控制内蒙古二连盆地达尔其油田石油富集度的关键因素——不同油源原油的混合作用

在对3套烃源岩的质量和成熟度描述基础上,通过对原油物理性质、族组成和生物标志化合物参数的研究,在达尔其油田内划分出成熟度有明显差异的低熟油和成熟油。油源对比结果认为它们分别由都红木组一段低熟烃源岩和阿尔善组二段成熟烃源岩所生。推测成熟度参数介于低熟和成熟之间的原油为混源油。通过原油混合试验和油砂连续抽提试验证实了混源油的推测。通过油藏剖面中不同性质油层的分布特征研究,结合断层发育史与油气运移关系分析认为不同油源原油的混合是控制该油田石油富集度较高的关键因素。此外,还分析了控制混源的断层组合特征。     

塔河油田原油甾藿烷系列化合物地球化学再认识

生物标志化合物是油气油源、成熟度、运移等领域研究中的一项得力工具。运用生物标志物色谱质谱技术,对比研究了塔河油田各油区原油生物标志化合物中甾、藿烷系列化合物特征。研究表明,塔河油田为一由晚期成熟高、轻微改造的原油与早期成熟度低、遭受较强降解原油混合而成的复合油藏,该油藏各区原油C27—C29甾烷同系物以及C27—C29重排甾烷特征反映出该区不同成熟度原油来自同一母源,原油Ts/(Tm Ts)、重排甾烷/规则甾烷和ββ/(ββ αα)C29比值关系立体图指示出原油的充注方向,印证了“塔河地区的油气主要来自于南部的满加尔坳陷”这一论点。     

刍云深水凹陷高成熟原油芳烃地球化学特征研究

对白云凹陷采集的27个原油样品的芳烃组成进行了系统的研究。其分布特征和相对含量表明,原油母质具明显的陆源高等植物输入特征,沉积环境以氧化环境为主,根据萘系列、菲系列、二苯并噻吩系列化合物的相对含量分布差异,优选有效的烷基萘、烷基菲、烷基二苯并噻吩成熟度指标,综合分析了白云凹陷原油成熟度特征。原油总体属于成熟一高成熟原油,结合生物标志化合物组成可划分为A、B两类,A类原油的成熟度高于B类原油。还选用有效的成熟度参数探讨了白云凹陷油气运移规律,如三甲基萘比值,该参数指示油气运移方向沿白云主洼中心向周围运移,且邻近番禺低隆起,运移方向由西向东,即沿着成熟度由高到低方向运移。     

塔河油田原油甾藿烷系列化合物地球化学再认识

生物标志化合物是油气油源、成熟度、运移等领域研究中的一项得力工具。运用生物标志物色谱质谱技术，对比研究了塔河油田各油区原油生物标志化合物中甾、藿烷系列化合物特征。研究表明，塔河油田为一由晚期成熟高、轻微改造的原油与早期成熟度低、遭受较强降解原油混合而成的复合油藏，该油藏各区原油C27—C29甾烷同系物以及C27—C29重排甾烷特征反映出该区不同成熟度原油来自同一母源，原油Ts/(Tm+Ts)、重排甾烷/规则甾烷和ββ/(ββ+αα) C29比值关系立体图指示出原油的充注方向，印证了“塔河地区的油气主要来自于南部的满加尔坳陷”这一论点。     

东营凹陷生物降解稠油甾烷分子的选择蚀变

为分析生物降解原油中甾烷生物标志物分子发生选择性蚀变的先后顺序及生物降解作用对甾烷分子成熟度参数的影响,在渤海湾盆地东营凹陷广饶潜山油藏选择了发生不同程度生物降解作用的原油,利用色谱质谱(GC-MS)仪对其中甾烷进行了定量测试分析和对比。结果发现在生物降解过程中,不同级别的生物降解作用对甾烷具有不同程度的影响:6级以下的生物降解作用对甾烷的降解能力有限,甾烷及其相关化合物比值没有可以识别的改变;6级以上的严重生物降解作用会对甾烷生物标志物的相关参数产生显著的影响。在严重生物降解原油中(级别≥6):甾烷系列被降解和蚀耗的先后顺序为,ααα20R>αββ20R>αββ20S≥ααα20S,C27>C29>C28,规则甾烷优先于重排甾烷发生降解,C27,C28,C29甾烷优先于C20,C21甾烷发生降解;甾烷生物标志物分子参数C2920S/(20S+20R),C29ββ/(ββ+αα)会发生显著升高,不能真实反映成熟度大小。研究结果为正确评价生物降解原油的成熟度及甾烷生物标志物分子的选择性蚀变提供了新的科学依据。     

车排子凸起轻质油成熟度分析与烃源层再认识

通过对车排子凸起南部轻质油的甲基双金刚烷和甲基菲参数分析,发现其成熟度已达等效镜质组反射率约1.3％～1.6％的高过成熟阶段.结合周边凹陷烃源岩演化特征分析,认为该区轻质油来源于侏罗系烃源岩的可能性较小,来自二叠系高过成熟烃源岩的可能性较大.该区轻质油地球化学特征与二叠系烃源岩差异较大,而与白垩系和古近系烃源岩地球化学特征相似,推断该高过成熟油气中不含生物标志化合物或生物标志化合物含量极低,其现有特征是在运移过程中受成熟度较低而生物标志化合物含量丰富的烃源岩可溶有机质浸染所致.这一认识不但对揭示研究区的油气成藏规律具有重要的理论和实践意义,也将为准噶尔南部深凹区及山前坳陷区轻质原油及天然气来源的重新认识提供合理的参考依据.     

辽河盆地西部凹陷原油的生物标志物类型及其地球化学意义

原油的生物标志物组合特征可提供油气来源、成熟度、次生改造程度等多方面的重要信息,是油气成因分析和油源对比的有效工具.利用原油的生物标志物类型及其组合特征分析地球化学意义,通过生物降解作用的研究和原油生物标志物组合的判断,对稠油的来源进行成因分析,研究认为:辽河盆地不同地区各类生物标志物的组合及正构烷烃和异戊间二烯的分布特征,反映研究区发育母质输入、成熟度和生物降解程度明显不同的两种类型的原油,即富4-甲基甾烷型和富伽马蜡烷型原油,分别来源于沙三段和沙四段源岩.      

非烃地球化学及其应用概述

非烃类生物标志化合物或分子标志化合物是含氧、硫、氮杂原子的有机化合物,每一个饱和烃生物标志化合物可能有多个骨架相似的含氧、硫、氮杂原子的非烃类生物标志化合物,迄今,饱和烃中常见生物标志化合物的非烃类型大都已能被识别.它们被广泛应用于石油成因理论研究和烃类生物标志物的生源研究,近十几年来,它们尚被应用于研究油藏地球化学, 原油的二次运移,古环境、古气候等领域,近年来,非烃中的生物标志化合物还有被用于油 -油对比和用键合在沥青质中生物标志化合物探索严重生物降解油油源的报道,总之,非烃地球化学应用范围不断得到扩展而日益受到重视.     

塔里木盆地北部塔河油田原油分子地球化学特征及成因类型划分

GC、GC-MS、GC-MS-MS分析表明,塔河17区块各油藏原油饱和烃、芳烃生物标志物组成和稳定碳同位素特征具有同源性,即塔河原油来自相同的烃源灶（或烃源层）。然而,对原油物性特征、成熟度特征、生物降解特征及原油馏分碳同位素组成等的深入研究发现,塔河原油属于早、晚两次充注成藏:早期充注为一般成熟型原油,相当于Ro值0.70%0.80%成熟阶段的生排烃产物,遭受生物降解后具有重、稠油特征,主要分布在4、6、7区下奥陶统储层中;晚期成藏原油相当于Ro值0.80%1.00%的高成熟阶段的生烃产物,表现为正常油、甚至轻质油或凝析油,在塔河油田广泛分布,并可以与早期充注油藏原油的生物降解残留成分进行充分混合,呈现复杂的地球化学特征。      

临南地区石油运移方向与成藏期次研究

根据原油及油砂抽提物中含氮化合物分析、原油生物标志成熟度参数及储层流体包裹体烃类成分分析,研究了临南地区石油运移的方向、距离、成藏期次。结果表明临南油田仅有一期油气运聚成藏过程,属中新世末形成的成熟原油,4 甲基甾烷含量较高。曲堤油田存在两期油气运聚成藏过程,早期原油成熟度低,4 甲基甾烷含量低,运移距离较远,成藏后大部分散失 ;晚期充注的原油成熟度较高,4 甲基甾烷含量也较高,并保存至今。     

A geochemical reconstruction of oil generation in the Barrow Sub-basin of Western Australia

A suite of crude oils and petroleum source rock extracts from the Barrow Sub-basin of Western Australia have been analysed for biological marker compounds by capillary GC-MS, and for volatile hydrocarbons by whole oil capillary GC. These analyses were used to calculate values for twenty-three biomarker parameters in order to assess aspects of source type, maturity, migration and biodegradation of the hydrocarbons.The crude oils had a source in the Upper Jurassic Dingo Claystone formation. These hydrocarbons accumulated in the reservoir sands and in some cases were biodegraded. Several accumulation and biodegradation episodes have been recognised while the basin continued to subside, which resulted in a suite of oils showing marked differences in composition.     

用生物标志物定量计算混合原油油源的数学模型

多烃源层叠合盆地混源油油源的定量计算是十分困难的问题.典型原油的人工混合配比实验显示,当两个生物标志物浓度不同的原油相混合时,各类生物标志物的比值参数随端元原油混入量呈非线性变化,以生物标志物比值参数和简单的二元线性关系方程定量计算混源油的混合比例将导致错误的结论.三个或者三个以上原油相混合时,各类生物标志物比值参数的变化更加复杂,各端元原油的贡献更加难以判识.但是,人工混合模拟实验表明混合油中生物标志物绝对含量与端元油的混入量呈线性关系,数学推导证明了这种线性关系,由此推导出相应的数学计算模型,其中:二元混合时比值参数与混入量呈双曲线关系,三元混合呈双曲面关系,四元及其以上的多元混合呈多维曲面,可以矩阵的方式定量计算各端元油的比例.依据这些数学模型,应用生物标志物的绝对含量和(或)生物标志物比值参数均可以定量计算出混源原油中各类原油的贡献比例.数学模型比通常的人工模拟实验方法更加经济、方便、精确和可靠.     

A Mathematical Calculation Model Using Biomarkers to Quantitatively Determine the Relative Source Proportion of Mixed Oils

It is difficult to identify the source（s） of mixed oils from multiple source rocks, and in particular the relative contribution of each source rock. Artificial mixing experiments using typical crude oils and ratios of different biomarkers show that the relative contribution changes are non-linear when two oils with different concentrations of biomarkers mix with each other. This may result in an incorrect conclusion if ratios of biomarkers and a simple binary linear equation are used to calculate the contribution proportion of each end-member to the mixed oil. The changes of biomarker ratios with the mixing proportion of end-member oils in the trinal mixing model are more complex than in the binary mixing model. When four or more oils mix, the contribution proportion of each end-member oil to the mixed oil cannot be calculated using biomarker ratios and a simple formula. Artificial mixing experiments on typical oils reveal that the absolute concentrations of biomarkers in the mixed oil cause a linear change with mixing proportion of each end-member. Mathematical inferences verify such linear changes. Some of the mathematical calculation methods using the absolute concentrations or ratios of biomarkers to quantitatively determine the proportion of each end-member in the mixed oils are deduced from the results of artificial experiments and by theoretical inference. Ratio of two biomarker compounds changes as a hyperbola with the mixing proportion in the binary mixing model, as a hyperboloid in the trinal mixing model, and as a hypersurface when mixing more than three end- members. The mixing proportion of each end-member can be quantitatively determined with these mathematical models, using the absolute concentrations and the ratios of biomarkers. The mathematical calculation model is more economical, convenient, accurate and reliable than conventional artificial mixing methods.     

Demethylated hopanes in crude oils and their applications in petroleum geochemistry

Analyses of some Australian crude oils show that many contain varying concentrations of A/ B-ring demethylated hopanes. These range from C₂₆ to C₃₄ and have been identified from their retention times and mass spectral data as 17α(H)-25-norhopanes. Comparison of hopane and demethylated hopane concentrations and distributions in source-related, biodegraded oils suggests that demethylated hopanes are biotransformation products of the hopanes. Further, it appears that the process occurs at a late stage of biodegradation, after partial degradation of steranes has occurred. Demethylated hopanes are proposed as biomarkers for this stage of severe biodegradation. The presence of these compounds in apparently undegraded crude oils is thought to be due to the presence of biodegraded crude oil residues which have been dissolved by the undegraded crude oil during accumulation in the reservoir sands. The timing of hopane demethylation, relative to the degradation of other compounds, has been assessed and the progressive changes in crude oil composition with increasing extent of biodegradation have been identified. The use of demethylated hopanes as maturity parameters for severely biodegraded crude oils, and the applicability of established biomarker maturity parameters to such oils, are also discussed.     

胡庆油田湖相原油咔唑类化合物的地球化学特征

胡庆油田湖相原油成熟度低，多为低成熟原油，生物降解作用轻微，原油中含有丰富的咔唑类化合物。分析表明，原油成熟度对咔唑类化合物含量及相对组分影响明显，源岩沉积环境对其也有一定的影响，而生物降解作用对咔唑类化合物含量及相对组分影响很小。原油中咔唑类化合物含量、链基咔唑/苯并咔唑及苯并咔唑比值受原油成熟度与沉积环境影响明显，已不适合用来指示油气运移距离，而二甲基咔唑同分异构体比值所受影响小，仍可作为油气运移的有效参数。     

轮南地区奥陶系原油特征及其控制因素

轮南地区油气相态分布非常复杂,奥陶系油气藏平面上具有西油东气的特点。西部轮古西油田、塔河油田和轮南1井区油族成熟度略低且有生物降解痕迹,主要以重油形式分布;东部地区油族成熟度略高,主要以轻质油、凝析油形式存在;中间地段桑塔木断垒带、中部平台区和轮南断垒带发生混合作用形成了中一高蜡油。各地区油气在垂向上变化很大,东部地区奥陶系和石炭系为凝析油气,三叠系又为正常油分布区;西部地区奥陶系为稠油,三叠系为正常油。轮南地区奥陶系在纵向上可能受控于岩溶和储层的发育程度,横向上受控于断裂作用。轮南地区油气成藏时间较早,不同物性的原油都是古油藏多期供油的结果。     

Petroleum system analysis of the Hammerfest Basin (southwestern Barents Sea): Comparison of basin modelling and geochemical data

Exploration in the Hammerfest Basin, southwestern Barents Sea, has proven several petroleum systems and plays with the presence of multiple source rocks of mainly Jurassic and Triassic age. To date several fields and discoveries have been found and are described to mainly contain gaseous hydrocarbons with the presence, in some cases, of an oil leg.Our 3D Hammerfest Basin model shows that the Jurassic Hekkingen Formation and the Triassic Snadd and Kobbe formations reached high maturity levels (gas window) in the western and the northwestern margin. At the same time, this model reproduces the main hydrocarbon accumulations that have been found in the basin. An analysis of the volumetrics and the proportion of oil and gas contributions to each field and discovery, suggests that the gas contribution stems mainly from Triassic source rocks, while the oil phases contain variable proportions from the Jurassic Hekkingen Formation and Triassic source rocks.Gas isotope and maturity related biomarker ratios confirm the maturity trends derived from the basin modelling results. Light hydrocarbons indicate the influence of secondary processes (biodegradation and long distance migration) in the petroleum from the Goliat field and the Tornerose discovery. Age related biomarker ratios such as the ETR (extended tricyclic terpane ratio) and the C₂₈/C₂₉ steranes ratio did not provide a clear separation when evaluating a contribution from Jurassic vs. Triassic source rocks.     

Biodegradation and water washing effect on gasoline range hydrocarbons and quality of crude oils from HJN and MKM fields of upper Assam basin,India

The crude oils from Oligocene and Miocene formation of upper Assam basin have moderate API gravity and significant wax content. Crude oils from HJN and MKM fields of upper Assam basin are being produced from Oligocene and Miocene sands. These oils are somewhat biodegraded in nature as evidenced from their API gravity, density, bulk composition, GC fingerprints and relative concentrations of compounds in the gasoline range. It is observed from whole oil gas chromatographic data that the lighter hydrocarbons are more effected as a result of biodegradation and water washing than the heavier components. In the gasoline range compounds highest degradation of n-alkanes are observed followed by iso- and cyclo- alkanes. The extent of the effect of biodegradation of the gasoline range compounds in crude oil samples cannot be illustrated by the concentrations of the compounds. The concentrations only describe qualitative differences in molecular composition. This difficulty can be overcome by using parameters called degradative loss (%). This parameter shows exactly how much loss or gain has taken place in the gasoline range compounds. Within the gasoline range compounds, n-alkanes, Benzene baring HJN 15 and MKM 14 and Toluene experienced degradative loss indicating effects of both biodegradation and water washing in these oils. Cyclo-alkanes are least effected by biodegradation followed by iso-alkanes in all the oils. The extent of biodegradation and water washing is different for each oils from HJN and MKM fields as indicated by the degradative loss (%) of the compounds in the gasoline range.     

Geochemical characteristics of Ordovician crude oils in the northwest of the Tahe oil field,Tarim basin

Forty-six crude oil samples were selected from the Ordovician in the northwestern part of the Tahe oilfield for detailed molecular geochemical and isotopic analysis, including group compositions, carbonhydrogen isotopes and gas chroma-tograms of saturated hydrocarbons, as well as the characteristics of terpane, sterane and other biomarkers, indicating that crude oils are of the same origin from different districts in the Tahe oilfield and were derived from the same source kitchen (or oil source formation), i.e., mainly stemming from marine hydrocarbons. Detailed studies of oil physical properties of 25-honpane revealed that such oils have heavy or thick oil qualities due to biodegradation. Comprehensive assessment in terms of five maturity parameters shows that the oils from the Ordovician with Ro values varying from 0.80% to 1.59% are widely distributed in the northwest of the Tahe oilfield.     

鄂尔多斯盆地董志——正宁地区原油地球化学特征与成因

鄂尔多斯盆地董志—正宁地区是该盆地中生界油气勘探新区,对该地区原油的地球化学进行研究,了解原油的成因,可以为该地区石油勘探和开发提供科学依据。本研究首次对采集于董志—正宁地区原油和鄂尔多斯盆地烃源岩的烃类生物标志化合物进行了系统的分析,研究了它们的地球化学特征。原油中各类烃类生物标志化合物分布和组成特征指示了原油形成于...