河流-三角洲体系微相控烃及机理研究:以珠江口盆地恩平组煤系烃源岩为例

河流-三角洲体系煤系烃源岩是重要的油气来源,传统的研究方法主要为单井点分析,对研究区的勘探程度和资料情况的依赖性大,而且认识滞后于勘探,很难在油气勘探和有利生烃洼陷的预测中发挥作用.对珠江口盆地恩平组煤系烃源岩进行系统研究,揭示煤系烃源岩发育的特征和有利地质条件,并将沉积微相分析与烃源岩的地球化学指标(有机质丰度、生烃...     

Source rocks evaluation, hydrocarbon generation and palynofacies study of late cretaceous succession at 16/G-1 offshore well in Qamar Basin, eastern Yemen

Subsurface Late Cretaceous succession has been recovered from 16/G-1, an offshore exploratory well that located in the Qamar Basin, eastern Republic of Yemen. This paper deals with the study of source rocks, maturation, hydrocarbon evaluation, and palynofacies of the Late Cretaceous Mukalla and Dabut Formations of the Mahra Group. These two formations consist of an intercalation of argillaceous, carbonates, siltstones, sandstones and coal layers. The sedimentary organic matter as amorphous organic matter, phytoclasts and palynomorphs are investigated and identified under transmitted light microscope. Spores, pollen, dinoflagellates, algae, fungi, and acritarchs in addition to foraminiferal lining test have been also identified. The optical and organic geochemical studies were used to evaluate the source rock, maturation and its hydrocarbons potentiality. The thermal alteration index, vitrinite reflectance, rock-eval pyrolysis, and palynofacies were also used. The upward increase in the relative abundance of marine versus terrestrial input reflects a major marine transgression and retregration cycles from Campanian to Maastrichtian stages. The Mukalla and Dabut Formations are late immature to mature stages with kerogen types II and III. The hydrocarbons generation potentiality of two formations is oil and wet gas prone indicators.     

Resources of Kaolinite Rocks in China Coal Measures

The kaolinite rocks are very abundant in China coal mea-sures,most of which are very pure,excellent and in goodquality for industrial use.The geological feature,occurrence,origin and processing techniques are largely different fromthose of the traditional kaolins.The kaolinite rocks in Chinacoal measures are marvelous,but a large-scale kaolinite de-posit is rare in the world.The origin of kaolinite rocks in thecoal measures is under debate for a long time(Liu and Zhang,1 997;Liang,1 995;Boho…     

有机质演化与沉积矿床成因(Ⅱ)--煤成烃类与层控矿床

成煤物质被埋藏以后,在其煤化作用过程中可生成大量气体烃(即煤成气)与少量液体烃(即煤成油)。按照B. JI.科兹洛夫计算值一吨煤产生的甲烷量，褐煤阶段为68M3，到焦煤达270M3，到无烟煤可超过400M3     

华北地台本溪组,太原组火山事件沉积特征及时空分布规律

作者对华北地台24个煤田及煤矿区进行了详细的研究,在本溪组及太原组中共发现6期12次火山事件层。这些火山事件沉积遍及全区,主要为凝灰岩、沉凝灰岩及凝灰质沉积岩,它们在时空分布上有一定规律。火山碎屑可能来自华北地台以北及以南若干不同的火山源,而岩浆可能来自下地壳。      

层序地层格架下烃源岩地球化学研究:以尼日尔Termit盆地为例

如何利用有限的烃源岩样品的实验分析数据和地质资料尽可能地提高烃源岩评价和预测的精度,是当今烃源岩地球化学研究亟需解决的问题.采用层序地层学与油气地球化学相结合的方法,研究了非洲尼日尔Termit盆地基于层序地层格架下,上白垩统Yogou组烃源岩空间分布特征及有机质地球化学性质,初步展示了层序地层格架下烃源岩地球化学研究的方法、应用效果及优势.Termit盆地上白垩统Yogou组海相泥页岩是该盆地主要的烃源层,自下而上可划分为YSQ1、YSQ2和YSQ3共3个三级层序.根据层序/体系域发育特征、岩性录井和测井曲线响应特征,识别出外陆棚、内陆棚、三角洲、滨岸相泥岩及煤/炭质泥岩共5种不同沉积类型的烃源岩,不同层序与体系域具有不同的烃源岩纵向叠置关系和横向分布特征.不同类型的烃源岩有机质具有明显不同的地球化学性质:外陆棚和内陆棚泥岩有机质丰度中等-好,有机质生物来源中,低等水生生物贡献高,沉积于偏还原的沉积环境.滨岸和三角洲相泥岩有机质丰度高,具有低等水生生物和高等植物来源的双重贡献,沉积于偏氧化的沉积环境.三级层序或其体系域控制下的沉积相分布和演化导致不同类型烃源岩的发育和横向分布特征,同一沉积相类型的烃源岩具有相似的地球化学性质.与传统的以组、段为单元的烃源岩地球化学研究相比,层序地层格架下的烃源岩评价可以刻画不同层序、不同体系域和沉积相带烃源岩有机质地球化学性质的差异,提高资源评价和油-源对比的精度.      

早期煤化作用机制与有机质早期成烃演化

近年来，未熟和低熟油气田的发现、生物气藏的勘探和开发，极大地促进了对有机质早期转变的研究；而有机质早期转变机制的正确认识对于煤和干酪根中显微组分的成因、后期热演化都有着重要的影响。对早期煤化作用机制和有机质早期成烃作用的研究现状、进展及存在的问题进行了综述。     

西湖凹陷西斜坡平湖组烃源岩沉积成因分析

西湖凹陷西斜坡是东海盆地当前油气勘探的现实选择和主要领域，但以往研究在烃源岩形成条件和分布规律等基本地质问题方面尚未形成共识.在沉积学、煤岩学和有机地球化学等理论指导下，利用钻井、烃源岩有机地球化学及古生物等资料，对西湖凹陷西斜坡钻井揭示的平湖组烃源岩成因类型和形成条件进行了全面系统分析，建立了与沉积环境相对应的有机相划分方法，并总结了平面分布规律.研究表明，烃源岩主要为煤系烃源岩，次要为海相泥岩；西斜坡中北部以受潮汐影响的三角洲-障壁海岸沉积体系为主，西斜坡中南部为潮坪-半封闭海湾体系；沉积环境差异决定了烃源岩类型的不同，潮坪-泻湖比三角洲具有更高的煤系发育程度和生烃能力.研究结果对西斜坡烃源岩评价和储层预测及勘探部署有较大指导作用.      

Transformation of the pore space during the simulation of the generation of hydrocarbon fluids in the Domanik horizon of the South-Tatar crest as an example

The main purpose of this paper is to study the factors that control changes in rock structure during catagenetic transformation of organic matter. Hydrocarbon generation and primary migration can be controlled by numerous parameters; the most important are temperature, pressure, hydrocarbon composition, and organic matter type and content. The influences of most of these parameters have been studied and experimentally demonstrated. However, there are a few works that are dedicated to the investigation of the texture features of rocks, as well as the quantitative content of the organic matter on the pore space transformation of rocks. Therefore, these parameters are the most important when studying the primary migration processes. It was found experimentally that the rock pore space after each stage of heating is transformed, forming new pore spaces and channels that connect the primary pores. A sample with a relatively low content of organic matter has been found to undergo fewer changes in pore-space morphology in comparison to rock that is saturated in organic content. It has been found that that the change of pore-space morphology depends on the original structure of the rocks. Most of the structural changes were observed during rock heating within 260–430°C; the most intense formation of hydrocarbons was revealed within this interval.     

Distribution and formation conditions of noble metal mineralization in coal-bearing basins

Original data and a survey of the literature indicate that Au and Au-PGE mineralization are abundant in coal measures. Anomalous contents of noble metals have been established in basins with various types of basement, composed of granite, volcanic rocks, schist, and limestone. These basins are located in Au-and PGE-bearing ore districts, as well as at a considerable distance from known ore deposits and occurrences. Ore formation in coal-bearing basins may occur during sedimentation, peat accumulation, and diagenesis of organic matter or may be epigenetic. Noble metals are supplied to sedimentary basins as minerals that are transported by water and air and as ion species migrating along with surface and subsurface in-and exfiltration solutions of various chemical and genetic types. Ore mineralization concentrates in coal seams and host sedimentary beds of various grain size, including conglomerate, sand, and clay, as well as in zones of hydrothermal alteration superimposed on basement rocks and the sedimentary cover. The mode of occurrence of noble metals in coal basins is diverse as well (noble metal minerals, isomorphic admixtures in sulfides, and organic compounds). The data presented allow coal-bearing basins to be regarded as promising for economic noble metal mineralization fit for recovery as by-products in the course of coal mining.     

泌阳凹陷核桃园组湖相碳酸盐岩系孢粉相及烃源岩评价

孢粉相是反映一定沉积物以及成岩作用环境的显微沉积有机质组合。对我国河南泌阳凹陷下第三系核桃园组核三上段至核二段湖相碳酸盐岩系孢粉相进行了详细研究。基于有机质组分的鉴定和统计将碳酸盐岩系划分为五个孢粉相带;并利用孢粉相结合有机质成熟度地化指标,对其生油潜能进行了评价。     

用显微组分的双重属性研究沉积有机相

沉积有机相是近年来国内、外广泛运用于油、气勘探的一种有效的研究方法。沉积有机相的区分主要依据源岩有机质的地球化学性质和光性特征。实际上,源岩显微组分的特征、类型、数量和产状是源岩有机质的岩石学和地球化学特征的双重反映,并和沉积环境密切相关。因此,利用源岩显微组分的属性可以简便快速地确定沉积有机相,并可更好地反映盆地内油气资源的分布状况。根据该方法对准噶尔盆地和吐鲁番-哈密盆地侏罗纪煤系的沉积有机相进行研究,圈定了有利的煤成油相带。     

辽西牛营子凹陷北票组烃源岩生物标志化合物特征——以辽凌地1井为例

采用气相色谱、气相色谱-质谱技术,研究了辽西牛营子凹陷辽凌地1井1527.91~1722.78 m(未见底)北票组烃源岩的生物标志化合物特征,剖析其沉积环境、有机质生源、有机质热演化程度等方面的信息. 牛营子凹陷北票组烃源岩样品的正构烷烃相关参数间接表征烃源岩成熟度较低,多为未成熟-低成熟阶段;有机质输入以陆源输入为主,有部分低等生物输入; Pr/Ph值主要介于0.94~5.01之间,平均为3.40,具有典型煤系地层有机质特征,形成于偏氧化性环境; C₂₄TeT/C₂₆TT-(C₂₀ +C₂₁)TT/(C₂₃+C₂₄)TT值整体偏高,指示一种高等植物来源; C₂₄-四环二萜/C₂₆三环萜烷比值分布于1.15~5.28,平均值为2.76,表明其陆源高等植物贡献较为充足;伽马蜡烷指数分布在0~0.04,平均值为0.02,反映当时的沉积环境为淡水环境;在m/z217质量色谱图中样品甾烷呈现C₂₉甾烷占优势的反"L"型,表示为高等植物输入占绝对优势. 综合研究认为牛营子凹陷北票组烃源岩形成于淡水的偏氧化性环境,具有典型煤系地层有机质特征,有机质来源为陆源高等植物贡献,具有油气勘探前景.     

祁连山木里地区侏罗系窑街组烃源岩生烃潜力评价

祁连山木里坳陷侏罗系窑街组煤系泥岩和煤有机质丰度、有机质类型和有机质成熟度分析结果表明, 窑街组煤系泥岩为好的烃源岩, 有机质类型为Ⅱ₁型, 处于成熟阶段, 以生油为主, 生气为辅; 煤为差等烃源岩, 有机质类型为Ⅲ型, 处于成熟阶段, 富氢基质镜质体含量高, 具有一定的生烃潜力。综合其它层位烃源岩分析结果, 认为窑街组煤系泥岩和晚三叠世尕勒得寺组湖相泥岩为祁连山木里地区天然气水合物的主要气源岩。      

黄河北地区晚古生代岩相古地理与煤系烃源岩发育

黄河北地区广泛发育各种沉积体系,通过对其沉积特征及沉积模式的分析发现黄河北地区晚古生代石炭-二叠纪海相、陆相和过渡相环境均有发育。该地区存在的主要沉积体系类型是潮坪沉积体系、障壁-潟湖沉积体系、河控浅水三角洲沉积体系和河流-湖泊沉积体系。研究发现:本区石炭-二叠系储层烃源岩发育有意义的三个沉积演化阶段分别是本溪期、太原期、山西期;黄河北地区属鲁西地区一部分,晚古生代石炭-二叠系含煤地层主要发育砂岩、泥质岩、碳酸盐岩、岩浆岩和可燃性有机岩(煤),是重要的烃源岩;黄河北煤田含煤地层含煤14层,其中1~5层煤赋存于山西组,6~14层煤赋存于太原组,就可采煤层的层数来说,存在“东多西少”的特点;在含煤地层剖面上的分布特点是“上薄下厚”,主要富煤带则主要分布在东部地区;泥页岩主要发育在石炭-二叠系太原组和山西组,泥页岩层厚度在横向上有一定的规律性,由北向南泥页岩层厚度有逐渐减小的趋势,南部济西矿区和长清矿区,西北部伦镇矿区、李屯矿区厚度发育较好,多在90m以上。     

国外孢粉学研究动态──孢粉相分析

全文介绍了国外在近几十年中对抱粉相研究的发起、深入和逐步趋向完善。通过研究薄片中各抱粉有机物质的百分含量、保存状况以及一些具特殊指相意义的孢粉类别,利用图示法将它们表示出来,最终与几种海相页岩沉积相分别对应起来。这方面的工作无疑会推动地质学领域内其它学科的发展。     

Impact of Montmorillonite and Calcite on Release and Adsorption of Cyanobacterial Fatty Acids at Ambient Temperature

Minerals might act as important sorbents of sedimentary organic matter and reduce biodegradation, which favors the formation of hydrocarbon source rocks in the earth's history. Since most organic matter is degraded during the sinking process, at ambient temperature, it is important to investigate the adsorption capacity of different minerals during this process, to assess the organic loss from primary productivity to sedimentary organic matter. In this study, montmorillonite and calcite have been selected to study the impact of different minerals on the release, adsorption, and deposition of cyanobacterial (Synechococcus elonpata) fatty acids (FAs) at ambient temperature. Gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS) have been utilized to detect the variation in fatty acids. Primary results suggest that minerals have a different impact on dissolved organic matter. Montmorillonite can specifically enhance the release of fatty acids from cyanobacterial cells by lowering the pH values of the solution. The adsorption of the dissolved organic matter by montmorillonite will also be enhanced under a lower pH value. Conjunction of fatty acids with montmorillonite to form a complex will favor the sinking and preservation of these organics. Selective adsorption is observed among fatty acids with different carbon numbers. In contrast, calcite does not show any impact on the release and adsorption of organic matter even though it is reportedly capable of acting as a catalyst during the transformation of organic matter at high temperature. The primary data bridge a link between primary productivity and sedimentary organic matter, suggesting the relative importance of claystones in the formation of hydrocarbon source rocks in the earth's history.     

生物标志物地球化学的新进展

生物标志物地球化学是７０年代以来迅速发展起来的分支学科。它通过分析生物标志物的化学组成及构型转化来研究沉积有机质的演化及沉积矿产特别是石油的成因。本文以我国东部油田下第三系生油岩及原油中生物标志物的分布为例，简介了它们为油气勘探提供有关有机质来源、沉积环境、成熟度、油气运移及生物降解等多方面信息的重要作用及其新的进展。     

Hydrocarbon of source rocks evaluation study of Lokichar Basin, Northwestern Kenya

The hydrocarbon potential of the sub-surface Tertiary sedimentary rock sequences of the Lokichar basin system (NW-Kenya) has been interpreted using some selective geochemical analysis of rock samples in Loperot-1 Well (denoted as LT-1 Well) for their total organic carbon (TOC) which forms the premise of this study. Understanding the sub-surface structures and depositional environments conducive for hydrocarbon generation and trapping is essential as it forms the basis for exploration. The organic matter richness and degree of thermal alteration and/or maturation are factors useful in evaluating the potential source rocks. Rock-Eval pyrolysis has been employed on selected rock samples with high TOC for quantification of data and this would help in precise identification of phases of hydrocarbon generation.     

准噶尔盆地侏罗纪含煤地层沉积有机相研究

准噶尔盆地侏罗纪煤系是一套良好的生油源岩，其生油潜力取决于沉积有机相。笔者依据有机岩石学研究方法，利用显微组分的多种特性，将侏罗纪沉积期划分成高位沼泽、森林沼泽、流水沼泽和开阔水体４种沉积有机相类型，其中森林沼泽有机相和流水沼泽有机相是主要的生烃有机相，森林沼泽有机相是煤成气的主要源区，流水沼泽有机相则是煤成油的主要源区。