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Biological and Molecular Geochemical Evidence for Dinoflagellate Ancestors in the Upper Sinian-Cambrian 被引量:8
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作者 J.Mike MOLDOWAN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第4期740-747,共8页
Dinoflagellates are single celled organisms that reflect the ecological conditions in modern oceans and lakes. Their earliest undisputed fossil record suggests that dinoflagellates originated from the Middle Triassic ... Dinoflagellates are single celled organisms that reflect the ecological conditions in modern oceans and lakes. Their earliest undisputed fossil record suggests that dinoflagellates originated from the Middle Triassic (c. 240 Ma ago). However, the presence of molecular biomarkers (dinosterane, 4α-methyl-24-ethylcholestane and tria-romatic dinosteroids) in rock extracts and coccoid dinoflagellate fossils from the upper Sinian to Cambrian of the Tarim basin confirms the hypothesis that dinoflagellates have an ancient origin, and predate the oldest undisputed dinoflagellate fossils at least by 300 Ma, as early as the late Sinian-Cambrian. 展开更多
关键词 DINOFLAGELLATES dinosterane triaromatic dinosteroids CAMBRIAN
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Estimating plant crown transpiration and water use efficiency by vegetative reflectance indices associated with chlorophyll fluorescence 被引量:2
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作者 Hidenori Furuuchi Michael W. Jenkins +2 位作者 Randy S. Senock James L. J. Houpis James C. Pushnik 《Open Journal of Ecology》 2013年第2期122-132,共11页
This research developed estimates of plant crown transpiration and water-use-efficiency using reflectance and derivative indices extracted from remotely sensed chlorophyll fluorescence measurements under natural condi... This research developed estimates of plant crown transpiration and water-use-efficiency using reflectance and derivative indices extracted from remotely sensed chlorophyll fluorescence measurements under natural conditions. Diurnal changes of leaf-level gas exchange (carbon assimilation rate (A), stomatal conductance (gs), transpiration rate (E)), chlorophyll fluorescence and canopy-scale remote sensing were measured on top crown of valley oak (Quercus lobata) in the foothills of central California, USA. The results indicated Q. lobata experienced saturating irradiance (PAR), which induced photoinhibition indicated by a decrease in the quantum efficiency of photosystem II (r2 = 0.648 with Fv ′/Fm′ and r2 = 0.73 with FPSII) and open reaction centers (qP;r2 = 0.699). The excess absorbed quantum energy was dissipated as heat through the Xanthophyll cycle and other processes (photorespiration and the water-water cycle) rather than energy emission as steady state chlorophyll fluorescence (Fs). An increase in leaf temperature caused by the activity of Xanthophyll cycle was correlated to a decrease in Fs (r2 = 0.381) and an increase in evaporative cooling through E (r2 = 0.800) and water use efficiency (WUE;r2 = 0.872). 展开更多
关键词 CROWN TRANSPIRATION Remote Sensing CHLOROPHYLL Fluorescence Reflectance QUERCUS lobata
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Mud volcano origin of the Mottled Zone,South Levant 被引量:1
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作者 Igor Novikov Yevgeny Vapnik Inna Safonova 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第5期597-619,共23页
The Mottled Zone(MZ) or Hatrurim Formation,which occurs near the Levantine Transform in the South Levant,has been studied during the last 150 years but its origin remains debatable.Mottled Zone Complex/Complexes(MZ... The Mottled Zone(MZ) or Hatrurim Formation,which occurs near the Levantine Transform in the South Levant,has been studied during the last 150 years but its origin remains debatable.Mottled Zone Complex/Complexes(MZC/MZCs) consist of brecciated carbonate and low-temperature calcium-hydro-silicate rocks,which include unusual high- and ultra-high-temperature low-pressure(HT-LP) meta-morphic mineral assemblages.The MZ has been regarded as a product of combustion of bituminous chalks of the Ghareb Fm.of Cretaceous(Maastrichtian) age.In this paper we present detailed geographic, geomorphologic,structural and geological data from the MZCs of the South Levant,which show that the MZCs cannot be stratigraphically correlated with the Ghareb Fm.,because MZC late Oligocene-late Pleistocene deposits occur within or unconformable i.e.,with stratigraphic hiatus,overlap both the late Cretaceous and,in places,Neogene stratigraphic units.We propose an alternative model for the formation of MZCs by tectonically induced mud volcanism during late Oligocene-late Pleistocene time. This model explains(i) the presence of dikes and tube-like bodies,which consist of brecciated exotic clastic material derived from stratigraphically and hypsometrically lower horizons;(ii) mineral assemblages of sanidinite facies metamorphism;(iii) multi-stage character of HT-LP pyrometamorphism;and (iv) multi-stage low-temperature hydrothermal alteration.High temperatures(up to 1500℃) mineral assemblages resulted from combustion of hydrocarbon gases of mud volcanoes.Mud volcanism was spatially and structurally related to neotectonic folds and deformation zones formed in response to opening of the Red Sea rift and propagation of the Levantine Transform Fault.Our model may significantly change the prospects for oil-and-gas deposits in the region. 展开更多
关键词 HT-LP sanidinite facies metamorphism GEOMORPHOLOGY Dead Sea Levantine Transform NEOTECTONICS Hydrocarbon traps
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Raman spectrum study of graphite irradiated by swift heavy ions
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作者 翟鹏飞 刘杰 +5 位作者 曾健 姚会军 段敬来 侯明东 孙友梅 Ewing Rodney Charles 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期361-366,共6页
Highly oriented pyrolytic graphites are irradiated with 40.5-Me V and 67.7-Me V ^112Sn-ions in a wide range of fluences: 1×10^11 ions/cm^2–1×10^14ions/cm^2. Raman spectra in the region between 1200 cm^-1 a... Highly oriented pyrolytic graphites are irradiated with 40.5-Me V and 67.7-Me V ^112Sn-ions in a wide range of fluences: 1×10^11 ions/cm^2–1×10^14ions/cm^2. Raman spectra in the region between 1200 cm^-1 and 3500cm^-1 show that the disorder induced by Sn-ions increases with ion fluence increasing. However, for the same fluence, the amount of disorder is greater for 40.5-Me V Sn-ions than that observed for 67.7-Me V Sn-ions, even though the latter has a slightly higher value for electronic energy loss. This is explained by the ion velocity effect. Importantly, ~ 3-cm^-1frequency shift toward lower wavenumber for the D band and ~ 6-cm^-1 shift toward lower wavenumber for the 2D band are observed at a fluence of 1×10^14 ions/cm^2, which is consistent with the scenario of radiation-induced strain. The strain formation is interpreted in the context of inelastic thermal spike model, and the change of the 2D band shape at high ion fluence is explained by the accumulation of stacking faults of the graphene layers activated by radiation-induced strain around ion tracks. Moreover,the hexagonal structure around the ion tracks is observed by scanning tunneling microscopy, which confirms that the strains near the ion tracks locally cause electronic decoupling of neighboring graphene layers. 展开更多
关键词 Raman spectroscopy swift heavy ions highly oriented pyrolytic graphite STRAIN ion velocity effect
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Exploring the edge of a natural disaster
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作者 Michael W. Jenkins Dan J. Krofcheck +2 位作者 Rachel Teasdale James Houpis James Pushnik 《Open Journal of Ecology》 2012年第4期222-232,共11页
Natural geological, chronic and acute release of volcanic gases can have a dramatic impact on vegetative ecosystems and potential impact on regional agriculture and human health. This research incorporates a series of... Natural geological, chronic and acute release of volcanic gases can have a dramatic impact on vegetative ecosystems and potential impact on regional agriculture and human health. This research incorporates a series of observations using leaf level gas exchange, chlorophyll fluorescence and remotely sensed reflectance measurements of vegetation experiencing chronic exposure to volcanic gas emissions;to develop techniques for monitoring the relative health of vegetation along the edge of an acute vegetative kill zone of a natural disaster and potential preeruption vegetation physiology. Experiments were conducted along an elevation gradient that corresponds to the SO2 gradient on vegetation along the south flank of Volcán Turrialba, Costa Rica. This study site is a natural environment with high volcanic degassing activity with significant SO2 emissions (n/d-0.281 ppm). Corresponding to an SO2 gradient, a substantial increase in CO2 concentration of (430-517 ppm) was identified. We further show the physiological interactions of SO2 and CO2 have on vegetation along the kill zone of this natural disaster can be assessed by examining the SO2/CO2 ratios. The physiological indices tested and relationships among measurements emphasized in this research will add to the assessment of the impact atmospheric volcanic gas emissions have on the physiology of surrounding vegetation as well as advance the capability of remotely sensed environmental stress in natural settings. 展开更多
关键词 Carbon Dioxide CHLOROPHYLL Fluorescence LEAF Level GAS Exchange Natural DISASTER Remote Sensing SULPHUR Dioxide VOLCANIC GAS Emissions
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Identifying Non-Darcian Flow and Non-Fickian Pressure Propagation in Field-Scale Discrete Fracture Networks
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作者 Bingqing Lu Yong Zhang +4 位作者 Yuan Xia Donald M. Reeves Hongguang Sun Dongbao Zhou Chunmiao Zheng 《Journal of Geoscience and Environment Protection》 2018年第5期59-69,共11页
Non-Darcian flow has been well documented for fractured media, while the potential non-Darcian flow and its driven factors in field-scale discrete fracture networks (DFNs) remain obscure. This study conducts Monte Car... Non-Darcian flow has been well documented for fractured media, while the potential non-Darcian flow and its driven factors in field-scale discrete fracture networks (DFNs) remain obscure. This study conducts Monte Carlo simulations of water flow through DFNs to identify non-Darcian flow and non-Fickian pressure propagation in field-scale DFNs, by adjusting fracture density, matrix hydraulic conductivity, and the general hydraulic gradient. Numerical simulations and analyses show that interactions of the fracture architecture with the hydraulic gradient affect non-Darcian flow in DFNs, by generating and adjusting complex pathways for water. The fracture density affects significantly the propagation of hydraulic head/pressure in the DFN, likely due to fracture connectivity and flow channeling. The non-Darcian flow pattern may not be directly correlated to the non-Fickian pressure propagation process in the regional-scale DFNs, because they refer to different states of water flow and their controlling factors may not be the same. Findings of this study improve our understanding of the nature of flow in DFNs. 展开更多
关键词 DISCRETE FRACTURE Networks Non-Darcian FLOW Non-Fickian PRESSURE Propa-gation
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含柯石英锆石的SHRIMP U-Pb定年:胶东印支期超高压变质作用的证据 被引量:47
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作者 杨经绥 许志琴 +4 位作者 吴才来 刘福来 史仁灯 J.Wooden Maruyama 《地质学报》 EI CAS CSCD 北大核心 2002年第3期354-372,共19页
苏鲁超高压变质带的形成时代究竟是印支期还是新元古代争议始终很大。对山东胶南地区超高压变质带中超镁铁岩和榴辉岩的锆石激光拉曼、阴极发光和离子探针原位定年的研究获得超高压变质作用发生的时代为印支期。其中超镁铁岩含柯石英锆... 苏鲁超高压变质带的形成时代究竟是印支期还是新元古代争议始终很大。对山东胶南地区超高压变质带中超镁铁岩和榴辉岩的锆石激光拉曼、阴极发光和离子探针原位定年的研究获得超高压变质作用发生的时代为印支期。其中超镁铁岩含柯石英锆石的年龄为221±12Ma,该深成岩侵位时代为新元古代(581±44Ma)。此外,锆石中另有约400Ma年龄记录,可能代表岩石形成后另有一期热事件。榴辉岩的下交点年龄为228±29 Ma,与超镁铁岩含柯石英锆石年龄一致,代表超高压变质时代;上交点为中元古代(1821±19Ma),代表原岩年龄,后者与其片麻岩围岩时代相一致,说明榴辉岩是原位俯冲。 展开更多
关键词 HSRIMP 柯石英 榴辉岩 超镁铁岩 苏鲁超高压变质带 印支期 山东 锆石 超高压变质作用
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Distribution and characterization of C_(31) sterane from cretaceous sediments and oils,Songliao Basin,China 被引量:2
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作者 J. M. Moldowan 《Chinese Science Bulletin》 SCIE EI CAS 1999年第6期560-563,共4页
Relatively high abundance of C<sub>31</sub> steranes has been identified from cretaceous source rocks and crude oils in the Songliao Basin, China. C<sub>31</sub> steranes which occur as ten iso... Relatively high abundance of C<sub>31</sub> steranes has been identified from cretaceous source rocks and crude oils in the Songliao Basin, China. C<sub>31</sub> steranes which occur as ten isomers were tentatively identified as 4, 22, 23, 24-tetrametyhlcholestane based on their retention time and mass spectrum.They bear a lower thermal stability and occur as important components in the immature oils of Chaochang region because they have three-methyl groups in their side chain. The relatively high abundance of C<sub>31</sub> steranes in the samples can indicate the source input of some special algae in the brackish and saline environment. Therefore they can be used as very useful biomarkers for organic facies analysis and oil correlation. Their biological source perhaps related to the dinoflagellate such as G. foliaceum and P. foliaceum. The gorgostanol are considered as possible precursors for the putative C<sub>31</sub>4methyl sterane which formed in the stage of diagenesis. 展开更多
关键词 C31 STERANE ancient environment ALGAE oil correlation.
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Operculina and Neoassilina:A Revision of Recent Nummulitid Genera Based on Molecular and Morphological Data Reveals a New Genus 被引量:2
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作者 Maria Holzmann Johann Hohenegger +4 位作者 Laure Apothéloz-Perret-Gentil Raphael Morard Sigal Abramovich Danna Titelboim Jan Pawlowski 《Journal of Earth Science》 SCIE CAS CSCD 2022年第6期1411-1424,共14页
The genus Operculina,a large symbiont-bearing benthic foraminifer,is characterized by high morphological variability showing thick involute to intermediate semi-involute to flat evolute tests.Different morphotypes are... The genus Operculina,a large symbiont-bearing benthic foraminifer,is characterized by high morphological variability showing thick involute to intermediate semi-involute to flat evolute tests.Different morphotypes are either considered as ecophenotypes or distinct species.In order to test the hypothesis of ecophenotypes versus different species,a single cell high throughput sequencing approach was applied to assess the interspecific diversity of Operculina.This results in two groups of ribotypes,one corresponding to Operculina ammonoides/Operculina discoidalis,the other containing Operculina complanata/Operculina elegans.These groups can also be separated morphologically.Therefore,O.complanata and O.elegans represent a single species and the latter can be regarded as a junior synonym of O.complanata.Operculina ammonoides and O.discoidalis also form a single species,which makes the latter a junior synonym of O.ammonoides.Because generic differences in Operculina species are manifested in morphology and molecular genetics,the genus Neoassilina with the designated species Neoassilina ammonoides is installed.Additional analysis of ribosomal SSU rDNA data of eight recent nummulitid genera confirms the obtained high troughput sequencing results and further shows that Palaeonummulites venosus builds a clade with O.complanata that branches at the base of other Nummulitidae containing Planostegina,Planoperculina,Cycloclypeus,Heterostegina,Operculinella and Neoassilina. 展开更多
关键词 Operculina Neoassilina Nummulitidae interspecific diversity SSU rDNA MORPHOLOGY
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High-pressure storage of hydrogen fuel: ammonia borane and its related compounds 被引量:1
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作者 Yu Lin Wendy L.Mao 《Chinese Science Bulletin》 SCIE EI CAS 2014年第36期5235-5240,共6页
As a promising candidate material for hydrogen storage, ammonia borane(NH3BH3) has attracted significant interest in recent years due to its remarkably high hydrogen content. Subjecting this material to high pressure ... As a promising candidate material for hydrogen storage, ammonia borane(NH3BH3) has attracted significant interest in recent years due to its remarkably high hydrogen content. Subjecting this material to high pressure not only enables the formation of novel phases and compounds with exotic properties, but also improves our basic understanding of material's behavior at different levels of atomic and molecular interactions. This review focuses on the perspective of high-pressure chemical hydrogen storage related to NH3BH3-based materials. Four main aspects are discussed: the structures and bonding of NH3BH3 over a wide pressure–temperature space, thermolysis of NH3BH3 at high pressure, the formation of a novel high-pressure H-rich compound as a result of storage of additional molecular H2 in NH3BH3, and the potential rehydrogenation of the thermally decomposed NH3BH3 under the extreme of pressure. 展开更多
关键词 高压储存 化合物 硼烷 氢燃料 高压力 相互作用 分子间
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Zircon SHRIMP dating of granite from Qaidamshan,NW China 被引量:15
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作者 WU Cailai YANG Jingsui +6 位作者 J.Wooden J.G.Liou LI Haibing SHI Rending MENG Fancong H.Persing A.Meibom 《Chinese Science Bulletin》 SCIE EI CAS 2002年第5期418-422,共5页
Zircon SHRIMP dating from Qaidamshan granite shows that the granite age is 446 Ma, similar to that of eclogite in the UHP belt. We think that both granite and eclogite may be formed at different stages during tectonic... Zircon SHRIMP dating from Qaidamshan granite shows that the granite age is 446 Ma, similar to that of eclogite in the UHP belt. We think that both granite and eclogite may be formed at different stages during tectonic evolution of this area. Together with other studies we suggested that the collision of ocean and continent plates may occur at the early Caledonian in this area, forming the eclogite, and the collision of continent and continent plates at the late Caledonian, forming the Qaidanishan granite with the zircon SHRIMP age of 446 Ma. 展开更多
关键词 GRANITE ZIRCON SHRIMP DATING Qaidamshan.
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Metal-dependent anaerobic methane oxidation in marine sediment:insights from marine settings and other systems 被引量:7
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作者 Lewen Liang Yinzhao Wang +1 位作者 Orit Sivan Fengping Wang 《Science China(Life Sciences)》 SCIE CAS CSCD 2019年第10期1287-1295,共9页
Anaerobic oxidation of methane(AOM) plays a crucial role in controlling global methane emission. This is a microbial process that relies on the reduction of external electron acceptors such as sulfate, nitrate/nitrite... Anaerobic oxidation of methane(AOM) plays a crucial role in controlling global methane emission. This is a microbial process that relies on the reduction of external electron acceptors such as sulfate, nitrate/nitrite, and transient metal ions. In marine settings, the dominant electron acceptor for AOM is sulfate, while other known electron acceptors are transient metal ions such as iron and manganese oxides. Despite the AOM process coupled with sulfate reduction being relatively well characterized,researches on metal-dependent AOM process are few, and no microorganism has to date been identified as being responsible for this reaction in natural marine environments. In this review, geochemical evidences of metal-dependent AOM from sediment cores in various marine environments are summarized. Studies have showed that iron and manganese are reduced in accordance with methane oxidation in seeps or diffusive profiles below the methanogenesis zone. The potential biochemical basis and mechanisms for metal-dependent AOM processes are here presented and discussed. Future research will shed light on the microbes involved in this process and also on the molecular basis of the electron transfer between these microbes and metals in natural marine environments. 展开更多
关键词 ANAEROBIC methane oxidation metal-AOM MARINE sediment ARCHAEA electron transfer
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阿尔金断裂带印支期走滑活动的地质及年代学证据 被引量:68
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作者 李海兵 杨经绥 +6 位作者 许志琴 吴才来 万渝生 史仁灯 J. G. Liou P. Tapponnier T. R. Ireland 《科学通报》 EI CAS CSCD 北大核心 2001年第16期1333-1338,共6页
阿尔金断裂带中段出露一套花岗质和角闪质糜棱岩及糜棱岩化岩石, 初步研究表明这套岩石是左行走滑剪切过程中同构造深熔作用的产物, 是韧性转换挤压作用的结果. 同剪切深熔作用形成的花岗质和角闪质糜棱岩中, 分选出深熔成因的长柱状锆... 阿尔金断裂带中段出露一套花岗质和角闪质糜棱岩及糜棱岩化岩石, 初步研究表明这套岩石是左行走滑剪切过程中同构造深熔作用的产物, 是韧性转换挤压作用的结果. 同剪切深熔作用形成的花岗质和角闪质糜棱岩中, 分选出深熔成因的长柱状锆石和残余的变质成因次浑圆柱状锆石两种类型. 单颗粒锆石离子探针(SHRIMP)定年测得两组年龄, 其中461~547 Ma年龄组为次浑圆柱状残余的变质成因锆石的年龄, 另一组239~244 Ma为长柱状深熔型锆石的年龄, 这种锆石在岩石中定向排列, 其晶体长轴方向与拉伸线理方向一致, 代表走滑剪切过程中的构造应力方向. 测得同样糜棱岩样品中定向生长的角闪石的-(40)Ar--(39)Ar年龄为223~226 Ma. 以上地质学及年代学证据表明同构造深熔作用发生在印支期, 说明阿尔金断裂带至少在印支期发生了强烈的走滑运动. 展开更多
关键词 阿尔金断裂带 同构造深熔作用 糜棱岩 锆石定向 走滑活动 地质学 年代学
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柴达木山花岗岩锆石SHRIMP定年 被引量:42
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作者 吴才来 杨经绥 +5 位作者 J.Wooden J.G.Liou 李海兵 孟繁聪 H.Persing A.Meibom 《科学通报》 EI CAS CSCD 北大核心 2001年第20期1743-1747,共5页
锆石SHRIMP定年研究表明,祁连南缘柴达木山花岗岩与超高压榴辉岩是构造演化过程中不同阶段形成的,即加里东早期,该区存在洋壳-陆壳碰撞,形成榴辉岩;加里东晚期,存在陆壳-陆壳的碰撞,形成了该花岗岩体.该岩体的SHRI... 锆石SHRIMP定年研究表明,祁连南缘柴达木山花岗岩与超高压榴辉岩是构造演化过程中不同阶段形成的,即加里东早期,该区存在洋壳-陆壳碰撞,形成榴辉岩;加里东晚期,存在陆壳-陆壳的碰撞,形成了该花岗岩体.该岩体的SHRIMP年龄为446Ma. 展开更多
关键词 花岗岩 锆石 SHRIMP定年 柴达木山 超高压榴辉岩 构造演化 洋壳-陆壳碰撞
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柴达木北缘都兰野马滩花岗岩锆石SHRIMP定年 被引量:35
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作者 吴才来 杨经绥 +4 位作者 J.L.Wooden 史仁灯 陈松永 A.Meibom C.Mattinson 《科学通报》 EI CAS CSCD 北大核心 2004年第16期1667-1672,共6页
柴北缘超高压带上野马滩花岗岩体位于都兰以北约40 km处, 主要由花岗闪长岩-二长花岗岩-黑云母花岗岩组成, 其中的花岗闪长岩锆石SHRIMP年龄为397 3 Ma. 岩石地球化学研究表明, 该岩体既具有I型花岗岩的部分特征, 又具有S型花岗岩的部... 柴北缘超高压带上野马滩花岗岩体位于都兰以北约40 km处, 主要由花岗闪长岩-二长花岗岩-黑云母花岗岩组成, 其中的花岗闪长岩锆石SHRIMP年龄为397 3 Ma. 岩石地球化学研究表明, 该岩体既具有I型花岗岩的部分特征, 又具有S型花岗岩的部分特征, 类似于碰撞后花岗岩. 结合区域地质特征认为, 该花岗岩是在经历过超高压变质作用的块体最后折返过程中形成的. 展开更多
关键词 野马滩花岗岩 锆石SHRIMP定年 柴北缘超高压带 岩石地球化学 板块构造
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分子化石在寒武—前寒武纪地层中的异常分布及其生物学意义 被引量:40
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作者 张水昌 J.M.Moldowan +5 位作者 Maowen Li 边立曾 张宝民 王飞宇 何忠华 王大锐 《中国科学(D辑)》 CSCD 北大核心 2001年第4期299-304,共6页
甲藻甾烷、4-甲基甾烷、24-降胆甾烷及C28甾烷等常被作为沟鞭藻和硅藻的生 物标志,所以它们在中生代以来的地层中常常具有很高的浓度.然而,这些公认具有特 殊结构和局限生源的化合物却在塔里木盆地寒武系和震旦系含较高有机... 甲藻甾烷、4-甲基甾烷、24-降胆甾烷及C28甾烷等常被作为沟鞭藻和硅藻的生 物标志,所以它们在中生代以来的地层中常常具有很高的浓度.然而,这些公认具有特 殊结构和局限生源的化合物却在塔里木盆地寒武系和震旦系含较高有机质丰度的岩石 抽提物中普遍存在,且具有异常高的浓度.这种结果意味着某些浮游藻如沟鞭藻和硅 藻可能具有更古老的前驱种属,在塔里木盆地和4井及肖尔布拉克剖面寒武系地层中 观察到的一些异常的藻化石,为这种推测提供了可能的生物学证据. 展开更多
关键词 甲藻甾烷 三芳甲藻甾烷 24-降胆甾烷 沟鞭藻 硅藻 寒武纪 塔里木盆地 分子化石 地层分布
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东营凹陷生物降解稠油甾烷分子的选择蚀变 被引量:11
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作者 陈中红 Moldowan J M 刘昭茜 《地球科学进展》 CAS CSCD 北大核心 2012年第10期1108-1114,共7页
为分析生物降解原油中甾烷生物标志物分子发生选择性蚀变的先后顺序及生物降解作用对甾烷分子成熟度参数的影响,在渤海湾盆地东营凹陷广饶潜山油藏选择了发生不同程度生物降解作用的原油,利用色谱质谱(GC-MS)仪对其中甾烷进行了定量测... 为分析生物降解原油中甾烷生物标志物分子发生选择性蚀变的先后顺序及生物降解作用对甾烷分子成熟度参数的影响,在渤海湾盆地东营凹陷广饶潜山油藏选择了发生不同程度生物降解作用的原油,利用色谱质谱(GC-MS)仪对其中甾烷进行了定量测试分析和对比。结果发现在生物降解过程中,不同级别的生物降解作用对甾烷具有不同程度的影响:6级以下的生物降解作用对甾烷的降解能力有限,甾烷及其相关化合物比值没有可以识别的改变;6级以上的严重生物降解作用会对甾烷生物标志物的相关参数产生显著的影响。在严重生物降解原油中(级别≥6):甾烷系列被降解和蚀耗的先后顺序为,ααα20R>αββ20R>αββ20S≥ααα20S,C27>C29>C28,规则甾烷优先于重排甾烷发生降解,C27,C28,C29甾烷优先于C20,C21甾烷发生降解;甾烷生物标志物分子参数C2920S/(20S+20R),C29ββ/(ββ+αα)会发生显著升高,不能真实反映成熟度大小。研究结果为正确评价生物降解原油的成熟度及甾烷生物标志物分子的选择性蚀变提供了新的科学依据。 展开更多
关键词 生物降解作用 甾烷 生物标志物 成熟度参数 东营凹陷
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