混合原油的甾萜类和多环芳烃标志物短期风化规律研究

将胜利和塔西两种原油以不同比例混合后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,探讨和揭示短期风化作用对混合溢油常用的甾萜类和多环芳烃诊断指标的影响。结果表明经过15d的短期风化,在混源比例大于10%时,各系列混合油样的甾萜类生物标志物诊断指标与单一油品的相关诊断比值的差异性和混源油品比例值呈明显正相关。各系列混合油样中的常用萘及烷基萘等指标不适宜作为短期溢油来源鉴别的指标,但可以作为溢油是否发生混合的间接判定指标。根据常用的多环芳烃相关诊断指标,可将各系列油样的短期风化模式依据混源油品中塔西油田原油所占比例大致分为3类(20%~50%、10%和0%)。多环芳烃系列诊断指标的相对标准偏差(RSD%)与混源油品比例有关,混源塔西油样的比例越高,PAHs系列指标的RSD%越大,稳定性越差。     

The origin of nitriles in shale oil

Because nitriles are unlikely to occur naturally in a geological environment but have been reported as being present in some shale oils their origin was investigated. A careful infrared study could find no trace of the nitriles in the shale but it was shown, by infrared and gas chromatography with a nitrogen sensitive detector, that they do occur in some but not all oils. They are formed in the pyrolysis process by the reaction of car?ylic acids and ammonia liberated from minerals such as ammonium feldspars present in the shale. If both species are not present nitriles are not formed in the product oil. Pyrolysis of a brown coal, Loy Yang, in the presence of ammonia produced nitriles but none were generated when a more mature coal (Metropolitan) was similarly treated.     

Reservoir geochemistry of the Tazhong oilfield in the Tarim Basin, China, Part Ⅰ. Geochemical characteristics and genetic classification of crude oils

According to the assemblage characteristics of saturated hydrocarbon biomarkers in crude oils and their geochemical implications, this study has proposed, for the first time, the criteria for the genetic classification of crude oils in the Tazhong area of the Tarim Basin, China. Crude oils from the area studied are classified as three genetic types： type-Ⅰ is characterized by the low contents of C29 norhopane, extremely abundant contents of gammacerane, low contents of rearranged sterane and relatively high contents of regular C28 sterane; the geochemical properties of type-Ⅱ crude oils are opposite to those of type-Ⅰ crude oils; the parameters for type-Ⅲ crude oils are intermediate between type-Ⅰ and type-Ⅱ. Results of oil correlation indicated that type-Ⅰ crude oils were derived from Cambrian-Lower Ordovician hydrocarbon source rocks, type-Ⅱ curde oils originated from Middle-Upper Ordovician hydrocarbon source rocks and type-Ⅲ crude oils are of mixed origin.     

低固相高润滑双聚钻井液体系在地热井施工中的应用

在河南省兰考地区地热井施工中,二开井段深度超过1500 m,采用普通膨润土钻井液体系无法满足地热井施工及对含水层保护的要求,且容易造成卡钻事故。为了解决生产实际问题,研究设计了一种地热井施工用低固相高润滑双聚钻井液体系,通过现场4口井中的应用,钻井过程顺利,有效解决了井眼携砂能力不强、泥岩地层井壁不稳定、砂岩地层失水量大、泥皮厚等问题,4口井均未发生任何井下复杂情况和事故,说明该钻井液体系对兰考地区地层的适应性较好,能够满足该地区钻井工程的需要,对兰考地区地热井施工具有很好的指导意义。     

硫酸盐热化学还原作用的启动机制研究

硫酸盐热化学还原作用(TSR)是导致高含硫化氢天然气生成和聚集、碳酸岩盐储层酸化和溶蚀的重要因素,是地质盆地内烃-水-岩三者之间的复杂反应。本文利用黄金管热模拟实验,对TSR反应的可能启动机制及控制因素进行了研究。通过不同盐溶液与原油的热解实验,证实了硫酸盐的存在是启动TSR反应的必要因素,MgSO4比CaSO4和Na2SO4更容易启动TSR反应,体系中盐度的增加会加速H2S的生成。实验结果表明,不同水介质条件下,TSR反应的程度与溶液的离子强度呈正相关,弱酸性环境并不足以启动TSR反应;原油中不稳定含硫化合物的含量越高越有利于TSR反应的发生,饱和链烷烃比原油中其它组分更容易引发TSR反应,且大分子烷烃比小分子烷烃更容易被硫酸盐氧化。     

准噶尔盆地滴南凸起含油储集岩分子与碳同位素地球化学研究

从滴南凸起10个含油储集岩样品分步提取了自由态油气组分、束缚态油气组分和油气包裹体组分,各组分进一步做色谱、色谱-质谱和正构烷烃单体碳同位素分析。根据生物标志物组成,可将10个含油储集岩样分为两类：第一类包括D2-1和D18-12个侏罗系油砂样,第二类包括其他8个采自侏罗系、二叠系和石炭系含油储集岩样。两类样品生物标志物组成差异主要有：（1）第一类样品各类油气组分三环萜烷含量明显低于第二类样品;（2）第一类样品 C20、C21和 C23三环萜烷含量比较接近,其分布模式为 C20＆lt;C21＆gt;C23,第二类样品这3个化合物含量差异较大,且分布模式为C20＆gt;C21＆gt;C23;（3）第一类样品伽马蜡烷和β-胡萝卜烷相对含量高于第二类样品;（4）第一类样品C27甾烷含量较低而C28甾烷含量较高,第二类样品则相反。可以推断第一类样品自由态组分、束缚态组分和油气包裹体均来源于二叠系烃源岩而第二类样品各类油气组分则来源于石炭系烃源岩。第一类样品油气包裹体成熟度明显高于自由态组分和束缚态组分,表明早期充注原油的成熟度高于晚期充注的原油,总体上各类油气组分成熟度位于生油高峰阶段（Ro 0.8%~1.1%）。第二类样品从自由态组分、束缚态组分至油气包裹体成熟度依次降低,表明早期充注原油的成熟度低于晚期充注的原油,总体上各类油气组分成熟度位于高-过成熟阶段（Ro〉1.25%）。第一类样品各类油气组分正构烷烃单体碳同位素组成相对较轻,第二类样品各类油气组分正构烷烃单体碳同位素组成有一定的差异,组成较轻者与第一类样品各类油气组分接近。     

Geochemical characteristics of oils among real cores in displacement model

Physical simulation experiment on oil displacement is an important approach to understand the mechanism and efficiency of displacement. Physical simulation experiments on water-flooding and chemical flooding in real cores with different lithologies and physical properties, reservoir Rock-Eval, TLC-FID, GC of saturated hydrocarbon fractions and GC-MS of saturated and aromatic hydrocarbon fractions were performed to investigate differences in the geochemistry of residual oils in the cores processed by water-flooding and chemical flooding. After fine sandstone was displaced with the two methods, the preferable replacement efficiency was displayed by the chemical constitutions of residual oils. As to glutenite, water-flooding is less effective, while chemical flooding has excellent performance according to changes in chemical compounds in oils. The results showed that the geochemical characteristics of the reservoir oils and lithology and physical properties of reservoir bed need to be considered in selecting replacement methods. In addition, the geochemical parameters for residual oils slightly changed during water-flooding and chemical flooding, which suggested the water-flooding and chemical flooding could not affect the application of these parameters in geochemistry.     

东海盆地西湖凹陷轻质原油芳烃地球化学特征

采用GC-MS实验技术,对西湖凹陷8口井12个轻质原油样品的芳烃地球化学特征进行了系统研究。平湖斜坡带北部地区NB14-1井、NB14-2井和NB14-3井这3口井的轻质原油与平湖斜坡带中部地区的NB25-1井和NB25-2井、西次凹的HY1-1井以及黄岩构造带的HY2-1井和HY2-2井这5口井的轻质原油芳烃化合物的分布特征和相对含量存在明显差别。轻质原油芳烃馏分中以二环和三环的化合物为主,前者富含菲系列化合物,萘系列和联苯系列化合物含量相对较低,后者则相反,其富含萘系列和联苯系列化合物,菲系列化合物含量相对较低。轻质原油生源和沉积环境的研究表明,原油的母源都主要为陆源高等植物来源,成因环境都为氧化环境,但后者的1,2,5-TMN和1,2,5,6-TeMN相对含量更高,氧芴相对含量和Pr/Ph值更大,反映其母源的陆源高等植物输入程度更大,沉积环境的氧化性更强。烷基萘、烷基菲和烷基二苯并噻吩成熟度指标表明,轻质原油以达到成熟到高熟演化阶段,平湖斜坡带北部地区的NB14-1井、NB14-2井和NB14-3井这3口井的轻质原油热演化程度相对更高。     

Geosteranes: Identification and synthesis of a novel series of 3-substituted steranes

A novel series of 3-alkyl and 3-carboxyalkyl-5β(H)-steranes 7–10 along with a full homologous series of carboxyalkyl-sterane (C₁ to C₆) 4–6 with 3α(H)5α(H) configuration have been identified in marine-evaporitic oils from Fazenda Belém, Potiguar Basin (Brazil) on the basis of mass spectral interpretation. The synthesis of enantiomerically pure 3α-alkyl-5β(H)-cholestane and 3β-alkyl-5α(H)-cholestane standards and their coinjection with petroleum fractions confirmed the structural assignments.     

Olive oil, the Mediterranean and the world

In the last thirty years there has been a growing interest in the use of olive oil in cooking because of greater knowledge of Mediterranean foods and an awareness of the healthy virtues of a Mediterranean diet, and particularly olive oil. In spite of this the consumption of olive oil is negligible outside the Mediterranean region, where most of the world's olive oil is produced and consumed, and which provides nearly all exports and receives a majority of the imports. This seems to be due to the very demanding climatic requirements of the olive tree and the fact that virtually all olive trees are grown in a Mediterranean-type climate. Although the olive tree was taken to areas with a similar climate during the European expansion after 1492, it has never become an important part of the diet in the Americas, in spite of the role of Mediterranean populations settling in the continent. The very high cost of olive oil compared with oilseeds has made its penetration of non-Mediterranean markets very difficult, and indeed the consumption of olive oil has declined in the face of such competition even in some of the Mediterranean countries.