共查询到20条相似文献，搜索用时 26 毫秒
1.
利用Ｒｏｙｄｅｎ和Ｋｅｅｎ的裂谷伸展模型的大地热流方程，对临清坳陷热演化史进行模拟，结果表明，古热流大于今热流，坳陷是逐渐为冷的，通过建立镜煤反射率Ｒ０与成熟度参数Ｃ的关系式，从而定量地描述有机质成熟度史和沉积物向油气转化的程度，深洼陷中沙一段至沙三段均进入性油门限，沙四段及其以下进入湿气，凝析油及干气阶段，洼陷中浅部沙二段至沙四段位于生油门限之内，故坳陷内可望找到油气。 相似文献
2.
渤海湾盆地文安斜坡高温热流体活动与油气藏形成 总被引：7，自引：1，他引：7
为了研究渤海湾盆地上古生界(C-P)煤系地层油气藏形成和分布的规律，本文通过流体包裹体均一温度、盐度、成份的分析和有机质热演化、粘土矿物转化的研究，对渤海湾盆地文安斜坡苏桥凝析油气田高温热流体的活动和戍藏机理进行了探讨。文安斜坡的流体包裹体分为两期，第一期流体包裹体的盐度为2．2～3．85wt％NaCl，均一温度在91～157℃之间、代表了正常地温梯度和埋藏条件下的古地温；第二期流体包裹体的盐度为4．3～6、85wt％NaCl，均一温度在141～312℃之间．是地下高温热流体活动的结果。高温热流体是由第三纪时期辉绿岩侵入上古生界，引起地层水热对流形成的。高温热流体沿断层、不整合和储层构成的输导系统活动时，加速了粘土矿物的转化，提高了有机质的成熟度，扩大了生油窗的范围。而有机质在生烃过程中释放出的短链羧酸，溶蚀储层中的铝硅酸盐和碳酸盐矿物，形成次生孔隙。统计表明、文安斜坡石炭-二叠系镜质组反射率R。％与第二期流体包裹体的均一温度戍正相关关系，R。％异常高值带对应着储层的异常高孔隙发育带。热流体的活动有利于油气的生成、储层次生孔隙的产生、富烃热流体的运移。并使其在第三纪二次生烃和成藏．热流体活动的地区就是油气聚集的有利地区。 相似文献
3.
沉积盆地热流体活动及其成藏动力学意义 总被引：9，自引：0，他引：9
在分析、总结国内外一些含油气盆地的典型资料的基础上，论述了热流体活动的若干重要表现形式及主要研究方法，强调了热流体活动对有机质热演化和油气生成的强化作用。根据控制热流体活动的主要因素之一--流体活动通道，将沉积盆地内的热流体活动类型划分为岩性型、不整合型、断裂型和复合型四大类。最后，探讨了热流体活动对成藏动力学研究的重要意义，认为其可为有机质演化异常提供新的成因解释途径，扩大油气勘探领域；为油气运移的研究提供线索，优化勘探目标选择；为成岩-孔隙演化的动态研究提供依据，预测深部储层发育层段。 相似文献
4.
沉积盆地热流体活动及其成藏动力学意义 总被引：19，自引：0，他引：19
在分析、总结国内外一些含油气盆地的典型资料的基础上,论述了热流体活动的若干重要表现形式及主要研究方法,强调了热流体活动对有机质热演化和油气生成的强化作用。根据控制热流体活动的主要因素之一---流体活动通道,将沉积盆地内的热流体活动类型划分为岩性型、不整合型、断裂型和复合型四大类。最后,探讨了热流体活动对成藏动力学研究的重要意义,认为其可为有机质演化异常提供新的成因解释途径,扩大油气勘探领域;为油气运移的研究提供线索,优化勘探目标选择;为成岩-孔隙演化的动态研究提供依据,预测深部储层发育层段. 相似文献
5.
从气体地球化学、有机质热变、包裹体均一温度、古地温梯度、成岩矿物、重金属元素和岩浆活动等方面证实了东营凹陷发生了大量的热流体活动.热流体主要沿活动性较强的深大断裂运移至浅部, 并以侧向强迫对流为主, 同时具有多期次活动的特点.热流体通过改变温度场和地温梯度以及带入一些无机物质, 导致水-岩相互作用强度和类型的差异. 相似文献
6.
塔东地区构造热事件及其对原油裂解的影响 总被引：2，自引：0，他引：2
塔东地区目前共有7口探井钻遇油气勘探潜力较大的寒武系-下奥陶统碳酸盐岩地层。主要对这7口井古生界的有机质成熟度资料做了系统分析,发现其中2口井古生界有机质成熟度剖面呈直线型,属于正常的地热演化剖面;另外5口井古生界有机质成熟度存在非常明显的拐点;7口井古生界与中新生界的有机质成熟度之间不连续,即有明显的“断层”,表明塔东隆起区及斜坡区古生界地层的有机质成熟度增加并不是由于沉积埋藏造成的,而是由于深部的异常热事件造成的。从成熟度变化分析,异常热事件在垂向上主要影响下古生界地层,在平面上异常成熟度现象分布在走滑性深大断裂带附近,远离走滑性深大断裂带的井中有机质成熟度表现为正常的热演化剖面,说明在塔东地区异常热事件与深大断裂有关,称之为构造热事件。构造热事件成为塔东隆起或斜坡区在中新生代时古生界原油裂解的主要热动力。7口探井中多期沥青的存在,进一步说明该地区有过后期原油裂解,同一样品中沥青反射率存在明显的差异,反映沥青是在不同阶段形成的。其中1期沥青分布区域没有受到异常热事件影响,沥青只是早期正常埋藏成因;对2期沥青分析说明有1期后期异常热事件,与该区断裂主要活动时期（J3末）是一致的;对3期沥青分析说明存在2期后期异常热事件,与车尔臣断裂带的2期活动（S3-D2、J3末）一致。 相似文献
7.
深部热流体对油气成藏的影响 总被引：21，自引：2，他引：21
深部热流体是一种由多元组分构成的超临界流体 ,其上升活动可使地球内部的物质与能量发生调整或再分配。对油气而言 ,深部热流体携带的高热能可使沉积盆地的古地温升高 ,加快烃源岩的热演化进程 ,增加有效烃源岩的体积 ,促进烃类的生成 ;在上升过程中 ,因其具很强的溶解和扩散能力 ,故可萃取、富集沉积物中的分散有机质 ,同时又对生烃产生显著的加氢作用 ,从而为油气的形成补充物源。此外 ,热流体与围岩储层发生化学反应 ,可改善储层的孔渗条件 ,有利于油气的聚集成藏 ,而且因其具有较高的压力和含水量 ,可抑制烃类的热裂解而有利于油气的保存。 相似文献
8.
地壳中的热流体活动与油气运移 总被引：22，自引：6，他引：22
地壳中的热流体活动实际就是地壳流体作用，是最近十多年来才被认识到并发展起来的前沿科学。地壳流体起着传输能量和搬运物质的作用，是地壳中最活跃的一种营力，直接影响和控制着整个地壳的构造、沉积、成岩和成矿等作用。通过对地壳流体的研究可能产生全新的地质科学理论。油气运移是发生在沉积盆地中的热流活动，它贯穿在整个油气的生成、运移、聚集和散失过程中，直接控制着油气藏的形成并影响着盆地中的构造活动和成岩作用。研究油气运移可以为研究整个地壳流体提供一个窗口和借鉴。不连续的幕式排烃机理可以使人们联想到地壳深部的变质流体也可能呈幕式活动并产生幕式的构造运动。在深部流体活动的作用下有必要对石油的无机成因学说、热降解机理和深盆热水运移等问题重新进行评估。 相似文献
9.
我国中西部盆地深层、超深层油气相态、分布深度和油气贫富差异大,盆地温度场是制约油气成藏及烃源岩成熟演化的关键要素。本文以塔里木盆地和四川盆地寒武系为研究对象,系统解析盆地古、今温度场特征,明确寒武系烃源岩热演化及其差异性,探讨热演化对油气生成及油气相态的控制作用。结果表明,塔里木盆地和四川盆地现今平均热流为(42.5±7.6)和(53.8±7.6) mW/m2,反映了“冷盆”和“温盆”特征。塔里木盆地热流自早寒武世以来呈下降趋势,早二叠世受岩浆活动的影响,出现短暂的峰值。四川盆地寒武纪至早二叠世为稳定低热流,早二叠世末受峨眉山地幔柱热效应的深刻影响,热流快速上升,晚二叠世以来热流下降。由于四川盆地的热状况一直高于塔里木盆地,同时受二叠纪岩浆活动的差异影响,盆地寒武系烃源岩成熟演化、油气生成和相态存在差异。塔里木盆地寒武系烃源岩的热演化具有3种类型：(1)古生代迅速成熟演化定型;(2)早古生代快速演化-后期持续演化型;(3)早古生代和中生代快速演化型。四川盆地寒武系烃源岩的热演化具有3种类型：(1)持续演化型;(2)加里东期热演化停滞-中生代持续演化型;(3)加里东... 相似文献
10.
在烃源岩分布特征及有机质丰度、类型和成熟度分析的基础上,运用含油气盆地数值模拟技术,定量恢复了烃源岩热成熟演化史.研究表明,文昌A凹陷各层系烃源岩分布广,厚度大,有机质丰度高;有机质类型文昌组偏Ⅱ1型,恩平组偏Ⅲ型,二者现今多处于高成熟—过成熟阶段.凹陷内烃源岩成熟时间早（文昌组约45.5 Ma）,成熟度高,以干气生成为主;凹陷边缘烃源岩成熟时间较晚（文昌组约30.0 Ma）,成熟度相对较低,以石油生成为主.凹陷内气藏及凹陷边缘油藏的分布格局受制于有机质类型差异和不同的热演化史.气藏的天然气来自文昌组石油裂解气以及恩平组自身生成的天然气,油藏的石油来自文昌组和恩平组,且油气勘探的方向：凹陷内以天然气为主,边缘以石油为主. 相似文献
11.
12.
南秦岭大型钡成矿带有机地球化学特征与生物标示物研究 总被引：5，自引：0，他引：5
在南秦岭一带的下寒武统硅岩建造中,既存在一大批重晶石矿床,又发育大量毒重石矿床,构成世界上极为罕见的大型钡成矿带。通过对矿床中岩矿石的热解、有机碳分析、氯仿沥青"A"抽提及生物标志化合物等研究,认为含矿地层中有机质的先质母体为菌藻类生物,某些生物标志物指标指示了沉积环境为封闭的缺氧环境。有机质演化受热和生物降解双重作用影响,接近和达到了成熟阶段。在含矿岩石与矿石中,Ba与有机碳含量具有不协调的负相关趋势,有机质成熟度越高,越利于Ba的富集。钡的超常富集,不仅是一个消耗大量有机碳的过程,而且是有机质成熟度不断加深的过程。 相似文献
13.
《Applied Geochemistry》2002,17(11):1467-1494
Samples from the Ocean Drilling Program Leg 169 in Escanaba Trough, Gorda Ridge, NE Pacific Ocean, were analyzed to study maturation by accelerated diagenesis and/or by catagenesis of the sedimentary organic matter to hydrothermal petroleum. At Site 1038 the hydrothermal petroleums have migrated after generation to shallower horizons. The n-alkane maturation was indicated by the strong even C number preference (i.e., CPI <1.0) as in the case of Middle Valley. All samples contained admixed organic matter of terrigenous and marine components as indicated by the distributions of the biomarkers. The biological precursors were catagenetically altered to their equivalent mature compounds. The presence of high molecular weight PAHs in some sediment sections at Site 1038 reflected the high temperature alteration and reworking of organic matter into mature hydrothermal petroleum. At Site 1037, the reference hole in the Escanaba Trough, the n-alkanes with a strong predominance of odd C number homologs reflected immature non-marine lipid components essentially throughout the hole. Maturation of organic matter was only observed below 450 mbsf with n-alkanes showing a CPI <1.0. The strong even C number predominance in those intervals was attributed to initial maturation by high heat flow during the early rifting process. 相似文献
14.
15.
CHEN Xiaohong WANG XiaofengYichang Institute of Geology Mineral Resources CAGS Gangyao Rd. Yichang Hubei 《《地质学报》英文版》1998,72(4):432-440
A great amount of black rock series has been found in the Upper Sinian Members 2 and 4 of the Jinjiadong Formation, middle-upper Liuchapo Formation and the Lower Cambrian Xiaoyanxi Formation in West Hunan, which is associated with periodic sea-level changes. By the studies of relationships between the distribution and development of the biota and the abundance of Au, Ag, U, V, Ni, Mo and Cu in the Upper Sinian and Early Cambrian black rock series in Cili, Dayong, Yuanling, Xupu and Qianyang of West Hunan, central China, it has been revealed that the enrichment of Ag, V, and Mo is related with the development of multi-cell plants and vendotaenides, and that of Cu and Ni is related to flourishing of bacteria and shelly fossils. The black rock series in the study area contains abundant organic matter, among which the siliceous shale contains the highest TOC, amounting to 4.51-13.4%. All the values of the equivalent vitrinite reflectance (medium values) determinated with the IR-spectroscopic method in the a 相似文献
16.
As geochemical appraisals of mineral regions of commercial prospectivity evolve, the organic matter associated with metal rich ores has attracted greater attention. Petroleum basin and modern seafloor hydrothermal vent studies have suggested that organic matter can have a significant influence on the behaviour of mineralising fluids. There have been many isolated reports of certain organic compositional or morphological (e.g. pyrobitumen) features showing an apparent relationships with hydrothermal fluids or minerals, raising expectations that organic based parameters might be useful to mineral exploration. However, the understanding of organic–inorganic relationships in Earth systems is far from complete. For example, the detailed mechanics of the interaction of organics with hydrothermal fluids over geological time remain largely undefined. Organic geochemistry studies have traditionally involved the measurement and interpretation of the hydrocarbon composition of sedimentary rocks. Here we review the types of aliphatic hydrocarbons, aromatic hydrocarbons and metalloporphyrins often detected from organic geochemical investigations in mineral-rich regions. Such molecular data can be particularly diagnostic of biochemical sources and the palaeo-environments at the time mineral associated organic matter was deposited. Sub-surface trends of hydrocarbon alteration may also reflect major biogeochemical processes such as thermal maturity and biodegradation. Organic geochemistry data can also occasionally provide information about the nature (e.g., origin, composition, temperatures) and migration pathways of hydrothermal fluids and can make a contribution to holistic ore genesis models. The well preserved organic matter associated with the economic “Here's Your Chance” Pb–Zn–Ag Mine (Paleoproterozoic Barney Creek Formation, McArthur Basin, Australia) and the transition metal-rich Early Permian Kupferschiefer Formation (Germany–Poland) have attracted significant attention. A more detailed summary of the organic character of these deposits is provided to highlight the contribution organic geochemistry can make to understanding mineralisation processes. Most organic geochemical studies of highly mineralised regions, however, have not adequately addressed the significance of organic matter to mineralisation. A slightly different analytical focus than traditionally used for exploration appraisal of petroleum hydrocarbons may be required to properly evaluate the significance of organic species to the mobilisation, transport and deposition of ore metals. The characterisation and subsequent thermodynamic modeling of organic substances and complexes within metalliferous hydrothermal systems will contribute to a better understanding of the nature and role of organic–inorganic fluids or other affiliated organics in ore systems. 相似文献
17.
酒西坳陷青西凹陷富油的地质-地球化学因素分析 总被引：3，自引：0，他引：3
青西凹陷下白垩统暗色半深湖相-深湖相的泥岩、白云质泥岩和泥质白云岩为研究区主力烃源岩,其沉积时为整体上处于封闭-半封闭强还原-还原环境的断陷湖泊,有利于有机质的保存和转化,且烃源岩厚度占地层比例均大于 5 0%以上,加之有机质类型以混合型为主、有机碳含量普遍大于 1%,为油田形成提供了重要的物质基础。喜山期构造运动形成了许多挤压逆断层、剪切性断层和构造缝,造成地层和构造叠覆,为有机质成熟、运移和聚集提供了动力和空间,从而为该区油藏的形成提供了有利条件. 相似文献
18.
Sedimentary organic matter in hydrothermal systems can be altered by high temperature fluids to generate petroleum. The saturated and aromatic fractions of these hydrothermal oils are compositionally similar to conventional oil with the exception that they often contain higher concentrations of polycyclic aromatic hydrocarbons (PAH) as well as substantial mixtures of coeluting organic compounds that produce dramatically rising signal on the baseline of gas chromatograms termed unresolved complex mixtures (UCMs). Little is known about the compounds that compose UCMs and why or how they form. This is in part due to an inability to discriminate between in situ and migrated components that characterize the petroleum generated in hydrothermal systems. However, UCMs are also a product of the limitations imbedded in analytical separation techniques. With the advent of comprehensive two-dimensional gas chromatography (GC × GC), a revision of what should constitute molecular complexity needs to be considered. We address these problems by comparing the molecular compositions of the maltene fractions of three previously published hydrothermal petroleum samples using time of flight-mass spectrometry (GC × GC–ToF-MS) and 12 hydrothermal petroleum samples in cores from three locales using comprehensive two-dimensional gas chromatography with flame ionization detection (GC × GC–FID). The sediment cores were collected from Middle Valley, located off the axis of the Juan de Fuca Ridge, and the Escanaba Trough, along the Gorda Ridge, both in the NE Pacific Ocean, as well as from the Guaymas Basin in the Gulf of California. We define a UCM in GC × GC data to be a condition in which ⩾25% of the detected peaks within a chromatographic area coelute in either the first or second dimension. In turn, complex (CM) and simple mixtures (SM) are defined as having 5–24% and <5% coelution, respectively. All CM and UCMs were dominated by an array of configurational isomers, which becomes increasingly aromatic with higher molecular weight. We relate this to a multi-molecular complexity metric (MCM) by quantitatively comparing the difference in total peak variance and peak density for a GC × GC chromatogram. MCM values correlate with biomarker thermal maturity ratios for the Escanaba Trough and Guaymas Basin samples indicating that molecular complexity in these hydrothermal environments is in part a function of burial temperatures. Partial Least Squares (PLS) linear regression was applied to the total number of peak retention times as a proxy for the bulk molecular differences between each hydrothermal oil sample. Differences in the sample regressions correlate with the thermal maturity and the degree of PAH alkylation, indicating that this technique can be used to assess the degree of oxidative weathering due to dehydrogenation and hydrocarbon cracking. Subtracted chromatograms were then used to quantitatively track all of the individual molecular changes within the pyrolytic regime at Escanaba Trough. These subtracted chromatograms indicate that high molecular weight PAHs are highly mobile in hydrothermal fluids and may represent a phase partitioning that is occurring at greater depths. This phase condenses just below the seafloor to form an UCM in the near surface sediments. Saturated hydrocarbon biomarkers, such as hopanes, steranes and biphytanes are less mobile and more prone to being cracked and/or aromatized prior to migration toward the ocean floor. Together these techniques suggest that the molecular complexity of hydrothermal petroleum maximizes during the early stages of thermal maturation. The diversity of compounds forming these UCMs then decreases with increasing dehydrogenation, dealkylation and condensation reactions associated with elevated thermal stress and exposure to oxidants within the hydrothermal fluids. 相似文献
19.
济阳坳陷古近系湖相烃源岩的自然演化剖面结果表明,分子标志化合物的演化是一个受沉积环境、矿物组成、有机质赋存状态和温度等多种因素共同影响的复杂过程,其演化具有阶段性,随着埋藏深度增加,大多呈现出“先增大,后减小”的模式。形成于半咸水—微咸水的沙三段下部烃源岩分子标志化合物的演化较为剧烈,温度的影响是主要的,但随着深度的增加,碳酸盐矿物含量逐渐升高对分子标志化合物的演化起到了抑制作用;而形成于咸水—半咸水的沙四段烃源岩分子标志化合物变化平缓,平衡值降低,高盐沉积环境和丰富的碳酸盐矿物在一定程度上延缓了异构化进程。这个结果对于我们正确理解和应用分子成熟度参数具有重要启示,对于咸化湖泊条件下形成的第三系盆地深部地层的勘探具有指导意义。 相似文献
20.
塔中地区奥陶系埋藏热液溶蚀流体活动及其对深部储层的改造作用 总被引：2，自引：0，他引：2
基于矿物流体包裹体均一化温度、热液矿物分布及其地球化学特征等,识别出了塔中地区重点研究井段埋藏热液溶蚀流体化学性质,探讨其在纵横向的分布及流动特征。研究表明,(1)埋藏热液溶蚀流体在塔中地区较为活跃,并对碳酸盐岩储层有着良好的改造效应,油气勘探前景广阔;(2)北东-南西向走滑断裂发育地带有利于埋藏热液溶蚀流体的注入,研究区TZ45以及TZ82-TZ16井区均是埋藏热液溶蚀流体异常活跃地带。同时,研究还认为,早期表生岩溶作用产生的溶洞体系将被后期埋藏压实作用部分破坏,而其残余空间往往是埋藏热液溶蚀流体进入储层的优势通道,继而发生溶蚀改造扩大溶洞空间。因此,在塔里木深部碳酸盐岩储层的勘探过程中,应充分重视挤压背景下张性断裂的发育及其热流体疏导效应,如走滑断裂强烈活动地带;同时应着重注意多期不同性质流体的叠加改造效应,这些区域可作为优选勘探目标。 相似文献