长岭凹陷深层天然气藏中CO_2及CH_4充注次序的流体包裹体证据

对长岭凹陷深层天然气藏储层——营城组火山岩中发育的流体包裹体进行了详细研究,结果表明在火山岩发育的石英、方解石细网脉中均存在较多的碳质流体包裹体,单个包裹体激光拉曼光谱分析结果表明其主要为CO2及CH4两种类型的碳质包裹体。其中方解石细网脉体中发育有原生及次生CH4包裹体,而含CO2包裹体多以原生包裹体产于石英细网脉中。很多含CO2包裹体的石英细脉中发现了含CH4包裹体的方解石脉体的角砾,这就表明石英细脉形成晚于方解石细脉。营城组火山岩储层中CO2及CH4包裹体的产状特征研究表明,松辽盆地深层天然气藏的形成系火山岩成岩后CO2及CH4等气体不同期次充注的结果,CH4气的充注时间早于CO2气,火山岩中发育的原生孔隙及次生裂隙为上述气体的充注和聚集提供了重要通道。     

升平-兴城气田营城组火山岩储层流体包裹体研究

升平-兴城气田营城组火山岩储层经历多次构造活动,具有多期天然气的充注特征。采自该气田20口井45块岩芯样品的流体包裹体系统分析揭示了该区复杂的天然气充注过程。对各期次流体包裹体的均一温度、盐水包裹体的盐度,以及含烃盐水包裹体的荧光强度等测试的综合分析表明,火山岩储层经历了6期热流体活动,前4期分别对应于4期天然气充注过程。结合埋藏史分析可知,4期充注分别发生于泉头组沉积末期-青山口组沉积时期、嫩江组沉积早-中期、嫩江组沉积末期和明水组沉积早期至今。综合考虑生烃层、储层和盖层之间的组合关系,最终确定升平-兴城气田营城组火山岩储层天然气主要的成藏时期为嫩江组沉积早-中期。     

松辽盆地南部幔源CO_2充注成因次生油气藏深、浅层分布差异

在大量总结前人研究成果的基础上得出:松南地区深部层位以富气为特征,烃类气成藏阶段为登二段沉积期及早白垩纪晚期;浅部层位以富油为特征,油气成藏阶段主要集中于明水组沉积末期至古近纪早期;盆地中CO2气主要富集于营城组及泉头组(三、四段),储量丰富且以幔源成因为主,其形成与晚中新世后期火山活动有关;深层与浅层油气成藏时间均早于幔源CO2充注。与深部层位相比,松辽盆地南部浅层具备更完善的幔源CO2充注成因次生油气藏形成条件,可视其为常规油气资源再勘探的有利目标区。     

莺歌海盆地LD10区高含CO2天然气充注期次精细厘定与成藏模式

莺歌海盆地LD10区中深层黄流组?梅山组重力流水道、海底扇储层已被证实具有重大的天然气资源潜力.但是前期测试结果显示气藏中混有高含量CO₂气体.因此,精细厘定天然气充注期次,明确CH₄、CO₂等时空分布规律对规避高CO₂风险至关重要.本研究在对不同产状流体包裹体岩相学特征精细观察的基础上,综合激光拉曼光谱分析和包裹体显微测温技术识别出3幕不同成分天然气充注,时间分别为:4.0~2.9 Ma、2.0~1.2 Ma和0.8~0.3 Ma.其中,第一幕充注以烃类气为主,伴有少量有机CO₂和N₂;第二幕和第三幕充注以大量无机CO₂、烃类气为主,伴有少量N₂.结合天然气及烃源岩地化特征、天然气组分分析及输导体系识别,总结了LD10区的成藏模式,以期为研究区下一步天然气勘探开发和规避高含量CO₂风险提供依据.      

流体包裹体在庆深气田火山岩气藏研究中的应用

松辽盆地北部庆深气田储层火山岩的流体包裹体均一温度为97.1～156.7℃。根据成分的不同可将本区的次生包裹体分为盐水包裹体和含烃盐水包裹体,其中含烃盐水包裹体所占的比例要远小于盐水包裹体。在徐家围子断陷区营城组火山岩储层中检测到6期活动热流体和4期天然气充注,其中含烃盐水包裹体记录了4期天然气向储层的充注过程,其对应的均一温度分别为97.1～114.1℃、121.4～128.3℃、130.5～138.2℃和140.6～156.7℃。结合本区的埋藏史分析,认为4期天然气充注成藏中第三期是形成大规模天然气藏的主期,即泉头组沉积末期至青山口组沉积中晚期。     

库车坳陷东部吐格尔明地区天然气地球化学特征及油气充注史

库车坳陷东部油气地质条件复杂,天然气成因与油气充注时间存在争议,油气充注史不明,制约其油气勘探进程。利用天然气组分、碳同位素组成、流体包裹体岩相学与均一温度等分析测试数据,结合沉积埋藏史及构造演化史,研究了库车坳陷东部吐格尔明地区天然气地球化学特征、天然气成因类型及油气充注时间,分析了油气充注成藏过程。结果表明:吐格尔明地区天然气组分以甲烷为主,甲烷含量为75.56%~90.11%,干燥系数为0.79~0.93;δ¹³C₁和δ¹³C₂值为-35.73‰~-33.80‰和-26.41‰~-25.30‰,天然气成因类型属于成熟阶段的煤成气。吐格尔明地区侏罗系砂岩储层发育两类流体包裹体,分别为黄色液态烃包裹体和蓝白色荧光的气液烃包裹体、灰色的气烃包裹体,表明该区存在两期油气充注,第一期为13~7 Ma的原油充注,第二期为2.6 Ma以来的天然气充注。康村组早中期,吐格尔明地区烃源岩形成的原油充注至宽缓背斜圈闭中保存;库车组晚期,侏罗系克孜勒努尔组与阳霞组发育良好的源储组合,天然气近距离充注成藏。     

跃进地区一间房组流体包裹体特征及油气成藏期次

通过对跃进地区一间房组流体包裹体样品分析研究,据油气、含烃盐水包裹体显微特征及均一温度特征,结合区域地层埋藏史,确定目的层油气成藏时间及期次,为进一步分析成藏过程和指导油气勘探提供依据。研究发现:①跃进地区包裹体类型丰富,有单一液相油包裹体、气液两相油包裹体、含气盐水包裹体、单一盐水包裹体、三相烃类包裹体(气+油+水)、单一纯气相包裹体6种。油包裹体显示黄绿和蓝绿色2种荧光,指示一间房组油气成藏分2个期次;②同生盐水包裹体均一温度主峰为90℃～105℃和110℃～125℃,对应燕山晚期(143～99 Ma)和喜山期(22～2 Ma)2个成藏期,且两期都是油气同时充注,油藏具"早生晚储"特征。     

运用方解石中流体包裹体最小均一温度确定塔河油田奥陶系油气成藏时间:来自激光原位方解石U-Pb年龄的证据

碳酸盐矿物中的同期烃类包裹体共生盐水包裹体均一温度变化范围较大,导致采用流体包裹体均一温度结合储层埋藏史和热演化史确定的油气成藏时间具有多解性.以塔里木盆地塔河油田奥陶系碳酸盐岩油气藏为例,基于方解石脉体中发育的流体包裹体岩相学、荧光分析和显微测温,结合激光原位方解石U-Pb定年结果,提出利用同期烃类包裹体共生盐水包裹体最小均一温度确定油气成藏时间,并确定塔河油田奥陶系碳酸盐岩储层油气充注期次和时间.塔河油田奥陶系储层共存在4期油充注,第1期至第3期油充注时间分别与3期方解石脉体形成时间一致,第4期油充注发生于3期方解石脉形成之后.对发育原生烃类包裹体的方解石脉进行激光原位U-Pb同位素绝对定年,结果指示采用同期油包裹体共生盐水包裹体最小均一温度确定的油气充注时间与方解石脉形成时间一致,说明采用同期盐水包裹体最小均一温度确定的油气充注时间更可靠.运用同期油包裹体共生盐水包裹体最小均一温度得到,塔河地区奥陶系碳酸盐岩油气藏4期油气充注时间分别对应加里东、海西、印支和燕山构造运动时期.      

黄河口凹陷流体包裹体成藏年代和充注期次研究

流体包裹体技术已被证实在含油气盆地的成藏年代和运移期次的研究中是一个有效的手段。关于包裹体在成藏期次方面的研究已有许多,但系统介绍包裹体技术在油气勘探中的应用研究则少见。为推动该方法在油气勘探中的应用,本文从样品制备、分析仪器、流体包裹体镜下特征、均一温度等方面系统介绍了利用流体包裹体确定油气成藏年代与充注期次的方法,以及该方法在黄河口凹陷油气勘查中的应用研究成果:确定了该凹陷普遍发育较低成熟液态烃包裹体、成熟气液态烃包裹体、较高成熟气液态烃包裹体和气烃包裹体3类包裹体,确定了黄河口地区沙河街组油气充注至少有3期:第1期、第2期油气于明化镇组沉积时期开始注入储层(10~5Ma),第3期较高成熟油及伴生气于第四纪开始注入储层(小于3Ma);利用包裹体均一温度还确定了位于黄河口凹陷与渤中凹陷交界的BZ25构造第1期油气来源于渤中凹陷。     

松辽盆地深层火山岩储层的埋藏烃类充注成岩时空演化过程

目前国内对火山岩成岩作用的研究基本停留在定性的静态研究阶段。与盆地埋藏热史烃类充注史构造演化史相应的火山岩储层的成岩孔隙时空动态演化过程方面的研究依然缺乏。各类薄片显微镜下火山岩中原生矿物、次生矿物、孔隙类型等的精细研究与定量统计,利用图像孔喉分析、物性测试、X 射线衍射分析、扫描电镜观察、包裹体荧光、包裹体均一温度与激光拉曼探针成分分析等多种分析测试手段,对松辽盆地下白垩统营城组火山岩的成岩作用与成岩演化过程进行了深入研究,确立了火山岩的成岩油气充注序列,划分了成岩作用阶段;结合松辽盆地埋藏热演化史、烃类充注史、构造演化史,建立了与埋藏热演化史烃类充注史构造演化史地质时代相应的火山岩的成岩孔隙时空动态演化过程与模式,在此基础上讨论了火山岩的成岩作用与成岩演化过程对火山岩储集性能影响的机理。     

The terrestrial fauna of the Late Triassic Pant-y-ffynnon Quarry fissures,South Wales,UK and a new species of Clevosaurus (Lepidosauria: Rhynchocephalia)

Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.     

Définition d'une limite multicritère ; stratigraphie du passage Campanien–Maastrichtien du site géologique de Tercis (Landes,SW France)Definition of a multi-criteria boundary; stratigraphy of the Campanian–Maastrichtian interval of the geological site at Tercis (Landes,SW France)

Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.     

The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts

The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H₂O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H₂O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.     

Quaternary stresses revealed by calcite twinning inversion: insights from observations in the Savonnières underground quarry (eastern France)

Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ₁ roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003).     

HYDROGEOLOGY

正20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level     

METAMORPHIC PETROLOGY

正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7),     

SERIALS

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GEOPHYSICAL EXPLORATION

正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci-     

QUATERNARY GEOLOGY & GEOMORPHOLOGY

正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli-     

PETROLEUM GEOLOGY

正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.)