Geochemical Characteristics and Origin of Natural Gases in the Qaidam Basin, China   总被引：5，自引：0，他引：5  

ZHANG Xiaobao  HU Yong  DUAN Yi  MA Liyuan  MENG Zifang  HE Peng  ZHOU Shixin  PENG DehuaState Key Laboratory of Gas Geochemistry  Lanzhou Institute of Geology  Chinese Academy ofSciences  Lanzhou  Gansu  Research Institute of Petroleum Exploration  Development  Qinghai Petroleum Company  CNPC  Dunhuang  Gansu 《《地质学报》英文版》2003,77(1):103-115

Sixty-five natural gas samples were collected from 19 oil-gasfields in the Qaidam basin, China. The chemical composition and carbon isotope values of the samples were measured, and the geochemical characteristics and origin of the natural gases were studied. The gases can be divided into biogenic gases, sapropelic oil-type gases, mixed type oil-type gases, coal-type gases and mixed gas. The δ13Ci values of the biogenic gases are very small and the C2+ contents of them are very low, ranging from -68.2‰ to -61.8‰ and 0.06% to 0.20% respectively. They have heavy δD and δ13Cco2> showing a CC>2 reduction pathway. They are distributed in the East depression region and derived from the Quaternary source rocks. The sapropelic oil-type gases have small δ13C2 values and high C2+ ranging from -36.6‰ to -28.6‰ and from 33.01% to 47.15% respectively. The mixed type oil-type gases have <5I3C2 values and C2+ contents varying from -28.6‰ to -24.8‰ and from 4.81% to 26.06% respectively. Both sapropelic oil-typ  相似文献   

吐哈盆地西部地区高蜡凝析油和轻质油的地球化学特征及成因分析   总被引：3，自引：2，他引：3  

张枝焕  黄志龙  张振英  朱丹  王铁冠 《地质学报》2004,78(4):551-559

吐哈盆地西部地区中、新生界储层中广泛分布着轻质油和凝析油。这些原油具有低密度、低粘度、中等—高含蜡量的特点 ,含蜡量为 5 .5 %～ 2 2 .1% ,高分子量正构烷烃 (n C35～ n C87)含量较高 ,属中—高蜡轻质油或凝析油 ,其地球化学特征及成因机理既不同于常规的高蜡原油 ,又不同于一般意义上的凝析油。吐哈盆地中、新生界高蜡凝析油或轻质油主要来源于侏罗系湖相泥岩和煤系地层中泥岩或煤 ,其形成主要取决于烃源岩的有机显微组分和有机质演化程度。研究区侏罗系湖相泥岩和煤系地层泥岩或煤岩中有机显微组分均以镜质组和壳质组为主 ,壳质组中角质体和木栓质体含量较高 ,具备了既可形成凝析油 ,又可形成高蜡油的条件。由于镜质组与部分壳质组演化形成烃类化合物的活化能相当 ,因此又具备高蜡油与凝析油共生的地球化学条件  相似文献   

流体动力系统对流体包裹体均一温度的影响及其意义——以准噶尔盆地陆东地区为例   总被引：10，自引：3，他引：10  

康永尚邱楠生  刘洛夫文永红张越迁  姚新玉张年富 王绪龙 《地质学报》2004,78(5):704-709

在准噶尔盆地陆东地区 ,纵向上存在两个流体动力系统 ,即下部高压流体动力系统和中上部正常 -低压流体动力系统 ,对下部高压流体动力系统 ,流体包裹体均一温度可用来确定油气成藏期 ,而对中上部正常 -低压流体动力系统 ,流体包裹体均一温度不适于用来确定油气成藏期 ,这主要由包裹体捕获时的流体动力学环境和相态不同所致。高压流体动力学环境中形成的包裹体在捕获时更易呈均一相 ,包裹体的均一温度可有效用于成藏期的判定 ,而在正常 -低压系统中形成的包裹体在捕获时有呈非均一相的可能 ,在此情况下 ,流体包裹体均一温度就无法用于成藏期的确定 ,在用包裹体均一温度判定成藏期时 ,结合具体的地质条件做具体分析是十分必要的。  相似文献   

东南沿海地区新生代火山作用和地幔柱   总被引：17，自引：0，他引：17  

赵海玲狄永军  刘振文李剑邓晋福  何恭算刘清华 《地质学报》2004,78(6):781-788

通过本文的研究表明 ,东南沿海地区从沿海→内陆 (牛头山→闽清→明溪 )新生代玄武岩的年龄逐渐变小 ,具有火山链的特征 ;微量元素和 Sr- Nd同位素特征与洋岛玄武岩 (OIB)类似 ;上地幔具有过热状态和扰动的热结构 ;地球物理具有低的 Vs 异常及提供了在该区下面具有地幔柱的 CT模式 ;火山岩具有较高的 3He/4He同位素比值 ,因此提出了研究区下面存在地幔柱。进一步根据火山岩的热动力学参数 ,从沿海→内陆 ,随火山岩年龄变小 ,火山岩的碱性程度逐渐增加 ,岩浆起源的深度逐渐变深 ,局部熔融程度逐渐变小等特征 ,提出了地幔柱的形成是由太平洋板块俯冲诱发 ,地幔柱位于俯冲带上面 ,南海的扩张和新生代火山岩的形成是地幔柱作用的结果 ,并提出地幔柱成因演化模式。  相似文献   

Dynamic Features of Angular Unconformity Formation——Extensional and Compressional Angular Unconformities   总被引：3，自引：0，他引：3  

LI Zhongquan  XU Shihai  YING Danlin  Han Jianhui State Key Loboratory of Oil  Gas Reservoir Geology  Exploration  Chengdu University ofTechnology  Chengdu  Sichuan  PetroChina Company Limited Southwest Oil  Gas Field Company Exploration  Development Research Institute  Chengdu  Sichuan 《《地质学报》英文版》2004,78(1):298-301

Angular unconformity is one of the most direct and strongest evidences for approving the tectonic movements of the earth's crust. Its dynamic genesis process has been understood to be mainly related to the compressional setting for a long time. Especially, in a detailed structural analysis for a specific region, when an angular unconformity is discovered people would regard it as the result of orogenic movements of a certain period or a certain episode and neglect the extensional facts. Based on a dialectical point of view of extension-compression, this paper has proved that angular unconformities can be formed not only in compressional settings, but also in extensional ones. Further more, their geological features are compared and he possible genetic mechanisms for angular unconformity under different dynamic settings are studied.  相似文献   

LAND DEGRADATION AND ITS CONTROL STRATEGIES IN CHINA   总被引：1，自引：0，他引：1  

Yang Chaofei Dapartment of Natural Conservation  National Environmental Protection Agency  Beijing People''s Republic of China 《地理学报(英文版)》1997,(2)

Ｈｕｍａｎ-ｉｎｄｕｃｅｄｌａｎｄｄｅｇｒａｄａｔｉｏｎａｓａｃｅｎｔｒａｌｔｈｅｍｅｏｆｄｅｓｅｒｔｉｆｉｃａｔｉｏｎｉｎｔｈｅｗｏｒｌｄｒｅｆｅｒｓｔｏｄｅｃｌｉｎｅｏｒｌｏｓｓｏｆｂｉｏｌｏｇｉｃａｌｏｒｅｃｏｎｏｍｉｃｐｒｏｄｕｃｔｉｖｉｔｙｃａｕｓｅｄｂｙｉｒｒａｔｉｏｎａｌｈｕｍａｎａｃｔｉｖｉｔｉｅｓ.ＡｃｃｏｒｄｉｎｇｔｏａｓｓｅｓｓｍｅｎｔｏｆＵＮＥＰａｂｏｕｔ3.6ｂｉｌｌｉｏｎｈａｏｆｌａｎｄｉｎｏｖｅｒｏｎｅｈｕｎｄｒｅｄｃｏｕｎｔｒｉｅｓｈａｖｅｂｅｅｎａｆｆｅｃｔｅｄｂｙ…  相似文献   

THE IMPACTS OF GLOBAL CHANGE ON DESERTIFICATION IN CHINA     

Ci Longjun Commission for Integrated Survey of Natural Resources  CAS  Beijing People''s Republic of China 《地理学报(英文版)》1997,(3)

ＩｎＣｈｉｎａ,ｄｅｓｅｒｔｓｍｏｖｉｎｇｎｏｒｔｈｗａｒｄｄｕｅｔｏｔｈｅｕｐｌｉｆｔｉｎｇｏｆｔｈｅＱｉｎｇｈａｉ-ＴｉｂｅｔＰｌａｔｅａｕａｒｅｄｉｓｔｒｉｂｕｔｅｄｉｎａｒｉｄ,ｓｅｍｉ-ａｒｉｄａｎｄｄｒｙｓｕｂ-ｈｕｍｉｄａｒｅａｓｏｆ35°-50°Ｎａｎｄ75°-125°Ｅ.Ｄｅｓｅｒｔｓ,ＧｏｂｉａｎｄｄｅｓｅｒｔｉｆｉｃａｔｉｏｎａｆｆｅｃｔｅｄａｒｅａｓｈｏｒｉｚｏｎｔａｌｌｙｃｒｏｓｓｅｄＮｏｒｔｈｗｅｓｔ,ＮｏｒｔｈａｎｄＮｏｒｔｈｅａｓｔＣｈｉｎａｉｎａｌｅｎｇｔｈｏｆ4,500ｋｍ.Ｔｈｅｖ…  相似文献   

MODELING SEDIMENT PROCESSES ON SMALL WATERSHEDS: A CONCEPTUAL FRAMEWORK Ⅱ. CONCENTRATED FLOW PROCESSES     

Vicente L. LOPES  Peter F. FFOLLIOTT Assistant Professor  School of Renewable Natural Resources  The University of Arizona. Tucson. Arizona. Professor  School of Renewable Natural Resources. The University of Arizona  Tucson. Arizona. 《国际泥沙研究》1993,(1)

L INTRODUCTIONThe purpose of this paper is to present a general modeling framework that can serveas a conceptual basis for developing sediment process models by concentrated flow systems on small watersheds. A survey of fundamental principles for developing sedimentprocess models is made with particular emphasis on the effects of space and time averaging on the governing equations. Starting from the most general one--dimensional,unsteady model of sediment processes, simpler model structur…  相似文献   

中国油气资源战略选区若干问题的思考     

张大伟 《地质通报》2006,(Z2)

在中国油气资源供需矛盾日趋尖锐、形势越来越严峻的情况下,开展全国油气资源战略选区工作、加强油气资源战略调查与早期评价具有重要意义。近些年来国家围绕青藏地区、柴达木盆地、松潘—阿坝地区、东北中—新生代断陷盆地群、华北前第三系、南海北部陆坡深水海域、南黄海海域前第三系、中国煤层气开发利用前景等开展的战略选区项目,取得了一定的成果和认识。就战略选区的定位、任务和特点进行了论述,分析了未来选区的工作重点并提出了相应的措施,对促进战略选区工作具有指导意义。  相似文献   

High Temperature as a Mechanism for Plant Cytoplasm Preservation in Fossils          下载免费PDF全文

WANG Xin 《《地质学报》英文版》2007,81(2):183-193

Because the cytoplasm of a plant normally degrades after the death of the plant, finding cytoplasm in a plant body after a prolonged period of time, especially in fossil plants, is unexpected. Recent work on several 100-Myr-old plant fossils from Kansas, USA indicates, however, that cells and their contents can be preserved. Most of the cells in these fossil plants appear to be in a state of plasmolysis, and these fossil cells bear a strong resemblance to laboratory-baked cells of extant plant tissues. Based on a comparison with extant material plus biophysical and biochemical analyses of the cytoplasm degrading process, a new hypothesis for cytoplasm preservation in nature is proposed： high temperature, a concomitant of commonly seen wildfires, may preserve cytoplasm in fossil plants. This hypothesis implies that fossilized cytoplasm should be rather common and an appropriate substance for research, unlike previously thought. Research on fossil cytoplasm closely integrates paleobotany with biochemistry, biophysics, as well as fire ecology, and invites inputs from these fields to paleobotany to interpret these provocative findings.  相似文献