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51.
松辽盆地双城—太平川地区原油地球化学特征及其成熟度差异 总被引:4,自引:0,他引:4
松辽盆地北部双城—太平川地区扶杨油层原油地球化学特征相近,正构烷烃分布完整,呈单峰型,主峰碳主要为C23,部分原油具有轻碳优势,奇偶优势不明显。三环萜烷含量较丰富,部分原油伽马蜡烷、孕甾烷和升孕甾烷含量较高,规则甾烷呈"V"型分布,碳同位素值偏轻,生源构成以低等水生生物和菌藻类为主,兼有高等植物生源输入,母源形成环境为微咸水还原—淡水氧化环境。本区原油的总体特征比较接近,具有相似的生源母质和有机相,但其成熟度存在着一定差异。根据生物标志物参数,原油分为三个组群,即低成熟油、低成熟—中等成熟油和中等成熟油,主要为低成熟—中等成熟原油。认为研究区具有形成低成熟油的有利烃源条件,应该加强对低成熟油的勘探开发。同时加强长春岭背斜带及其周缘构造高部位有利圈闭的勘探与评价。 相似文献
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为研究黔北地区下寒武统牛蹄塘组烃源岩母质来源和沉积环境,开展了生物标志化合物分析,结果表明:④正构烷烃OEP接近1.0,无明显奇偶优势,受轻微生物降解影响,正构烷烃多表现为双峰型(c18/c25),(nC2+nC22)/(nC28+nC29)值为0.54~1.01,显示重烃组分占绝对优势;Pr/Ph值范围在0.51-0.82之间,具有植烷优势。②烃源岩样品组成相对丰度五环三萜烷〉5-g,萜烷〉四环萜烷,三环萜烷中C21、C23、C24呈倒V字形分布,Ts/(Tm+Ts)为0.45-0.50。⑧C27规则甾烷/c∞规则甾烷略小于1或者接近1.芳烃化合物DBT/P为0.05-0.09。根据这些特征并结合干酪根同位素及正构烷烃同位素组成和变化规律,认为该区域下寒武统牛蹄塘组烃源岩形成于浅海还原环境,且有机质主要来源于细菌、藻类等低等水生生物,有机质热演化程度较高。根据常量、微量元素指标并结合有机地化指标刻划出从灯影组到牛蹄塘组和明心寺组沉积时期的水体环境,将牛蹄塘组烃源岩的形成分为3个阶段。第一阶段为早寒武世初始快速海侵阶段,第二阶段为深水还原高有机质产力阶段,第三阶段为海水缓慢变浅高有机质产力阶段,而到了明心寺组沉积时期为浅水氧化非烃源岩阶段。 相似文献
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在对三塘湖盆地中二叠统原油物性、生物标志物特征分析的基础上,开展了油岩生物标志物参数的对比和成藏主控因素的分析。研究认为,中二叠统芦草沟组原油属于自生自储、源内成藏。条湖组原油主要来自芦草沟组烃源岩,属于近源成藏;部分原油(马49井等)来自下二叠统-上石炭统,属于源外成藏。中二叠统的源岩油藏分布主控因素主要体现在源和裂缝两个方面,有效源岩(主要体现在源岩成熟度上)控制了油藏的分布;裂缝(构造裂缝为主)则是控制油藏产能的关键。因此,三塘湖盆地的原油勘探应围绕源和裂缝这两个方面进行,上述认识对油田中二叠统原油的勘探具有积极的指导意义。 相似文献
55.
黔南坳陷下寒武统烃源岩地球化学特征及成因 总被引:2,自引:0,他引:2
为明确黔南坳陷下寒武统烃源岩地球化学特征及成因,采用岩石热解、GC、GC-MS等方法对3个典型剖面样品进行了系统分析。结果表明:黔南坳陷下寒武统黑色岩系为一套区域性海相优质烃源岩,厚约50~150 m;烃源岩TOC值为0.13%~15.40%,平均3.31%(n=169);烃源岩干酪根δ13C值为-35.79‰~-29.88‰,平均-32.85‰(n=35),显微组分主要为腐泥组;烃源岩干酪根海相镜质体反射率值为1.95%~3.96%,其等效镜质体反射率值为2.02%~3.47%;烃源岩饱和烃正构烷烃分布多为单峰形,主峰碳多为C22,C30藿烷和C27规则甾烷含量高,规则甾烷多为C27>C29>C28,Pr/Ph值为0.27~0.62,具较高的伽马蜡烷和硫芴含量,OEP值为0.82~1.11,C31升藿烷22S/(22S+22R)值为0.56~0.63,平均0.59;烃源岩总体具有富集轻稀土元素,Ba、Mo、V、U等元素含量高,具较强Ce负异常、Eu正异常和较高U/Th值等特征。总之,黔南坳陷下寒武统海相烃源岩分布广,厚度较大,有机质丰度高,类型好,热演化程度高,是高古生产力和缺氧环境共同作用的产物,可为黔南坳陷油气生成提供雄厚的成烃物质。 相似文献
56.
MENG Jianghui ZHANG Min ZHAO Hongjing LIU Luofu WANG Zhiyong ZHOU Jieli WANG Ying 《《地质学报》英文版》2012,86(5):1171-1181
Petroleum geologists have debated whether the hydrocarbons from Jurassic coal measures are derived from the coals, carbonaceous mudstones or coal-measure mudstones in the Turpan Basin. Based on the geochemistry analysis of the 20 crude oils and 40 source rocks from the Turpan Basin, some data have been obtained as follows: carbon preference index and methylphenanthrene index of the Jurassic oils are 1.16–1.45 and 0.28–0.80, and the ααα C29 sterane 20S/(20S+20R) and C29 sterane ββ/(ββ+αα) are 0.44–0.51 and 0.4–0.54 respectively, which show the normal maturity of oils; the vitrinite reflectance of the source rocks from the Xishanyao to Badaowan Formations range from 0.47% to 0.97%, which indicate immature to mature thermal evolutionary stage and sufficient conditions for generating mass mature oil. The effect of hydrocarbon expulsion should be considered when studying the source of coal-derived oil by using Biomarkers. Biomarkers in the Jurassic oils from the basin are similar to those in the coals and carbonaceous mudstones, with a strong predominant content of pristane, relatively high ratio of C15/C16 sesquiterpenoids (>1), a relatively high content of low carbon number tricyclic terpanes and C24 tetracyclic terpane, little gammacerane and C29 Ts detected, an absolute predominant content of C29 sterane and a relatively high content of diasterane. However, the opposite characteristics are shown in mudstones, with an approximately equal content of pristane and phytane, relatively low ratio of C15/C16 sesquiterpenoids (<1), a relatively high content of high carbon number tricyclic terpanes and a low content of C24 tetracyclic terpane, peaks of gammacerane and C29 Ts detected obviously and an increasing C27 sterane content. All of these characteristics identify the coals and carbonaceous mudstones as the possible major oil source rocks in this area, and they were formed in the stronger oxidizing environment with shallower water than mudstones. 相似文献
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59.
Sylvie Derenne Franois Robert Audrey Skrzypczak-Bonduelle Didier Gourier Laurent Binet Jean-Noël Rouzaud 《Earth and Planetary Science Letters》2008,272(1-2):476-480
The biological origin of organic matter in the oldest siliceous sediments (cherts) is still debated. To address this issue, the insoluble organic matter (kerogen) was isolated from a chert of the Warrawoona group. The chemical structure of the kerogen was investigated through a combination of analytical techniques including solid-state 13C nuclear magnetic resonance and pyrolysis. Although dominated by aromatic hydrocarbons, the pyrolysate comprises a homologous series of long chain aliphatic hydrocarbons characterized by odd-over-even carbon number predominance. This distribution is only consistent with a biological origin. As kerogen must be contemporaneous of the solidification of the chert, this observation should be regarded as an evidence for the presence of life on Earth, 3.5 By ago. 相似文献
60.
N. Aarab D.M. Pampanin A. Nvdal K.B.
ysd L. Gastaldi R.K. Bechmann 《Marine pollution bulletin》2008,57(6-12):569
Histopathological characteristics of specific organs express condition, and represent time-integrated impacts on the organism stemming from alterations at lower levels of biological organisation. As integrative parameters, histochemical investigations have proved to be sensitive tools to detect effects of chemical compounds.The objective of this study was to determine changes in the tissues of mussels collected at a PAH contaminated site compared to a reference site using histopathological and histochemical parameters: lipofuscin (LF) accumulation in mussel digestive gland, and lysosomal membrane stability (LMS), and using additional information provided by body burden analysis to compare the sensitivity of these parameters.The histochemical measurements for both LF and LMS gave a clear indication of a high level of stress in animals from the PAH contaminated site. This LF accumulation in lysosomes is the result of peroxidation of autophagocytosed proteins associated with protein aggregates and oxidatively damaged organelles. These measurements were able to detect the effects of PAHs, and showed a strong relationship with the body burden results. 相似文献