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1.
从生物脂类化合物到沉积有机质的变化及其对正演烃源岩有机质形成的启示 总被引：2，自引：2，他引：0
现代海洋生物有机组分的动态变化过程是利用正演法评价海相优质烃源岩的重要中间环节, 可以为估算沉积过程中有机质的损耗提供参考.从化学组成来看, 生物体的脂类与原油成分最为接近, 而且与其他生化组分相比, 脂类的化学性质相对稳定, 可以长期保存在地层中, 因此脂类是最重要的生油母质.温度、盐度、CO2等环境条件以及生物的种类和生长阶段对生物脂类组成有重要影响, 不同环境条件和不同种类的生物对烃源岩有机质的贡献也不同.海水中的有机质在沉积过程中受原始生产力和氧化还原条件的影响.在特定生境中, 在一定的生产力范围内, 沉积有机质的通量与生产力有正相关关系.超过此范围, 沉积有机质通量与生产力关系不大.氧化条件下有机质降解速度快, 而还原条件则有利于沉积有机质的保存.生物膜的形成不仅使有机质更容易沉积, 而且降低了有机质被降解的机会.地质历史时期生物膜的识别对研究烃源岩有机质的保存具有重要意义. 相似文献
2.
The calci-mircobialite is a special carbonate buildup, which is formed due to the activities of different kinds of microbes.
Abundant microfossils preserved in the microbialite show the high-level productivity during deposition, while characteristic
sedimentary minerals and geochemical compositions suggest an anoxic marine environment for organic burial. The high-level
productivity and anoxic sedimentary environment favor the efficient preservation of organic matter and thus the formation
of source rocks. On these points, microbialites could be one of the potential hydrocarbon source rocks, awaiting further geobiological
investigation and exploration. Precambrian and some of the great transitional stages in Phanerozoic are critical periods when
microbialites were well developed. Widespread microbialites have been found in North and South China. Bitumen observed in
many outcrops of Precambrian and late Devonian microbialites further raises the possibility of the calci-microbialite as a
potential hydrocarbon source rock.
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Translated from Earth Science-Journal of China University of Geosciences, 2007, 32(6): 797-802 [译自: 地球科学-中国地质大学学报] 相似文献
3.
On the geobiological evaluation of hydrocarbon source rocks 总被引：1，自引：0，他引：1
Xie Shucheng Yin Hongfu Xie Xinong Qin Jianzhong Hu Chaoyong Yan Jiaxin Huang Junhua Zhou Lian Yang Xianghua Wang Yongbiao Xu Sihuang 《Frontiers of Earth Science》2007,1(4):389-398
Hydrocarbon source rocks are characterized by the hydrocarbon discharge, and the alteration and variation in organic compositions
and organic content due to the enhanced thermal maturation. These variations throw constraints on the application of the conventional
inversion evaluation of hydrocarbon potential by assessing the residual organic matter left in source rocks. Geobiology, probing
the interaction between the life system and the earth system, provides new principles in deciphering the whole dynamic processes
related to the organic evolution history from living biomass to organic burial. Geobiological subdisciplines, including molecular
geobiology, geomicrobiology, geoecology and biogeochemistry, offer new methodology and techniques to estimate the paleoproductivity,
depositional organics and organic burial capacity and their components. Geobiofacies, newly proposed herein, is terminologized
to define the geobiological dynamic processes through the combination of biofacies with organic facies and sedimentary facies,
and expressed by the biohabitat types, paleoproductivity, depositional and preserved organics. Geobiofacies is identified
as a useful means to create the geobiological evaluation system, which in turn rectifies the conventional evaluation system
for the marine source rocks.
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Translated from Earth Science—Journal of China University of Geosciences, 2007, 32(6): 727–740 [译自: 地球科学—中国地质大学学报] 相似文献
4.
The Late Permian Dalong Formation in Hubei, Hunan, Guizhou and Guangxi in South China could be subdivided into several sedimentary
types according to the lithology, indicative of the great spatial variations of both the lithology and sedimentary facies.
The Dalong Formation deposited during the highest transgression of Late Permian, in particular under the anaerobic and suboxic
conditions, which shows a strong linkage with the hydrocarbon source rocks. The Dalong Formation has some favorable properties
such as hydrocarbon source rocks, including the sediments deposited in highest transgression sea level, the deep slope sedimentary
environments and the low sedimentary rate, which raises the importance of the investigations on the sedimentary features,
the geochemical properties and their relationship with the oil potential.
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Translated from Earth Science—Journal of China University of Geosciences, 2007, 32(6): 774–780 [译自: 地球科学—中国地质大学学报] 相似文献
5.
On the basis of the results of hydropyrolysis simulations for about 90 different types of immature to mature source rocks
selected from about 5 000 marine source rocks in China, along with the natural thermal evolution profiles, the following conclusions
were obtained. (1) Total organic carbon (TOC) content of excellent marine source rocks does not change obviously when Ro < 0.8% or Ro > 1.3%, and the residual TOC content is decreasing gradually with the maturity increase at 0.8% < Ro < 1.3%. (2) At the high-post mature stage (Ro > 1.3%), the decreased maximums of residual TOC content for the kerogen of sapropel (I), II1, and II are usually 40%, 32% and 24%, respectively, and their TOC restitution coefficient is, respectively, 1.68, 1.48 and
1.32. (3) Both the TOC decreasing amplitude and the restitution coefficient decrease gradually with the decrease of TOC content
for the source rocks with low organic matter abundance (usually 0.3% < TOC < 1.0%). The TOC restitution coefficients are,
respectively, 1.20 and 1.0, when 0.3% < TOC < 0.5% and TOC < 0.3%. (4) TOCres of solid bitumen and shale with high organic matter abundance (TOC > 30%) also require no restitution at the high mature
stage. Such kind of TOC restitution is further supported by the coincidence of the decrease of residual TOC with the decreasing
of S1 + S2 and the increasing of hydrocarbon quantity during the experimental simulation of hydrocarbon generation and expulsion for
marine source rocks (0.3% < TOC < 30%) in natural thermal evolution profiles.
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Translated from Earth Science—Journal of China University of Geosciences, 2007, 32(6): 853–860 [译自: 地球科学—中国地质大学学报] 相似文献
6.
To understand the potential mechanism of marine extremophiles participating in the formation and the evolution of hydrocarbon
resources in marine extreme environments, some typical kinds of extremophiles and their distributions in marine hydrothermal
and cold vents are discussed and evaluated respectively. The potential relationship between extremophile activities and hydrocarbon
resources in marine extreme environments are then discussed in details. It could be now preliminary concluded that archaea
and bacteria are the two main kinds of extremophiles in marine extreme environments. The dominating microbe communities in
hydrothermal vents are heterotrophic zymogens, sulfate reducers and methanogens, while the ANME-2 group (Methanosarcinales) surrounded by sulfate-reducing bacteria and ANME-1 group dominate in cold vents. Marine extremophiles would be able to use
CH4 and H2S to synthesize energy for metabolism and to support food chains for other unique macrobiota nearby, which together present
a high abundance but a low diversity with distinct characteristics of horizontal and vertical distributions. Marine extremophiles
might play an important role either directly or indirectly in the processes of hydrocarbon formation and subsequent alteration,
and could indicate the evolution of hydrocarbon resources in marine extreme environments. Our research thus has a great significance
both in theoretical approach of potential hydrocarbon resources formed by marine extremophile activities and in practical
exploration of the potential hydrocarbonsource sedimentary layers formed in the Earth history or the potential strata in southern
China.
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Translated from Earth Science—Journal of China University of Geosciences, 2007, 32(6): 781–788 [译自: 地球科学—中国地质大学学报] 相似文献
7.
The paper presents the molybdenum isotope data, along with the trace element content, to investigate the geochemical behavior
of authigenic Mo during long-term burial in sediments in continental margin settings of the Yangtze block, as well as their
indication to the burial of original organic carbon. The burial rate of original organic carbon was estimated on the basis
of the amount of sedimentary sulfur (TS content), whilst the carbon loss by aerobic degradation was estimated according to
calculated Mn contents. On these points, the original organic carbon flux was calculated, exhibiting a large range of variation
(0.17–0.67 mmol/m2/day). The strong correlation between sedimentary Mo isotope values and organic carbon burial rates previously proposed on
the basis of the investigations on modern ocean sediments, was also used here to estimate the organic carbon burial rate.
The data gained through this model showed that organic carbon burial rates have large variations, ranging from 0.43–2.87 mmol/m2/day. Although the two sets of data gained through different geochemical records in the Yangtze block show a deviation of
one order of magnitude, they do display a strong correlation. It is thus tempting to speculate that the Mo isotope signature
of sediments may serve as a tracer for the accumulation rate of original organic carbon in the continental margin sediments.
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Translated from Earth Science—Journal of China University of Geosciences, 2007, 32(6) [译自: 地球科学—中国地质大学学报] 相似文献
8.
Impact of Montmorillonite and Calcite on Release and Adsorption of Cyanobacterial Fatty Acids at Ambient Temperature 总被引：1，自引：0，他引：1
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. 相似文献
9.
The study of oil geologic anomalies is a new area of petroleum geology. Using the evidence weight method, we selected tectonic,
hydrocarbon abundance of source rock, thickness of source rock, level of reservoir, complexity of reservoir, degree of mineralization
of formation water as the evidence layer to evaluate the favorable zones of pool forming in the Lower Paleozoic in the north
edge of the Middle and Lower Yangtze areas. Finally, we integrated our results with the petroleum geology of this area and
concluded that the North Sichuan basin, the western area of Hubei and the eastern area of Chongqing and parts of the Lower
Yangtze are the most profitable areas for exploration in the north edge of the Lower and Middle Yangtze areas.
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Translated from Journal of Jilin University (Earth Science Edition), 2007, 37(3): 458–462 [译自: 吉林大学学报(地球科学版)] 相似文献
10.
Northeast Sichuan basin is a Mesozoic-Cenozoic basin in the northern margin of the Yangtze plate which has a complex tectonic
background and hydrocarbon accumulation history. By means of the analysis method of wave processes, major cycles of sedimentary
wave process in this basin have been studied. The results show that there are five-order cycles corresponding to 760, 220,
100, 35 and 20 Ma respectively, two first-order sedimentary cycles (220 Ma) and four secondorder sedimentary cycles (100 Ma).
The authors find that the second-order sedimentary cycles are well matched with reservoir formation cycles through studying
the relationship between second-order sedimentary cycles and reservoir formation cycles, and divide three reservoir formation
cycles in this basin.
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Translated from Journal of Jilin University (Earth Science Edition), 2007, 37(3): 513–518 [译自: 吉林大学学报(地球科学版)] 相似文献
11.
Su Wenbo Li Zhiming Ettensohn F. R. Johnson M. E. Huff W. D. Wang Wei Ma Chao Li Lu Zhang Lei Zhao Huijing 《Frontiers of Earth Science》2007,1(4):470-481
It is known that high-quality, black-shale source rocks occur in the uppermost Ordovician Wufeng Formation and in the lowermost
Silurian Longmaxi Formation in South China. Hence, it is important to understand their lithostratigraphy and the controls
on their deposition. A review of lithostratigraphic criteria for subdividing the two adjacent formations provides new regional
correlations between the formations and related stratigraphic successions and facies. Both the black shales and the related,
overlying flysch deposits at the Ordovician-Silurian transition in South China appear to have migrated northwestward in time
and space, reflecting probable flexural control in a foreland basin that developed in response to subduction-type orogeny
southeast of the Yangtze block. The black shales also contain K-bentonites from explosive, felsic-intermediate volcanism,
the distribution of which also supports orogeny to the southeast. Finally, the analysis of sequence stratigraphy, which shows
that the initiation of transgressive system tracts (TST) and condensed section (CS) in the related third-order sequences coincided
with the two black-shale horizons respectively, indicates that the main controlling factors for the deposition of the Ordovician-Silurian
black shales in South China are (1) northwestwardly migrating, foreland-basin subsidence caused by deformational loading related
to episodic accretion of the Cathaysia block to the Yangtze block during this period, and (2) the anoxic, sediment-starved
water column caused by rapid rise of the sea-level during the two successive phases of third-order global sea-level rise near
the Ordovician-Silurian transition in South China. In future exploration for hydrocarbon source rocks in the area, it is important
to consider likely flexural and eustatic causes for subsiding, deep, anoxic seas in recognizing other source rock intervals,
and our understanding of the Wufeng and Longmaxi formations may serve as models for future source rock exploration.
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Translated from Earth Science—Journal of China University of Geosciences, 2007, 32(6): 818–827 [译自: 地球科学—中国地质大学学报] 相似文献
12.
海相烃源岩的正反演对比分析 总被引：4，自引：0，他引：4
海相优质烃源岩有效的评价体系是海相地层油气勘探开发中的关键问题之一.沉积盆地内保存的残余有机质从生物物质到烃源岩的演化过程经历了两个阶段, 即从生物物质到沉积有机质的形成阶段和从沉积有机质到残余有机质的烃源岩形成阶段, 后者包括沉积有机质在未熟阶段经历生物化学作用成为埋藏有机质和在成熟-过成熟阶段经历热解作用成为残余或风化残余有机质两个亚阶段.烃源岩反演分析是利用残余或风化残余有机质的量来推断埋藏有机质的量或者原始生烃潜力.而正演分析则是根据沉积物沉积环境、生物物质及其介质物理化学条件特征运用地球生态学、地球微生物学、分子地球生物学和生物地球化学方法推断沉积有机质的量, 甚至推断埋藏有机质的量, 进而评估烃源岩的原始生烃潜力, 也就是利用生物生产力和保存环境等综合分析沉积有机质的量.正反演对比分析相互验证和相互补充, 更好地揭示了烃源岩基本特征, 为海相优质烃源岩的预测和评价提供了有效的研究方法. 相似文献
13.
To decipher the origin of oxygen-deficient shelfal deposits is significant for tracing the distribution of marine source rocks
and interpreting the evolution of depositional environment. The origin of the Middle Permian Chihsia Formation in South China
remains a puzzle for long with its evident oxygen-deficient features but diverse benthos. This paper shows a typical Chihsian
depositional rhythm composed of the massive and the laminated limestones with ecological and geochemical features. Massive
bioclastic limestone from the rhythm was aerobic in paleoxygenation condition indicated by both the ecological and geochemical
features. However, a contradictory oxygenation was inferred for the “laminated” counterpart from the rhythm, with the ecological
signal being aerobic and the geochemical one being anoxic. The difference in ecological and geochemical indications was interpreted
as the instability of paleoxygenation condition in shelf environments, caused by an enhanced paleoproductivity. Rhythmic occurrence
of the oxygen-deficient condition might have been stemmed from paleo-Tethyan paleocurrents flowing across South China.
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Translated from Earth Science—Journal of China University of Geosciences, 2007, 32(6): 789–796 [译自: 地球科学—中国地质大学学报] 相似文献
14.
南黄海盆地二叠系烃源岩孢粉相特征及其形成环境 总被引：1，自引：0，他引：1
以沉积环境控制烃源岩发育理论为指导,应用孢粉相分析方法,以南黄海盆地二叠系大隆组、龙潭组和栖霞组烃源岩层段为研究对象,对典型钻井剖面的孢粉及沉积有机屑进行系统的分析。根据沉积有机屑的丰度特征和组分类型,探讨三套烃源岩的形成环境,初步评价其生烃潜力。研究结果表明,利用孢粉相分析方法,可以有效地对高成熟海相烃源岩的生烃潜力和形成环境进行客观评价:栖霞组为缺氧远陆架沉积环境,以无定形有机质为主,水体分层缺氧,是烃源岩形成的有利环境;大隆组为缺氧和少氧的陆架环境,也较有利于烃源岩的形成,生烃潜力较栖霞组差;龙潭组煤质型有机质较为丰富,为充氧的陆架区,以陆源输入为主,沉积区水体较浅,含氧量高,不利于富氢烃源岩的形成。 相似文献
15.
Zheng Jianping Yu Chunmei Yuan Xiaoping Yin Li Jiao Shujuan Tang Huayun Zhang Zhihai Lu Fengxiang 《Frontiers of Earth Science》2007,1(1):37-43
A petrochemical analysis was undertaken of peridotitic xenoliths in volcanic rocks that erupted from the Paleozoic to the
Cenozoic within the eastern part of the North China craton, and the peridotites as tectonic intrusion in the Early Mesozoic
from the Sulu orogen. The results show that the cratonic mantle, which was refractory and existed when the kimberlites intruded
in the Paleozoic, had almost been replaced by the newly accreted fertile lithospheric mantle during the Mesozoic-Cenozoic.
The erosion, metasomatism, and intermingling caused by the accreted asthenospheric material acting on the craton mantle along
the weak zone and deep fault (such as the Tanlu fault) in the existing lithosphere resulted in the lithospheric thinning at
a larger scale 100 Ma ago (but later than 178 Ma). The largest thinning would be in the Eogene. The upwelling asthenospheric
material transformed into accreted lithospheric mantle due to the asthenospheric temperature falling in the Neogene (leading
to relatively slight lithospheric incrassation), and finally accomplished mantle replacement. The peridotitic body in the
Sulu orogen represents the products spreading from the modified cratonic lithospheric mantle.
Translated from Earth Science—Journal of China University of Geosciences, 2006, 31(1): 49–56 [译自: 地球科学—中国地质大学学报] 相似文献
16.
生烃动力学、同位素动力学常用于烃源岩评价、油气源对比研究中.生烃动力学参数结合盆地热史,可恢复烃源岩在任一时代的生烃史,对构造复杂盆地的二次生烃研究具有独特的优势.利用生烃动力学方法可以实现有机质总量的恢复,在此基础上对高-过成熟样品原始有机质丰度是否有必要恢复进行了讨论;而基于生烃动力学的油气源对比综合考虑热史、成藏期次、成藏过程等各种地质参数对烃源岩生烃的影响,是一种动态的研究方法. 相似文献
17.
18.
Deep-seated gas is defined in this paper as natural gas generated under the combined action of high temperature, high pressure,
and environment media. As to organic matter vertical evolution, deep-seated gas is natural gas, which is generated and deposited
under the position of an oil generation window. Deep-seated gas exploration is an important potential field for oil-gas exploration.
Also, it is an inexorable trend to the further development of oil and gas provinces. In this paper, the authors will examine
and distinguish the concept of deep-seated gas, and discuss the distribution and gas source of deep-seated gas. It is pointed
out that kerogen, assemble dissoluble organic matter and disperse dissoluble organic matter all have contributed to deep-seated
gas generation, especially disperse dissoluble organic matter in composite and superimposed sedimentary basin. In the end,
according to the structural evolution and hydrocarbon source rock depositional distribution, the distribution of deep-seated
gas in China is predicted.
Translated from Geology in China, 2006, 33(5): 937–943 [译自: 中国地质] 相似文献
19.
20.
By combining the carbon cycle model with the records of carbonate and organic (kerogen) carbon isotope, this paper presents
the calculation of the fraction of organic carbon burial (f
org) of beds 23–40 at the global boundary stratotype section and point (GSSP) of the Permian-Triassic boundary at Meishan, Zhejiang
Province. The resulting calculation produces two episodes of f
org maxima observed to occur at beds 23–24 and 27–29, which respectively corresponds to the two episodic anoxic events indicated
by the flourish of green sulfur bacteria. Two episodic f
org minima occurred at beds 25–26 and 32–34, generally coincident with the flourish of cyanobacteria (bed 26 and upper part of
beds 29 to 34) as shown by the high value of 2-melthyhopnoanes. It appears that the f
org is related to the redox conditions, with greater f
org values observed under the reductive condition. The relationship between f
org and the total organic carbon (TOC) content was complex. The f
org value was low at some beds with a high TOC content (such as bed 26), while high observed at some beds with a low TOC content
(e.g. bed 27). This association infers the important contribution of primary productivity to the TOC content. The original
organic burial could be thus calculated through the configuration of the function of the primary productivity and f
org, which can be used to correct the residual TOC measured today. This investigation indicates that compiling the organic-inorganic
carbon isotopes with the carbon cycle model favors to understand the fraction of organic carbon burial, providing information
for the reconstruction of the coupling among biota, environments and organic burial.
Journal of China University of Geosciences, 2007, 32(6): 767–773 [译自: 地球科学—中国地质大学学报] 相似文献