用储层岩石抽提物的饱和烃色谱指纹识别油气层

利用储层岩石抽提物的饱和烃色 质总离子图的指纹特征判识储层的流体（油、气）类型。油层或油饱和的储层,饱和烃色 质总离子流图的特征是正构烷烃碳数分布宽,碳数分布在C₁₅～C₃₈之间,与原油样品的正构烷烃碳数分布相似;凝析气层的正构烷烃碳数分布略窄一些,碳数分布在C₁₅～C₃₅之间,低碳数（小于C₂₁）的正构烷烃相对于油层富集,高碳数（大于C₂₁）的正构烷烃丰度明显低于油层;干气层的正构烷烃碳数分布最窄,碳数分布在C₁₅～ C₂₈之间,只有低碳数的正构烷烃,高碳数的正构烷烃丰度极低。据此可用来识别油层、凝析气层和干气层,也可用于一些测井资料不全或测井质量差的老井的油气层复查、测井难以识别的火成岩油气层的识别,还可用于地层评价,为油气酸化层位的优选提供科学依据。     

Petrophysical characterisation of tight sandstone gas reservoirs using nuclear magnetic resonance: a case study of the upper Paleozoic strata in the Kangning area,eastern margin of the Ordos Basin,China

Residual and movable porosity are significant parameters for characterising petrophysical properties, especially in tight reservoirs. Eight tight sandstone samples from the upper Paleozoic gas-bearing strata in the Kangning area, from the eastern margin of the Ordos Basin, were analysed using nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), petrography, and porosity and permeability tests. The lithology and pore types were identified and classified using petrography and SEM. The residual and movable porosity were obtained with NMR. In addition, NMR was used to visualise pore structure and pore size distribution. The results suggest that the upper Paleozoic sandstones in the study area mainly comprise feldspathic litharenite and litharenite. The sandstone porosity and permeability are low, with means of 5.9% and 0.549 mD, respectively. Four pore types exist in the tight sandstones: residual primary pores, grain dissolution pores, micropores (clay-dominated) and microfractures. The T₂ spectra under water-saturated conditions correlate with pore size and can be used to distinguish small and large pores based on the transverse relaxation time cutoff value of 10 ms, which corresponds to a pore diameter of 0.232 μm. Small pores account for 72% of the pores in the tight sandstones. The continuous bimodal T₂ spectra suggest good connectivity between small and large pores, despite the low porosity and permeability. In this study, the movable porosity of the major tight sandstone gas reservoirs is higher than the residual porosity, which confirms the effective evaluation of movable porosity to tight sandstone reservoirs, based on NMR experiments.     

Stratigraphic subdivision and correlation of the Carboniferous System in South China

The Carboniferous System of South China is famous for its well-developed rock sequence, variety of depositional types, and abundant fossils. Three established Global Boundary Stratotype Section and Point (GSSP) markers have been identified in several sections in South China. Of these sections, the Pengchong section is the GSSP for the base of the Visean Stage, whereas the Dapoushang and Naqing (Nashui) sections are excellent reference sections for the bases of the Tournaisian and Bashkirian stages, respectively. Other sections have good potential for the four unestablished GSSPs and the Devonian–Carboniferous boundary in South China. The Naqing (Nashui) section is a candidate for the GSSPs of four stages: the Serpukhovian, Moscovian, Kasimovian, and Gzhelian stages. The regional stages of China include the Tangbagouan, Jiusian, Shangsian, Dewuan, Luosuan, Huashibanian, Dalaun, and Xiaodushanian. The history, definitions, reference sections, sedimentary characteristics, biostratigraphy, and correlations of these Chinese regional stages are summarized. A Carboniferous stratigraphic chart of South China is provided, showing the correlation of global chronostratigraphic and biostratigraphic units with those in South China and the lithostratigraphic units of various areas in South China. The chart is presented as a new practical framework for the stratigraphic subdivision and correlation of the Carboniferous System in South China.     

由电子探针分析数据估算角闪石、黑云母中的Fe~（3＋）、Fe~（2＋）

待定矿物化学式中阳离子数法是由电子探针分析值求矿物中Ｆｅ￣（３＋）、Ｆｅ￣（２＋）的新方法。在该方法中，矿物化学式中的阴离子数是唯一已知条件，阳离子数未知，通过本文给出的一系列步骤可以得出实际阳离子数的可能估计。进而求出Ｆｅ＿２Ｏ＿２、ＦｅＯ。该法对Ｆｅ＿２Ｏ＿３、ＦｅＯ的计算结果避免了出现负值，在总体上，该方法的计算结果较其它方法更接近其化学分析值。     

http://dx.doi.org/10.1016/j.gsf.2016.09.005

We propose the nuclear geyser model to elucidate an optimal site to bear the first life.Our model overcomes the difficulties that previously proposed models have encountered.Nuclear geyser is a geyser driven by a natural nuclear reactor,which was likely common in the Hadean Earth,because of a much higher abundance of ~(235)U as nuclear fuel.The nuclear geyser supplies the following:(1)high-density ionizing radiation to promote chemical chain reactions that even tar can be used for intermediate material to restart chemical reactions,(2)a system to maintain the circulation of material and energy,which includes cyclic environmental conditions(warm/cool,dry/wet,etc.)to enable to produce complex organic compounds,(3)a lower temperature than 100℃ as not to break down macromolecular organic compounds,(4)a locally reductive environment depending on rock types exposed along the geyser wall,and(5)a container to confine and accumulate volatile chemicals.These five factors are the necessary conditions that the birth place of life must satisfy.Only the nuclear geyser can meet all five,in contrast to the previously proposed birth sites,such as tidal flat,submarine hydrothermal vent,and outer space.The nuclear reactor and associated geyser,which maintain the circulations of material and energy with its surrounding environment,are regarded as the nuclear geyser system that enables numerous kinds of chemical reactions to synthesize complex organic compounds,and where the most primitive metabolism could be generated.     

浙江新昌地幔岩捕虏体中的硫化物包裹体初步研究

浙江新昌一带晚第三纪碱性玄武岩中地幔岩（二辉橄榄岩）捕虏体内存在大量硫化物熔体包裹体。电子探针分析表明,硫化物相成分主要为镍黄铁矿,次为磁共铁矿。硫化物包裹体的Ｎｉ／Ｆｅ值与寄主地幔岩的橄榄石含量呈正相关。同一包裹体的硫化物相成分不均一,自中心至边缘硫化物的Ｎｉ／Ｆｅ、（Ｆｅ＋Ｎｉ）／Ｓ值和Ｎｉ呈均呈增加趋势。通过与中国汉诺坝、德国ＷｅｓｔＥｉｆｅｌ东欧Ｎｏｇｒａｄ－Ｇｏｍｏｒ地区资料的综合分析,     

Electron Probe Microanalysis of Bromine in Minerals and Glasses with Correction for Spectral Interference from Aluminium,and Comparison with Microbeam Synchrotron X‐Ray Fluorescence Spectrometry

The strong spectral interference between Br‐ and Al‐induced X‐ray lines hampers the utilisation of electron probe microanalysis (EPMA) for measuring Br mass fractions in Al‐bearing minerals and glasses. Through measuring Br‐free Al‐bearing materials, we established an EPMA method to quantify the overlap from AlKα on BrLβ, which can be expressed as a linear function of the Al₂O₃ content. The count rate of the BrLβ peak signal was enhanced by high beam currents and long measurement times. Application of this EPMA method to Al‐ and Br‐bearing materials, such as sodalite and scapolite, and to five experimental glasses yielded Br mass fractions (in the range of 250–4000 μg g^?1) that are consistent with those measured by microbeam synchrotron X‐ray fluorescence (μ‐SXRF) spectrometry. The EPMA method has an estimated detection limit of ~ 100–300 μg g^?1. We propose that this method is useful for measuring Br mass fractions (hundreds to thousands of μg g^?1) in Al‐bearing minerals and glasses, including those produced in Br‐doped experiments. In addition, the natural marialitic scapolite (ON70) from Mpwapwa (Tanzania) containing homogeneously distributed high mass fractions of Br (2058 ± 56 μg g^?1) and Cl (1.98 ± 0.03% m/m) is an ideal reference material for future in situ analyses.     

川西甘孜-理塘金矿带形成条件的矿物电子探针与裂变径迹研究

甘孜-理塘金矿带位于青藏高原东部松潘-甘孜造山带与义敦岛弧造山带的交界部位.通过对嘎拉、错阿、雄龙西、阿加隆洼和曲开隆洼等5个金矿区矿石样品中主要载金矿物黄铁矿和毒砂的电子探针分析,试图探讨区内金矿形成温度、深度和成生环境,并结合矿石锆石裂变径迹定年探讨成矿时代.研究区黄铁矿为S亏损型,普遍含Co和Ni,含量分别为0....     

Influence of environments of coal deposition on phosphorous accumulation in a high latitude, northern Alaska, coal seam

Although phosphorus is a very important biogenic element, its concentration in coal is generally low. Phosphorus (P) concentrations typically range from 0.001% to 0.229% in raw coals of the contiguous 48 states [Glick, D.C., Davis, A., 1984. Variability in the inorganic content of United States coals—a multivariate statistical study of final report, Part 10 (DOE-30013-Flo) to the US Dept. of Energy under contract no. DE-AC22-80PC 30013, 404 pp.]. Some Alaskan coal seams contain horizons that are unusually high in phosphorus. The present paper focuses on a bituminous coal from northern Alaska, where 0.15 m subsections of this coal seam have shown high phosphorous in certain subsections. In order to investigate the lateral extent of such high phosphorous bands in coal, the authors obtained three drill cores up to 3 km apart from the coal seam. A detailed investigation of the cores was undertaken to determine the nature and mode of occurrence of phosphorous minerals. Maceral composition allowed interpretation of environments of coal deposition. Acid-extractable phosphorous analysis of the subsections identified the high phosphorous horizons. Electron microprobe analyses identified the phosphorous mineral as crandallite. Correlation of high phosphorous intervals with corresponding environments of deposition suggests that phosphorous precipitation is promoted by an oxidizing environment with a lowered water table during the peat stage. A study of thin sections from high phosphorous samples showed that crandallite is associated with structured vitrinite and as cell fillings in fusinite. The study confirms the potential for using high phosphorous horizons for the correlation of coal seams, as noted in previous work by the authors (Rao and Walsh, 1997). A high phosphorous horizon is found at 0.45 m above the bottom of the seam in all of the drill holes, indicating a uniformity of the coal forming environment and the availability of crandallite constituent elements over the entire 3 km. The uniformity of high phosphorous concentrations through the top 2 m of the three drill holes also shows a distinct correlation.     

拉萨市夏季大气降尘单颗粒矿物组成及其形貌特征

应用带能谱的电子扫描电镜(SEM-EDX)对拉萨市夏季正常天气下收集的大气自然沉降气溶胶样品进行分析,研究了拉萨市大气降尘矿物组成和各种物相形貌特征信息。拉萨市大气颗粒物含有硅酸盐颗粒、富钙颗粒、富铁颗粒、富碳颗粒(燃煤飞灰颗粒和燃油飞灰颗粒)和植物残体颗粒。根据颗粒物数量统计发现拉萨市大气颗粒物以硅酸盐颗粒为主,富钙颗粒和富铁颗粒次之,需要指出的是以燃油飞灰为主的富碳颗粒已占到一定比重,说明以燃油为主的机动车尾气对拉萨大气污染在加强。研究结果表明,大气降尘矿物成分及其形貌特征可以用作判定污染物来源的重要标志,拉萨大气中颗粒来源的多样性决定了治理措施也应综合进行。