辽河兴隆台构造带原油类型及分布特征

对原油地球化学特征进行对比分析,将辽河西部凹陷兴隆台构造带原油划分成4种类型。各类原油的正构烷烃碳数分布曲线、甾萜类成熟度参数、Pr/Ph等指标有较大差异,并在该区呈规律分布。总体表现为第三系原油由南至北成熟度参数和Pr/Ph值呈降低的趋势,正构烷烃碳数从单峰变化为双峰分布;太古宇潜山内幕及潜山表层原油性质相似,其成熟度明显高于第三系原油。原油分布主要受控于南北洼陷生油层成烃演化差异及与断裂发育时期的相互配置关系。     

多环芳烃油指纹应用于船舶溢油鉴别研究

溢油种类主要包括船舶燃料油和原油,二者性质的差异决定了鉴别方法也相应不同,寻求适合于船舶溢油的鉴别方法具有重要意义。在使用柱色谱层析方法对样品进行分离前处理的基础上,以气相色谱/质谱方法(GC-MS)为主要分析手段,对溢油样品和可疑船舶溢油源样品的多环芳烃油指纹特征进行对比,并在多环芳烃油指纹参数的基础上进一步进行多环芳烃内组成三角图分布特征与聚类分析研究,成功为珠江口水域某船舶溢油事故追踪到肇事溢油源。结果表明:取自丁船的油样和现场溢油样芳烃油指纹特征最为相近,是此次溢油事故的溢油源。受风化作用后的船舶燃料油中饱和烃类化合物数量稀少,且含量极低,不适合用于溢油鉴别,而多环芳烃类化合物较饱和烃类化合物而言具有含量高、种类丰富的特点,是该类溢油鉴别的主要油指纹依据。使用油指纹参数进行可疑溢油源识别时,充分考虑油品中有机分子所受风化影响程度的不同是风化条件下溢油鉴定的关键。因此,多环芳烃油指纹可以有效应用于船舶燃料油溢油的鉴别。     

我国几种常见润滑油的指纹分析

采用气相色谱／质谱方法（GC／MS）对7种常见润滑油中的生物标志化合物（正构烷烃、姥鲛烷、植烷、甾烷、萜烷、多环芳烃）进行定性分析,并基于其生物标志化舍物指纹信息进行了多元统计分析。结果表明,润滑油的气相色谱图中不可分辨的混合物（UCM）具有明显优势;润滑油中含有丰富的甾、萜烷类稠环生物标志化合物,仅含有非常少量的饱和...     

我国几种常见润滑油的指纹分析

采用气相色谱/质谱方法(GC/MS)对7 种常见润滑油中的生物标志化合物(正构烷烃、姥鲛烷、植烷、甾烷、萜烷、多环芳烃)进行定性分析, 并基于其生物标志化合物指纹信息进行了多元统计分析。结果表明, 润滑油的气相色谱图中不可分辨的混合物(UCM)具有明显优势; 润滑油中含有丰富的甾、萜烷类稠环生物标志化合物, 仅含有非常少量的饱和链烷烃(正构烷烃、姥鲛烷、植烷)和多环芳烃类(目标多环芳烃、烷基化多环芳烃、二苯并噻吩同系物)生物标志化合物; 基于甾、萜烷类生物标志化合物指纹信息的主成分分析与聚类分析所得的结果高度一致, 均可用于有一定差异的润滑油的鉴别分析。     

Alteration and multi-stage accumulation of oil and gas in the Ordovician of the Tabei Uplift,Tarim Basin,NW China: Implications for genetic origin of the diverse hydrocarbons

The Ordovician is the most important exploration target in the Tabei Uplift of the Tarim Basin, which contains a range of petroleum types including solid bitumen, heavy oil, light oil, condensate, wet gas and dry gas. The density of the black oils ranges from 0.81 g/cm³ to 1.01 g/cm³ (20 °C) and gas oil ratio (GOR) ranges from 4 m³/m³ to 9300 m³/m³. Oil-source correlations established that most of the oils were derived from the Mid-Upper Ordovician marine shale and carbonate and that the difference in oil properties is mainly attributed to hydrocarbon alteration and multi-stage accumulation. In the Tabei Uplift, there were three main periods of hydrocarbon accumulation in the late Caledonian stage (ca. 450–430 Ma), late Hercynian stage (ca. 293–255 Ma) and the late Himalayan stage (ca. 12–2 Ma). The oil charging events mainly occurred in the late Caledonian and late Hercynian stage, while gas charging occurred in the late Hercynian stage. During the late Caledonian stage, petroleum charged the reservoirs lying east of the uplift. However, due to a crustal uplifting episode in the early Hercynian (ca. 386–372 Ma), most of the hydrocarbons were transformed by processes such as biodegradation, resulting in residual solid bitumen in the fractures of the reservoirs. During the late Hercynian Stage, a major episode of oil charging into Ordovician reservoirs took place. Subsequent crustal uplift and severe alteration by biodegradation in the west-central Basin resulted in heavy oil formation. Since the late Himalayan stage when rapid subsidence of the crust occurred, the oil residing in reservoirs was exposed to high temperature cracking conditions resulting in the production of gas and charged from the southeast further altering the pre-existing oils in the eastern reservoirs. A suite of representative samples of various crude oils including condensates, lights oils and heavy oils have been collected for detailed analysis to investigate the mechanism of formation. Based on the research it was concluded that the diversity of hydrocarbon physical and chemical properties in the Tabei Uplift was mainly attributable to the processes of biodegradation and gas washing. The understanding of the processes is very helpful to predict the spatial distribution of hydrocarbon in the Tabei Uplift and provides a reference case study for other areas.     

气相色谱用于渤海采油平台原油的鉴别

采用气相色谱法对渤海海上6个不同区块、7个平台的8口油井原油中正构烷烃组分及姥鲛烷植烷进行了定性定量分析,通过原始指纹谱图、正构烷烃组分及姥鲛炕植烷浓度分布比较和特征比值比较对原油进行了鉴别.结果表明,不同区块的原油指纹信息不尽相同,即使同一平台不同油井所产的原油指纹也存在一定差异,采用气相色谱法进行分析可对其进行鉴别.原油的风化对特征比值影响较小,可利用其进行风化油样的鉴别.为确保鉴别的准确性,分析过程中必须实施严格质量控制措施.     

Degradation of lubricating oils by marine bacteria observed by quantitative mass spectrometry

Bacterial degradation of the hydrocarbons of lubricating oils was investigated by mass spectrometric analysis which gives both total amount and the composition of hydrocarbon types of residual oil. An unused lubricating oil, which mainly consisted of hydrocarbon types with only a small percentage ofn-alkanes, was degraded by marineBacillus sp. andPseudomonas sp. with 55 % and 25 % decreases in 10 days, respectively. Susceptibility of respective hydrocarbon types to biodegradation was in the following order: alkanes > non-condensed cycloalkanes, mono-aromatics > condensed cycloalkanes. A used lubricating oil of different brand showed a larger decrease than the unused oil. Both species of bacteria degraded large portions of alkane fraction of Arabian light crude oil.     

The petroleum geochemistry of the Termit Basin,Eastern Niger

Sixty crude oils from the Termit Basin (Eastern Niger) were analysed using biomarker distributions and bulk stable carbon isotopic compositions. Comprehensive oil-to-oil correlation indicates that there are two distinct families in the Termit Basin. The majority of the oils are geochemically similar and characterized by low Pr/Ph (pristane to phytane ratios) and high gammacerane/C₃₀ hopane ratios, small amounts of C₂₄ tetracyclic terpanes but abundant C₂₃ tricyclic terpane, and lower δ¹³C values for saturated and aromatic hydrocarbon fractions. All of these geochemical characteristics indicate possible marine sources with saline and reducing depositional environments. In contrast, oils from well DD-1 have different geochemical features. They are characterized by relatively higher Pr/Ph and lower gammacerane/C₃₀ hopane ratios, higher amounts of C₂₄ tetracyclic terpane but a low content of C₂₃ tricyclic terpane, and relatively higher δ¹³C values for saturated and aromatic hydrocarbon fractions. These geochemical signatures indicate possible lacustrine sources deposited under freshwater, suboxic-oxic conditions. This oil family also has a unique biomarker signature in that there are large amounts of C₃₀ 4α-methylsteranes indicating a freshwater lacustrine depositional environment.The maturity of the Termit oils is assessed using a number of maturity indicators based on biomarkers, alkyl naphthalenes, alkyl phenanthrenes and alkyl dibenzothiophenes. All parameters indicate that all of the oils are generated by source rocks within the main phase of the oil generation stage with equivalent vitrinite reflectance of 0.58%–0.87%.     

基于五种油源的中重度风化溢油的常规鉴定指标的应用效果评估

本文利用采集于我国三大油田的五种原油样品开展了长达210天的溢油风化模拟实验,并依据相对偏差和重复性限数学分析法,进行溢油风化过程分析和诊断比值应用效果评估。研究结果表明:经过210天的风化,溢油鉴定诊断比值发生明显改变;其中来源于萜烷、甾烷和多环芳烃的诊断比值变化率要远低于正构烷烃,可用于中长期风化溢油鉴定。此外,研究发现,在这些有效诊断比值中有4个变化率较小,相对偏差低于5%,保持了较好的稳定性,更适合于重度风化溢油鉴定。     

油气差异聚集原理应用效果分析——以黄河口凹陷为例

黄河口凹陷是渤海湾盆地的富烃凹陷之一,近几年勘探发现原油超过2×108m3,天然气超过100×108m3,成果显著。但成功的背后,仍存在众多疑问：地质条件良好的构造上竟然钻了干井,同一个油源的相似构造,钻井结果有的以油层为主,而有的井含气层位多;同一深度段的油层,在不同井中原油密度却存在较大差异。为解决这些疑问,笔者运用差异聚集原理,首先对黄河口凹陷渤中28-2E空圈闭的形成原因进行了分析,建立了本区油气运移的模式。在此模式的指导下对渤中29-4构造开展了评价,准确预测了该构造含油气区域的分布范围,结果证明黄河口凹陷的油气运聚符合差异聚集原理。该原理能够很好的指导本区下一步的勘探,可以取得很好的经济效益。     

Hydrocarbon migration and accumulation of the Suqiao buried-hill zone in Wen'an Slope,Jizhong Subbasin,Bohai Bay Basin,China

The hydrocarbon migration and accumulation of the Suqiao deep buried-hill zone, in the Jizhong Subbasin, the Bohai Bay Basin, eastern China, was investigated from the perspective of paleo-fluid evidence by using fluid inclusions, quantitative fluorescence techniques (QGF), total scanning fluorescence method (TSF) and organic geochemical analysis. Results show that the current condensate oil-gas reservoirs in the study area once were paleo-oil reservoirs. In addition, the reservoirs have experienced at least two stages of hydrocarbon charge from different sources and/or maturities. During the deposition of the Oligocene Dongying Formation (Ed), the deep Ordovician reservoirs were first charged by mature oils sourced from the lacustrine shale source rocks in the fourth member of Shahejie and Kongdian Formations (Es₄+Ek), and then adjusted at the end of Ed period subsequently by virtue of the tectonic movement. Since the deposition of the Neogene Minghuazhen Formation (Nm), the reservoirs were mainly charged by the gas that consisted of moderate to high-maturity condensate and wet gas sourced from the Es₄+Ek lacustrine shale source rocks and mature coal-derived gas sourced from the Carboniferous-Permian (C-P) coal-bearing source rocks. Meanwhile, the early charged oil was subjected to gas flushing and deasphalting by the late intrusion of gas. The widely distributed hydrocarbon inclusions, the higher QGF Index, and FOI (the frequency of oil inclusions) values in both gas-oil and water zone, are indicative of early oil charge. In addition, combined with the homogenization temperatures of the fluid inclusions (<160 °C) and the existence of solid-bitumen bearing inclusions, significant loss of the n-alkanes with low carbon numbers, enrichments of heavier components in crude oils, and the precipitation of asphaltene in the residual pores suggest that gas flushing may have played an important role in the reservoir formation.     

Evaporative weathering of petroleum residues: The age of pelagic tar

The rate of evaporative weathering of a component of crude oil residue is assumed to be proportional to its equilibrium vapor pressure and to the amount remaining in the sample. This model is tested using literature data on normal paraffin profiles of crude oil weathered artificially and gas chromatographic data on crude oil residues weathered on rocky shores. Semiquantitative agreement over the time range from 1 to 400 days is demonstrated. Application of the model to gas chromatograms of pelagic tar lumps collected at Station S near Bermuda in 1972 implies that most of these lumps were formed by fragmentation of much larger and older masses, some within less than one day of the time they were collected. The weathering of pelagic tar thus involves a great deal more physical fragmentation than was previously supposed.     

短期风化对混合溢油组成的影响

对两种原油进行混合配比实验,将混合后油样置于人工气候箱进行风化模拟实验,采用气相色谱质谱联用仪(GC-MS)检测风化样品中的生物标志化合物,短期风化作用对混合溢油的油指纹、生物标志化合物诊断指标等的影响。结果表明,混合溢油的正构烷烃总质量变化与单一原油油品的变化规律相近,即前期风化较快,质量减损较多,而后期风化趋缓,不同混合比例的溢油表现差异不明显。常用于短期风化的诊断比值对各混合油样的风化具有指示意义,但难以定性鉴别油品是否发生混合。重复性限法检验只能判定短期风化过程前后的油样为同一油源,而难以反映油样是否为混合油源的特征,各诊断比值的RSD%值较大可能是混合溢油的一个表现。     

埕北低断阶沙二段原油特性及油源分析

埕北低断阶区沙二段是大港油田近年来重点勘探层系之一,研究目标层段原油特点及油源对比分析对油气勘探具有重要的意义.研究表明,原油物理性质总体表现出高成熟原油特征,具有四低一高的特点,即低密度,低黏度,低胶质＋沥青含量、低含硫量及高含蜡量.原油地球化学性质和原油生物标志特征整体反映出生油母质形成于湖相沉积弱还原环境,具有丰富的藻类贡献,也表现出高成熟油特征.通过原油的物理四性分析和层系间油岩生物标志特征对比研究,分析认为其油气来源为两个方面：主要方面来自歧口凹陷和歧南次凹两大生油凹陷的双向供油,另一方面油气来自沙二段烃源岩的自生自储和沙三段的高成熟烃源岩.     

综合风化条件下渤海原油中PAHs 变化特征研究

以渤海某原油作为研究对象进行50 d综合模拟风化实验,探讨了原油中五类PAHs组分的分布情况及其风化规律.结果表明:经过50 d风化,原油中PAHs的分布发生了较大的改变:萘系列化合物损失最为严重,相对浓度的损失达到56.78%;菲系列所占的比例有所提高,二苯并噻吩、屈、芴系列则保持相对稳定,其分布特征变化规律为进一步筛选溢油来源鉴别新诊断比值参数提供了一定的导向性;经风化检验,现有常用6种PAHs诊断比值在风化50 d后稳定性良好,可用于风化溢油的鉴别.     

Oil-oil and oil-source rock correlations in the Alpine Foreland Basin of Austria: Insights from biomarker and stable carbon isotope studies

The Alpine Foreland Basin is a minor oil and moderate gas province in central Europe. In the Austrian part of the Alpine Foreland Basin, oil and minor thermal gas are thought to be predominantly sourced from Lower Oligocene horizons (Schöneck and Eggerding formations). The source rocks are immature where the oil fields are located and enter the oil window at ca. 4 km depth beneath the Alpine nappes indicating long-distance lateral migration. Most important reservoirs are Upper Cretaceous and Eocene basal sandstones.Stable carbon isotope and biomarker ratios of oils from different reservoirs indicate compositional trends in W-E direction which reflect differences in source, depositional environment (facies), and maturity of potential source rocks. Thermal maturity parameters from oils of different fields are only in the western part consistent with northward displacement of immature oils by subsequently generated oils. In the eastern part of the basin different migration pathways must be assumed. The trend in S/(S + R) isomerisation of ααα-C₂₉ steranes versus the αββ (20R)/ααα (20R) C₂₉ steranes ratio from oil samples can be explained by differences in thermal maturation without involving long-distance migration. The results argue for hydrocarbon migration through highly permeable carrier beds or open faults rather than relatively short migration distances from the source. The lateral distance of oil fields to the position of mature source rocks beneath the Alpine nappes in the south suggests minimum migration distances between less than 20 km and more than 50 km.Biomarker compositions of the oils suggest Oligocene shaly to marly successions (i.e. Schoeneck, Dynow, and Eggerding formations) as potential source rocks, taking into account their immature character. Best matches are obtained between the oils and units a/b (marly shale) and c (black shale) of the “normal” Schöneck Formation, as well as with the so-called “Oberhofen Facies”. Results from open system pyrolysis-gas chromatography of potential source rocks indicate slightly higher sulphur content of the resulting pyrolysate from unit b. The enhanced dibenzothiophene/phenanthrene ratios of oils from the western part of the basin would be consistent with a higher contribution of unit b to hydrocarbon expulsion in this area. Differences in the relative contribution of sedimentary units to oil generation are inherited from thickness variations of respective units in the overthrusted sediments. The observed trend towards lighter δ¹³C values of hydrocarbon fractions from oil fields in a W-E direction are consistent with lower δ¹³C values of organic matter in unit c.     

海洋溢油的风化过程研究

水体中石油的分布与归宿取决于溢油风化.在溢油扩散漂移的同时,发生油类蒸发与溶解过程.石油烃在光能的激发和微量金属离子的催化下会发生氧化反应.石油入海后,在风、浪的作用下很容易发生乳化作用.油膜和分散液滴可附在海洋中悬浮颗粒物上沉淀,溶解的烃类吸附在固体颗粒物上沉淀.石油烃类的生物化学作用为其决定性降解作用.油的风化是许多不同过程的综合过程,它们是同时发生,互相影响的.未来需要在组成、性质和行为相互关系的研究基础上进行.在分子水平上系统研究溢油风化过程对于溢油事故发生后肇事者的确定、危害评价以及生物修复效果评估等具有重要的指导意义.     

渤海石油污染:来自表层沉积物中生物标志物的证据

通过对渤海表层沉积物中饱和烃的分布、来源和分子组成特征的系统分析,探讨了沉积物中生物标志物对石油污染的指示意义。研究表明,沉积物中色谱不可分辨的混合物(UCM)和正构烷烃的分布及组成特征显示出沉积物不同程度地受到了石油烃输入和细菌微生物作用的影响,其中以渤海湾沿岸区域最为明显。渤海湾近岸区和黄河口附近沉积物中正构烷烃平均碳链长度(ACL)低于其他地区,姥鲛烷/植烷(Pr/Ph)也普遍低于1.0,表明可能受到来自于石油平台开采活动、船舶航行、河流输入的石油烃的影响。C₂₇-18α(H)-三降藿烷(Ts)与C₂₇-17α(H)-三降藿烷(Tm)的比值(Ts/Tm)、C₃₁升藿烷22S/(22S+22R)和αααC₂₉甾烷20S/(20S+20R)的比值表明该区域沉积物中有机质成熟度较高,可能受到外来石油烃输入及其衍生物的影响。通过与周边环境中生物标志物分子组成特征的对比发现,沉积物中甾烷和萜类化合物主要来源于石油及其衍生物。将饱和烃各参数进行归一化处理,得到了石油污染的综合替代性指标,并初步圈定了石油污染相对较重的区域。     

Source diagnostic and weathering indicators of oil spills utilizing bicyclic sesquiterpanes

Bicyclic Sesquiterpanes (BSs) are ubiquitous components of crude oils and ancient sediments. BSs in crude oils and diesel oil were identified and characterized, the effects of moderate weathering on BS distributions were discussed, and a methodology using diagnostic indices of BSs was developed for oil correlation and differentiation. The results showed that crude oils and oil products had different abundances and distributions of BSs and, consequently, resulted in different diagnostic ratios. The selected diagnostic ratio indices of BSs, such as BS4/BS5 (ratio of 4,4,8,9,9-pentamethyl-decahydronaphthalene to 8β (H)-drimane), BS6/BS5 (ratio of 4,4,9,9,10-pentamethyl-decahydronaphthalene to 8β (H)-drimane), BS8/BS9 (ratio of the second peak to the third peak of C 16 sequiterpane), and BS8/BS10 (ratio of C 16 sequiterpane to 8β (H)-homodrimane), still maintained better stabilities (%RSD < 5%) after weathering for 30 d. The longer weathering process (150 d) had some effect on such ratios (5% < %RSD < 10%). The facts of the uniqueness, abundance in petroleum, and chemical stability of BSs enable them to be suitable as an effective diagnostic means for identifying spilled oil with moderate weathering, particularly for lighter refined product samples that are difficult to identify by current techniques.     

荧光光谱向量空间距离模式识别法鉴别海面溢油源

采用向量空间距离模式识别法鉴别海面溢油源,研究出4个激发波长和4个发射波长用作数据处理的信息点.对未风化的和风化过的原油,燃料油和润滑油数据进行了研究.并采集了十多条船上的油品验证了方法的可靠性.给出了实验条件下的最小向量空间距离,建立了荧光光谱鉴别海面溢油源的新技术.