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1.
有机地球化学参数在层序划分对比中的应用——以冀中拗陷束鹿凹陷沙三下亚段为例 总被引：1，自引：0，他引：1
深水细粒沉积层系的层序地层单元细分和对比,是建立合理的层序地层格架的关键,也是进行深水区岩性油气藏勘探开发的一项重要基础研究工作。但往往由于细粒沉积层系层序地层单元划分标志不明显,其划分对比较为困难,这也是层序地层学研究的难点。依据高分辨率层序地层学原理,从沉积层序的成因及其表现入手,应用表征沉积环境或沉积物特征的有机地球化学参数在纵向上的周期性变化规律,对渤海湾盆地冀中坳陷束鹿凹陷沙三段下亚段半深湖—深湖相泥灰岩沉积进行了层序地层单元划分和对比,较好地识别出了4级旋回与5级旋回,为建立高分辨率层序地层格架奠定了基础。 相似文献
2.
伦坡拉盆地丁青湖组油页岩呈北西-南东向断续分布,长约50 km,油页岩有18~22层,薄者0.10 m,厚者8.81 m,一般厚0.70~2.00 m。工业分析数据表明,油页岩属于高灰分、中低含油率、低发热量型。油页岩有机碳质量分数为2.40%~20.23%,平均值7.38%,丰度较高。干酪根镜检显示油页岩有机质类型为腐泥型（Ⅰ型）,镜质体反射率（Ro）值为0.43%~0.71%,平均值为0.52%,说明油页岩有机质处于未成熟-低成熟阶段。油页岩样品检测出丰富的正构烷烃、类异戊二烯烷烃、萜烷化合物和甾烷化合物。饱和烃色谱/质谱特征表明伦坡拉油页岩有机母质来源以水生浮游植物为主。通过生物标志物特征及野外地质观察,揭示了油页岩形成于一定盐度的缺氧还原半深湖-深湖环境。湖盆内各种水生浮游植物、藻类等为油页岩的形成提供了主要的有机母质来源,稳定的构造条件和缺氧的环境有利于有机质的堆积和保存。 相似文献
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4.
赛里木湖沉积物有机质变化特征及其环境信息 总被引：3，自引：0，他引：3
在分析赛里木湖湖泊沉积物中氮含量(TN)、有机碳含量(TOC)及其碳同位素(δ~(13)C_(org))以及色素等指标的变化特征的基础上,结合沉积物中有机指标的环境意义的探讨,揭示了新疆赛里木湖湖泊沉积物中有机质所蕴含的环境信息.赛里木湖沉积物中总有机碳含量、总氮含量的变化反映了流域初级生产力的变化,沉积物色素变化是有机质保存条件的指标,间接指示了湖泊-流域水热配置环境.有机碳同位素(δ~(13)C_(org))反映了湖泊内外源的混合信息.结合有序样品聚类分析方法,可以将赛里木湖近代环境划分为四大发展阶段:1、各有机指标相对稳定;2、各有机指标明显波动;3、各有机指标显著增加;4、各有机指标快速增加. 相似文献
5.
《International Geology Review》2012,54(5):889-894
This review and discussion is an addition to the series of discussions of the book by Eames, et al., which have been presented by paleontologists dealing with mid-Tertiary biostratigraphy around the world. The effect of the series of published reviews and comments has been to further stimulate a most healthy discussion of the problems relating to the correlation of Oligocene and lower Miocene beds. In discussing the first portion of the book, which deals with mid-Tertiary correlations, V.A. Krasheninnikov disagrees with the designation of the Lattorfian stage of the Oligocene in the Middle East, pointing out that the limestones referred to the Lattorfian stage give way along strikes to argillaceous limestones and marls with fauna known to be upper Eocene by analogy with beds in the U.S.S.R. The Lattorfian stage of the Middle East is thus considered to be a shallowwater facies of the upper Eocene. It is also considered that upper Oligocene deposits of Syria and the U.S.S.R. (Ciscarpathia) have been wrongly transferred by Eames, et al., to the Aquitanian stage of the Miocene. However, since many foraminifer species and genera mentioned in European and Soviet works have been described on the basis of finds in the American “Oligocene,” it will now be necessary to check the accuracy of the species determination in Europe in the light of revisions of mid-Tertiary stratigraphy in the Caribbean basin. The Aquitanian stage as considered by Eames et al. includes not only undoubted Aquitanian deposits, but also the Burdigalian stage. The Burdigalian of the authors corresponds to the Helvetian of Italian geologists and the lower Tortonian of Central Europe and the U.S.S. R. Because of this a later emergence of the genera Orbulina and Biorbulina is assumed in the Miocene of Central Europe, while in reality the emergence of these genera and their accompanying foraminifers was simultaneous both in the territory of the present Mediterranean and that of Europe. Erroneous contentions by the authors are due largely to too narrow a consideration of the stratotypes without determining the whole series of foraminfer complexes from the diverse facies within the limits of the stratigraphic subdivisions. The second part of the book deals with the mid-Tertiary Globigerinaceae and includes the tracing of several morphogenetic lineages. The information presented is considered unconvincing in many cases and is inadequate to form a basis for the conclusions reached. The book under review is assured of its place in geological literature and makes fascinating reading because of the wealth of factual material it contains and the authors' formulation of fundamental theoretical problems of Oligocene and lower Miocene stratigraphy.—H.C. Kent 相似文献
6.
B. I. Pavlyutkin I. Yu. Chekryzhov T. I. Petrenko 《Russian Journal of Pacific Geology》2011,5(1):47-63
New data were obtained on the Voznovo Formation, one of the key Tertiary stratigraphic units in East Sikhote-Alin. The analysis
of macro- and microflora in this unit showed that the decision to assign it to the Miocene (Resolutions…, 1994) was invalid. The early Oligocene age of the formation is justified. It is shown that the sediments constituting the
formation were deposited in a barrier lake. The analysis of the Voznovo taphoflora reveals its mountainous ecotype, which
indicates the ancient age of the Sikhote-Alin mountainous system. The Voznovo Formation is correlated with other coeval stratigraphic
units of the region. 相似文献
7.
Alain Thomas 《Engineering Geology》1971,5(4):313-329
Can we justifiably use a special drying process for measuring water content and dry density on marls containing gypsum so as to avoid errors due to the thermal dehydration of gypsum? In order to give an answer to this question, the author studied the variation of the systematic errors in the measures with measurable parameters such as temperature, length of drying time, gypsum content and water content. He also examined the incertitude due to the non-numerical parameters of dispersion, such as the nature of the tested marls and the size of the gypsum inclusions.
These investigations allowed the author, within the numerical parameters studied, to determine the regions where the precision of the corrections possible justifies the use of special methods of testing. He also shows that the usual way of desiccation below 55°C, is reliable only within a very limited range of water content. 相似文献
8.
山东惠民凹陷中央隆起带古近系沙河街组层序地层特征及控制因素研究 总被引：2，自引：0，他引：2
结合山东惠民凹陷中央隆起带古近系层序地层学研究,依据层序中湖平面变化特点和相应的沉积物特征,提出了构造运动和气候是本区层序地层发育的主要控制因素。中央隆起带古近系沙河街组二、三、四亚段可划分为 3种层序类型,即断陷初期型、强断陷期型和断陷后期型层序。由于构造运动导致湖岸线向盆地方向退缩,产生下降体系域,本次研究采用了体系域的四分法,即一个完整层序由低位、湖侵、高位和下降四个体系域组成,并且层序界面位于湖平面最大下降的位置,介于下降域和低位域之间。断陷初期红色地层层序,受气候因素控制明显,既不同于冲积地层层序,也不同于正常湖相地层层序,在层序演化上有其独特的特点。受构造作用和沉积物补给条件的影响,研究区发育三种沉积密集段,不同类型的沉积密集段在层序中所处位置不同,控制着不同的烃源岩厚度和油气资源储量。 相似文献
9.
柴达木盆地西部地区古近系和新近系湖相碳酸盐岩主要分布于下干柴沟组上段到油砂山组,其中,下干柴沟组上段和上干柴沟组的碳酸盐岩更发育。碳酸盐岩主要岩石类型有泥晶灰岩、藻灰岩和颗粒灰岩等三大类,此外,还普遍发育由石灰质、白云质和陆源碎屑等3种组分构成的混积岩。碳酸盐岩沉积相可划分为滨湖灰泥坪、滨湖藻坪、浅湖颗粒滩、浅湖藻丘以及半深湖泥灰岩相。滨湖灰泥坪的主要岩石类型有泥晶灰岩、含陆屑泥晶灰岩、陆屑泥晶灰岩以及陆屑泥灰岩等;滨湖藻坪为藻泥晶灰岩、藻纹层灰岩、含陆屑藻泥晶灰岩;浅湖颗粒滩有亮晶或泥微晶的鲕粒灰岩、生屑灰岩和内碎屑灰岩,其次为含陆屑颗粒灰岩;浅湖藻丘为藻叠层灰岩、藻团块灰岩、藻泥晶灰岩和含陆屑藻泥晶灰岩;而半深湖泥灰岩相的主要岩石类型为泥晶灰岩、泥灰岩以及含少量陆屑泥和粉砂的泥晶灰岩或泥灰岩。碳酸盐岩沉积相表现出很强的由西南向东北的迁移性。 相似文献
10.
MA Bingshan QI Jiafu WU Guanghui REN Jianye YANG Linlong SUN Tong CHEN Shi CHEN Weichang GE Jiawang 《《地质学报》英文版》2022,96(6):2074-2092
The Pearl River Mouth Basin (PRMB) is an important area for studying the evolution of continental marginal basins in the northern South China Sea (SCS), but the structural variability and spatiotemporal rifting process remains poorly understood. This study investigates the differential structural features of the eastern, middle and western PRMB, as well as the extensional deformation laws in operation during the rifting stage, according to an integrated analysis of geometric characteristics and kinematic parameters, i.e., horizontal displacement and stretching factors of basin and crust. The PRMB underwent at least three phases of intense extension, which varied in time and space. (1) During the middle Eocene, most sags in the PRMB were intensely stretched and high-angle planar to listric boundary faults controlled the wedge-shaped stratigraphic geometry. (2) During the late Eocene-to-early Oligocene, the stratigraphic geometry of the sags was slightly wedge-shaped and continuously controlled by boundary faults, however, the extensional strength decreased relatively in the Northern depression zone, but increased in the Southern depression zone. (3) During the late Oligocene, the extension was extremely weak in the northeast PRMB, but relatively strong in the southwest PRMB, leading to tabular stratigraphic geometry in the northeast PRMB, but localized slightly wedge-shaped stratigraphic geometry in the southwest. The southwest PRMB still underwent relatively strong extension during the early Miocene. The southwest PRMB that was induced by a small-scale localized mantle convection system constantly rifted during the late Oligocene, controlled by the weak lithosphere, westward (southwestward) diachronous opening and southward jump of the ocean ridge. The applied quantitative parameters and spatiotemporal rifting process may be used as a reference with which to study the segmented continental margin rifts. 相似文献
11.
The Oligocene coals from the northeastern part of the Assam-Arakan basin show a gradual decrease in the content of moisture, volatile matter and oxygen with corresponding increase in carbon content and calorific value from the Foreland Shelf to the deeper part of the geosyncline, reflecting the coalification trends in this basin. It has been suggested that the oxygen was replaced by organic sulphur, thereby lowering the oxygen content in the coals. The coals are perhydrous in nature with a high sulphur content. The high volatile content, perhydrous nature and high sulphur content in the Oligocene coals, as well as the presence of streaky facies and a very fine clastics unit, indicate that they were probably deposited in a marine-influenced deltaic and lagoonal environment.The plots of carbon versus hydrogen on Seyler's coal band follow a trend which differs from that of Seyler's band of Carboniferous bright coals. The coalification of the Oligocene coals represents the lignitic stage, in the case of the Foreland Shelf, and near subbituminous stage in the deeper geosynclinal part of the basin. A more intense, and probably sudden, dynamic process was involved in bringing about higher coalification in Oligocene coal of the geosynclinal facies than in Foreland Shelf area. This is possibly due to intense mountain-building forces acting from the southeastern direction of the basin. 相似文献
12.
七十三万年来柴达木盆地察尔汗盐湖古气候波动的形式 总被引：21，自引：2，他引：21
本文采用14C、230Th和古地磁法,测定了察尔汗盐湖CK-6孔岩芯的年龄,并根据对该孔有机碳含量变化的研究,讨论了0.73Ma以来古气候波动的形式。初步结果表明,CK-6孔可与洛川黄土及深海沉积钻孔的气候曲线进行对比,认为全球性气候事件在青藏高原内部同样有明显的反映。 相似文献
13.
探讨有利层段的沉积与湖平面变化之间的关系,可以对湖相致密储层的勘探开发部署提供一定参考。以柴达木盆地西部尕斯地区上干柴沟组下段为例,利用自然伽马（GR）曲线资料,进行Fischer图解和铀含量（U）-有机碳（TOC）回归拟合法,重建渐新世沉积时期湖平面变化过程,结合磁化率资料,讨论了湖平面变化的气候控制作用。结果表明：（1）尕斯地区上干柴沟组下段泥质含量和TOC含量变化趋势一致,均反映其在沉积过程中经历了两次湖退和湖进过程,有利于烃源岩和储层的形成;（2）湖平面上升期形成的高水位沉积体系,对应于致密砂岩类储层中优质烃源岩的富集层段,能有效形成源-储共生配置;（3）渐新世湖平面变化受西风条件下的气候的控制,西风带来的水汽,形成相对湿润的气候条件,引起湖平面的上升,有利于烃源岩的形成,且与有利层段的沉积呈现耦合关系。 相似文献
14.
A comprehensive assessment on lake water quality was carried out in Shahu Lake, northwest China, to provide valuable information about present lake water quality for decision making. Major ions, general parameters, bacteriological parameters, organics and trace metals monitored monthly in 2014 were considered. Monitored parameters were compared with quality criteria for surface water of China, and overall water quality assessment was carried out using an entropy weighted water quality index (EWQI) based on 20 selected parameters. Lake water quality was also assessed for irrigation purpose. The results show that the lake water is of Cl·SO4–Na facies with high salinity and COD. The geochemistry of the lake water is regulated by intense evaporation and human activities. TP, TN and F? are major inorganic contaminants, with over 50% of the water samples polluted by them. Oil, mainly attributed by leaky motor tourist boats, is the major organic pollutants in the lake water, with 10 samples (37.04%) showing higher oil content than the permissible limit. The concentrations of other inorganic and organic contaminants as well as trace metals are well below the permissible limits. The present study indicates that inorganic contamination in the lake water is more severe than organic pollution. The overall lake water quality, assessed by EWQI, is poor and very poor with SO4 2?, TDS, TH and Cl? being the dominant contributing factors. The lake water is suitable for irrigation in terms of alkalinity, but is unsuitable for irrigation from the salinity point of view. Accelerating the circulation and replenishment of the lake water is an important way of reducing contaminant concentrations. This study is important in providing comprehensive information on lake water quality for decision makers and valuable reference for international lake water researchers. 相似文献
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16.
Stratigraphy and sedimentology of the Upper Cretaceous to Paleogene Kilwa Group, southern coastal Tanzania 总被引：2，自引：0，他引：2
Christopher J. Nicholas Paul N. Pearson Paul R. Bown Tom Dunkley Jones Brian T. Huber Amina Karega Jackie A. Lees Ian K. McMillan Aoife O&#x;Halloran Joyce M. Singano Bridget S. Wade 《Journal of African Earth Sciences》2006,45(4-5):431-466
The geology of southern coastal Tanzania has remained poorly understood since the first comments on its stratigraphy were made over 100 years ago. However, new field surveys combined with shallow drilling along the coast between Kilwa and Lindi are beginning to resolve the depositional history and structural evolution of this region over the past 85 Ma. Here we present the first attempt to synthesize the results of these studies to provide a coherent sedimentological, litho- and sequence stratigraphic framework, including new geological maps, for the Upper Cretaceous and Paleogene of the coastal zone.Santonian to Oligocene sediments crop out along a broad coastal belt south of the Rufiji River from the Kilwa peninsula to Lindi Creek in southern Tanzania. During 55 Ma, over 1 km of a broadly homogeneous, mid to outer shelf clay-dominated succession was deposited across the passive margin, which we define here as the Kilwa Group. This lies disconformably across the shelf on Albian marls and is itself unconformably overlain by shallow water Miocene clays and more recent limestones, sands and gravels. Four formations can be identified within the Kilwa Group on the basis of characteristic secondary lithologies and facies, described here for the first time; the Nangurukuru, Kivinje, Masoko and Pande Formations. These formations include conformable stratigraphic intervals through both the Paleocene–Eocene and Eocene–Oligocene boundaries. Within the Kilwa Group, 12 sequence stratigraphic cycles can be identified at present, demonstrating relatively uniform and continual subsidence across the margin from Santonian to Early Oligocene time. A further major bounding surface is present between the Upper Cretaceous and Paleogene, but this may become partly conformable in the Lindi area. Although the principal lithology in all formations is clay or claystone, there are more permeable intervals containing pervasive coarser siliciclastic sediments and these have yielded traces of crude oil which is likely to have migrated from lower in the succession. The Kilwa Group thus also provides important new evidence for petroleum play development in the southern coastal zone. 相似文献
17.
Several sections from the uppermost Eocene and Oligocene of northern Slovenia have been investigated with respect to sedimentary facies, foraminiferal assemblages, stable isotopes, carbonate microfacies, and palynology. The main objective was to reconstruct the paleoenvironmental history of the Paleogene Paratethys in this region of the eastern Alpine realm. The sediments exhibit a transgressive succession beginning with conglomerates, sandstones, and mudstones of fluvial and lacustrine origin followed by carbonates and muddy marls indicating marine conditions. The foraminiferal faunal changes from brackish to shallow marine to deeper marine assemblages and the distribution of the palynofloras corroborate the sedimentological results. Microfacies analysis of the limestones shows a wide variation of shallow water, generally mud-rich facies dominated by coralline algae, foraminifera, and corals. Microfaunas adapted to low-oxygen conditions indicate temporal sluggish bottom-water circulation which can be associated with high fresh-water fluxes. These results are discussed as reflecting both the global sea-level rise during the Early Oligocene and the regional tectonic and climatic evolution. 相似文献
18.
生油岩中汞的分布与有机碳及其它有机地球化学指标的关系,有可能使汞成为研究生油岩的一个指标。本文拟简述生油岩中汞的测定方法,并对已测得的资料进行初步的探讨。 相似文献
19.
M. Efendieva R. Babaev C. Johnson A. Feyzullayev Ch. Aliev 《Stratigraphy and Geological Correlation》2012,20(6):567-577
This work presents the results of biostratigraphic study of natural outcrops of the Maikop Group, which were first carried together with detailed radiometric studies in the Ganja oil and gas-bearing region, Western Azerbaijan. The paleontological research method included determination of the genus or species (depending on the preservation) of microfaunistic remains (foraminifera, ostracods, fish remains). The radiometric research method included measurements of the integral radioactivity in the field, the sampling, as well as laboratory radionuclide (spectral) analysis. As a result of our research, the stratigraphic control of variation in the radioactivity of rocks of the Maikop Group of the Ganja oil and gas-bearing region has been established. The radioactivity of Oligocene rocks is predominantly determined by potassium content. The radioactivity of the Miocene part of the section of the Maikop Group is determined by uranium-potassium contents. Within the Ganja oil and gas-bearing region, deposits of the Kotsakhurian regional stage, which are usually referred to ??barren?? formations or anoxic ??fish facies??, contain a significant number of species of benthic foraminiferal fauna. 相似文献
20.
依据丰富翔实的地层古生物资料,首次在内蒙古西部建立了比较完整的第三纪地层层序：命名或厘订了中始新统乌兰乌珠尔组、上始新统查干布拉格组、下渐新统乌兰塔塔尔组、上渐新统、下中新统乌尔图组、上中新统呼和好来组和上新统昂冈浩特组等７个地层单元;区分出了中始新世乌兰乌珠尔、晚始新世查干布拉格、早渐新世早期克克阿木、早渐新世晚期乌兰塔塔尔、晚渐新世因德里沟、早中新世乌尔图、晚中新世呼和好来和上新世昂冈浩特等８个动物群（组合）。 相似文献