Semen of local,improved and Large White boars reared in Benin were collected using the gloved ... Objective:To characterize the semen of three genetic types of boars(local,improved and Large White)reared in Benin.Methods:Semen of local,improved and Large White boars reared in Benin were collected using the gloved hand method and analyzed to determine volume,pH,concentration,mobility,motility,and morphology.The effect of the genetic type of boar on semen characteristics was aslo studied.Results:Duration of ejaculation and semen volume of Large White boar were significantly higher than those of local and improved boars(P<0.05).The semen of improved boars had a higher motility score than that of Large White and local boars(P<0.001).The semen of local boars was more concentrated in the spermatozoa than that of improved and Large White boars(P<0.05).The proportion of spermatozoa of improved boars with normal morphology(93.6%)was significantly higher than that of local(82.2%)and Large White boars(81.6%)(P<0.001).The proportion of spermatozoa with folded tails in the semen of Large White boars(9.2%)was significantly higher than that observed in improved(1.8%)and local(5.0%)boars(P<0.001).The proportion of spermatozoa with proximal cytoplasmic droplets in semen of improved boars(2.7%)was significantly lower than that in Large White(6.8%)and local(9.7%)boars(P<0.001).The local(1.5%)and Large White boars(1.1%)showed more spermatozoa with distal cytoplasmic droplets in their semen compared to the improved boars(0.4%).Conclusions:The semen characteristics of pigs reared in Benin vary from one genetic type to another.Each genetic type has a strong point.The Large White boar produces larger semen,the local boar produces more concentrated semen and the improved boar produces spermatozoa that are morphologically better.The semen of these three genetic types can be used in artificial insemination but the improved boar's semen is more recommended. 展开更多
关键词 BOARS SEMEN Local pigs BENIN Semen characteristics genetic types
下载PDF
Human a Type Genetic Engineering Interference Essence Injection
12
《China's Foreign Trade》 1995年第2期46-46,共1页
The highest-level interference essence against virus and turnour genetic engineering medicine is a new type created in the 1980s. Compared with chemical medicines, the interference essence has a special effect in the ... The highest-level interference essence against virus and turnour genetic engineering medicine is a new type created in the 1980s. Compared with chemical medicines, the interference essence has a special effect in the treatment of viruses and tumours. The human a, type genetic engineering interference essense is prepared by the Institute of Viruses of the Chinese Academy of Preventive Medical Sciences, the Shanghai Vaccine 展开更多
关键词 Human a Type genetic Engineering Interference Essence Injection
下载PDF
PATERNITY IDENTIFICATION ON ABORTED FETAL MATERIAL
13
作者 李生斌 李小明 《Journal of Pharmaceutical Analysis》 CAS 1995年第2期169-172,共4页
After a rape, woman who is pregnamt often elect to abort the fetus.The authors describe 2 cases witers genetic markers ABO, MN,Rh,PGM1,EsD,ACP,GLOI,GPT,HP,Cc and HLA-A,-B were tasted on the aborted fetal material to p... After a rape, woman who is pregnamt often elect to abort the fetus.The authors describe 2 cases witers genetic markers ABO, MN,Rh,PGM1,EsD,ACP,GLOI,GPT,HP,Cc and HLA-A,-B were tasted on the aborted fetal material to provide evidence of the genetic constitution of the rapist The results showed that this type of testing is possible for prenatal paternity identification. 展开更多
关键词 paternity identification genetic typing criminal sex offenses
下载PDF
Coalbed methane genesis, occurrence and accumulation in China 被引量:31
14
作者 Song Yan Liu Shaobo +3 位作者 Zhang Qun Tao Mingxin Zhao Mengjun Hong Feng 《Petroleum Science》 SCIE CAS CSCD 2012年第3期269-280,共12页
Coalbed methane (CBM) is an important type of unconventional gas. Commercial development of CBM in America has been very successful since the 1980s. The CBM industry in Australia and Canada has developed rapidly dur... Coalbed methane (CBM) is an important type of unconventional gas. Commercial development of CBM in America has been very successful since the 1980s. The CBM industry in Australia and Canada has developed rapidly during the last decade. Commercial development of CBM in China started in the 1990s, and has made great progress. The geological theory of CBM in China has achieved great advancement in genesis, occurrence and accumulation. On the aspect of CBM genesis, five CBM genetic types (primary biogenic gas, secondary biogenic gas, thermal degradation gas, pyrolysis gas and mixed gas) are identified by studying the geochemical characteristics of CBM, and a tracing indicator system is established. The discovery of secondary biogenic gas in medium-high rank coal reservoirs has widened the potential of CBM resources. On the aspect of CBM occurrence, the gas adsorption regulation under combined action of temperature and pressure is revealed by conducting adsorption experiments of different coal ranks under varying temperature and pressure conditions. Besides, by applying the adsorption potential theory in CBM research, the adsorption model under combined action of temperature and pressure is established. The new model can predict CBM resources accurately, and overcome the limitation of the traditional Langmuir model which uses just a single factor to describe the adsorption characteristics of deep buried coal. On the aspect of CBM accumulation, it is proposed that there are three evolutionary stages during CBM accumulation, including gas generation and adsorption, unsaturated gas adsorption, gas desorption-diffusion and preservation. Controlled by tectonic evolution, hydrodynamics and sealing conditions, CBM tends to be regionally enriched in synclines. Advances in geological theory of CBM in China can not only improve understanding of natural gas, but also provide new ideas for further exploration of CBM. 展开更多
关键词 China coalbed methane genetic type secondary biogenic gas adsorption model syncline enrichment
下载PDF
Research on Formation Mechanisms of Hot Dry Rock Resources in China 被引量:18
15
作者 WANG Guiling LIN Wenjing +3 位作者 ZHANG Wei LU Chuan MA Feng GAN Haonan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第4期1418-1433,共16页
As an important geothermal resource, hot dry rock (HDR) reserves have been studied in many countries. HDR resources in China have huge capacity and have become one of the most important resources for the potential r... As an important geothermal resource, hot dry rock (HDR) reserves have been studied in many countries. HDR resources in China have huge capacity and have become one of the most important resources for the potential replacement of fossil fuels. However, HDR resources are difficult to develop and utilise. Technologies for use with HDR, such as high-temperature drilling, reservoir characterisation, reservoir fracturing, microseismic monitoring and high-temperature power stations, originate from the field of oil and drilling. Addressing how to take advantage of these developed technologies is a key factor in the development of HDR reserves. Based on the thermal crustal structure in China, HDR resources can be divided into four types: high radioactive heat production, sedimentary basin, modern volcano and the inner-plate active tectonic belt. The prospective regions of HDR resources are located in South Tibet, West Yunnan, the southeast coast of China, Bohai Rim, Songliao Basin and Guanzhong Basin. The related essential technologies are relatively mature, and the prospect of HDR power generation is promising. Therefore, analysing the formation mechanisms of HDR resources and promoting the transformation of technological achievements, large-scale development and the utilisation of HDR resources can be achieved in China. 展开更多
关键词 HDR resources drilling technique genetic type resources distribution develop prospect
下载PDF
A synthesis of iron deposits in the eastern Tianshan,NW China 被引量:5
16
作者 Jiahao Zheng 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第4期1271-1287,共17页
The northern Xinjiang region is one of the most significant iron metallogenic provinces in China.Iron deposits are found mainly within three regions:the Altay,western Tianshan,and eastern Tianshan orogenic belts.Previ... The northern Xinjiang region is one of the most significant iron metallogenic provinces in China.Iron deposits are found mainly within three regions:the Altay,western Tianshan,and eastern Tianshan orogenic belts.Previous studies have elaborated on the genesis of Fe deposits in the Altay orogenic belt and western Tianshan.However,the geological characteristics and mineralization history of iron deposits in the eastern Tianshan are still poorly understood.In this paper I describe the geological characteristics of iron deposits in the eastern Tianshan,and discuss their genetic types as well as metallogenic-tectonic settings,Iron deposits are preferentially distributed in central and southern parts of the eastern Tianshan.The known iron deposits in the eastern Tianshan show characteristics of magmatic Fe-Ti-V(e.g.,Weiya and Niumaoquan),sedimentary-metamorphic type(e.g.,Tianhu),and iron skarn(e.g.,Hongyuntan).In addition to the abovementioned iron deposits,many iron deposits in the eastern Tianshan are hosted in submarine volcanic rocks with well-developed skarn mineral assemblages.Their geological characteristics and magnetite compositions suggest that they may belong to distal skarns.SIMS zircon U-Pb analyses suggest that the Fe-Ti oxide ores from Niumaoquan and Weiya deposits were formed at 307.7±1.3 Ma and 242.7±1.9 Ma,respectively.Combined with available isotopic age data,the timing of Fe mineralization in the eastern Tianshan can be divided into four broad intervals:Early Ordovician-Early Silurian(476-438 Ma),Carboniferous(335-303 Ma),Early Permian(295-282 Ma),and Triassic(ca.243 Ma).Each of these episodes corresponds to a period of subduction,post-collision,and intraplate tectonics during the Paleozoic and Mesozoic time. 展开更多
关键词 Iron deposits Geological characteristics Ore-forming ages genetic types Eastern Tianshan
下载PDF
Application of butane geochemistry of natural gas in hydrocarbon exploration 被引量:4
17
作者 Miao Zhongying Chen Jianfa +3 位作者 Wang Jing Wang Guannan ZhangChen Li Wei 《Petroleum Science》 SCIE CAS CSCD 2012年第4期455-462,共8页
In order to distinguish the source and migration direction of natural gas by geochemical characteristics of butane,the components and carbon isotopes of natural gas from major hydrocarbonbearing basins in China were a... In order to distinguish the source and migration direction of natural gas by geochemical characteristics of butane,the components and carbon isotopes of natural gas from major hydrocarbonbearing basins in China were analyzed.The results showed that:(1) Oil-type gas has i-C 4 /n-C 4 0.8,δ 13 C butane -28‰,δ 13 C i-butane -27‰,δ 13 C n-butane -28.5‰,whereas coal-type gas has i-C 4 /n-C 4 0.8,δ 13 C butane -25.5‰,δ 13 C i-butane -24‰,δ 13 C n-butane -26‰.(2) When δ 13 C i-butane-δ 13 C n-butane is greater than 0,the maturity of oil-type gas is generally more than 2.4% and that of coal-type gas is greater than 1.4%,whereas when the difference is less than 0,the maturity of oil-type gas is generally less than 1.1% and that of coal-type gas is less than 0.8%.(3) When natural gas migrates through dense cap rocks,the value of i-C 4 /n-C 4 increases,whereas when it migrates laterally along a reservoir,the value of i-C 4 /n-C 4 decreases.(4) Sapropelic transition zone gas with composition and carbon isotopic signatures similar to those of oil-type gas in the low thermal evolution stage is found to have a relatively high butane content.(5) The values of i-C 4 /n-C 4 and δ 13 C n-butane δ 13 C i-butane of gas which has suffered biological degradation are significantly higher than those obtained from thermogenic and bio-thermocatalytic transition zone gas.Thus,natural gas of different genetic types can be recognized through component analysis and carbon isotopic signatures of butane,the natural gas maturity can be estimated from the difference in carbon isotopic content between isobutane and n-butane,and the migration direction of natural gas can be determined from i-C 4 /n-C 4 ratios and transport conditions,which can also be used to thermogenic and bio-thermocatalytic transition zone gas. 展开更多
关键词 Natural gas N-BUTANE ISOBUTANE carbon isotope genetic types of natural gas migration direction
下载PDF
Dynamic Systems of Petroleum Accumulation in the Nanpu Depression,Bohai Bay Basin,China 被引量:3
18
作者 LIU Guangdi SUN Mingliang +1 位作者 ZHANG Zhihuan DONG Yuexia 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第5期1273-1285,共13页
It is significant to distinguish the dynamic systems of petroleum accumulation (DSPA) for the understanding of petroleum accumulation and distribution. According to the formation pressure framework, genetic types of... It is significant to distinguish the dynamic systems of petroleum accumulation (DSPA) for the understanding of petroleum accumulation and distribution. According to the formation pressure framework, genetic types of petroleum and characteristics of conduit systems, three dynamic systems of petroleum accumulation were identified in the vertical profile in the Nanpu depression, Bohai Bay basin. The deeper DSPA (including formations Es3 to Es2) is a sealed system with high-overpressure and high-mature self-sourced oil. Most of the crude oil in the system accumulated in the periods of late Oligocene (23.5 Ma) and late Pliocene (2.4 Ma). The middle DSPA (including formations Es~ to Edl) is an overpressured half-sealed system with mature or lower-mature self-sourced oil. The accumulation of oil in the system also occurred in the late Oligocene (23.5 Ma) and late Pliocene (2.4 Ma). The shallower DSPA (including formations Ed2 to Q) is a hydrostatic system with lower-mature aliensourced oil from the middle system. Oil within this system accumulated only in the late Pliocene period. The oil in the shallower system migrated vertically along the faults from the formerly accumulated oil in the middle system by lateral migration along the sandbodies, whereas petroleum accumulation in the deeper system was mainly derived from the system itself by lateral migration along the sandbodies and rarely migrated out of the system. In this case, it seems that the deeper system is a more potential exploration prospect in addition to the other two proved favorable systems. 展开更多
关键词 dynamic system of petroleum accumulation genetic types of petroleum pressureframework accumulation process Nanpu depression
下载PDF
Geochemical Characteristics and Gas-to-Gas Correlation of Two Leakage-type Gas Hydrate Accumulations in the Western Qiongdongnan Basin, South China Sea 被引量:3
19
作者 LAI Hongfei QIU Haijun +4 位作者 LIANG Jinqiang KUANG Zenggui FANG Yunxin REN Jinfeng LU Jing’an 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第2期680-690,共11页
In recent years,a series of highly saturated leakage-type gas hydrates have been discovered in the western Qiongdongnan Basin(QDNB),South China Sea.Based on the molecular compositional and isotopic characteristics of ... In recent years,a series of highly saturated leakage-type gas hydrates have been discovered in the western Qiongdongnan Basin(QDNB),South China Sea.Based on the molecular compositional and isotopic characteristics of the gas samples relevant to the gas hydrates collected from the two leakage-type gas hydrate accumulations in the GMGS5 and GMGS6 drilling zones,a detailed geochemical gas-to-gas correlation was conducted in this study,in order to further understand the geochemical characteristics and possible hydrocarbon sources of these gas hydrates.The natural gas relevant to the gas hydrates in the GMGS5 block is characterized by wet gas(67.96%<%C_(1)<98.58%,C_(1)/C_(1+)<0.9)and significant molecular and carbon isotope fractionation within the depth profile,whereas the gas samples from the GMGS6 block exhibit the characteristics of dry gas(99.25%<%C_(1)<99.81%,C_(1)/C_(1+)>0.9)and lack molecular and carbon isotope fractionation.Approximately 40%‒60%of the methane within the gas hydrate is of microbial origin,while the C^(2+)gas components are typical coal-type gas that are derived from thermogenic source rocks or deeply-buried natural gas fields.In addition,typical in situ primary microbial methane(−80.6‰<δ^(13)C-C_(1)<−67.7‰)was discovered in well W b,which was applied to estimate the contribution of the microbial gas to the gas hydrates.The gas-to-gas correlation results show that the hydrate gases within the two leakage-type gas hydrate accumulations in the GMGS5 and GMGS6 blocks are geochemically different,suggesting that they may have been derived from different source kitchens.Our results further indicate that the deeply-buried thermogenic gas significantly contributed to the shallowly-buried gas hydrates in the western QDNB and multiple effective thermogenic source kitchens provided the hydrocarbon gas in the gas hydrate accumulations. 展开更多
关键词 gas hydrate gas genetic type hydrocarbon gas source geochemical characteristics
下载PDF
GEOCHEMICAL CHARACTERISTICS OF STABLE ISOTOPES FROM HYDROTHERMAL CHIMNEYS IN THE MARIANA TROUGH, WEST PACIFIC OCEAN 被引量:1
20
作者 吴世迎 张道建 +2 位作者 王揆洋 陈成业 白黎明 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2000年第4期378-384,共7页
The determination of the stable isotopes, δD, δ18 and δ30, values from hydrothermal chimneys in the Mariana Trough, the West Pacific, indicated that the pure siliceous chimneys with gentle data variation were forme... The determination of the stable isotopes, δD, δ18 and δ30, values from hydrothermal chimneys in the Mariana Trough, the West Pacific, indicated that the pure siliceous chimneys with gentle data variation were formed in low temperature environment. It reflects that the sea-floor hydrothermal activity of the Mariana Trough is primarily low-to-medium temperature hydrothermal eruption, and those chimneys with strong data variation and containing pyrite were formed in higher temperature environment. Key words Mariana Trough - stable isotope - geochemistry - hydrothermal chimney - genetic type Project 49876016 supported by NSFC. 展开更多
关键词 Mariana Trough stable isotope geochemistry hydrothermal chimney genetic type
下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部