中国非常规油气沉积学新进展     

邹才能  邱振 《沉积学报》2021,39(1):1-9

经过近20年不断探索,中国陆上非常规油气勘探开发取得了重大进展。2019年全国非常规油气产量占油气总产量的23%,2020年非常规油气产量接近7 000万吨油当量,标志着中国进入非常规油气革命发展新阶段。非常规油气沉积学作为非常规油气地质学理论体系的重要组成部分之一,受到越来越多的关注和重视,形成了“陆相深水砂质碎屑流等重力流沉积模式”、“海陆相富有机质页岩沉积模式”、“细粒沉积岩发育微纳米级孔喉系统”、“多地质事件沉积耦合形成非常规油气甜点区（段）”等重要认识。专辑主要是由从事非常规油气相关的沉积学专家对中国近几年非常规油气层系沉积研究新进展的系统性和及时性总结,内容涵盖了鄂尔多斯、四川、松辽、渤海湾、准噶尔等近50个大中型及中小型含油气盆地,地层时代跨度自元古代至新生代,涉及致密油/页岩油、页岩气、致密气、煤层气、油页岩油等非常规油气层系（段）近30个。这些研究成果为我国非常规油气资源勘探开发提供了重要理论基础与技术支撑。提出未来非常规油气沉积学需以非常规油气工业开发的“甜点箱体”和“甜点群”为重点研究方向,指导非常规油气资源高效勘探开发。  相似文献   

西秦岭造山带泥盆纪沉积地质学和动力沉积学:造山带沉积地质学研究的思想、内容与方法          下载免费PDF全文

杜远生 《沉积与特提斯地质》1995,(3):53-61

造山带沉积地质学是融造山带地层学、沉积学、大地构造学及地球物理、地球化学等为一体的综合性分支学科，被誉为近年来自层序地层学诞生之后，沉积学领域又一次Ｂｅｎｃｈｍａｒｋ式的跃进．本文着重介绍了造山带沉积地质学研究中应坚持以活动论思想为指导，借鉴沉积盆地分析中整体分析、综合分析、背景分析和演化分析的学术思想和工作原理，并结合造山带结构和盆地及古海洋格局，确定造山带沉积地质学研究内容和技术路线、造山带沉积地质学包括造山带区域地层学、区域沉积学、区域构造学、地层层序和沉积演化、古地理和古海洋格局、动力沉积学和动力演化模式等内容和多层次综合研究的技术路线。  相似文献   

A multivariate sedimentary environmental analysis of Great South Bay and South Oyster Bay, New York     

Syed A. Ali  Richard H. Lindemann  Peter H. Feldhausen 《Mathematical Geology》1976,8(3):283-304

A multivariate statistical strategy for classifying paleoenvironments is effective for studying modern sedimentary processes in western Great South Bay and South Oyster Bay, New York. The 13 whole phi weight percent variables were tested for redundancy with R-mode cluster analysis. The samples were partitioned statistically into five environmentally significant facies using Q-mode cluster analysis: (A)sandy gravel, (B)sandy silt, (C)silty sand, (D)slightly gravelly sand, and (E)fine sand. An ordination depicted gradational relationships among the samples and the facies. It was used to evaluate the environmental and textural parameter gradients within the sample space. Interpretations obtained in this manner and by examination of the grain-size curves suggest that these sediments were deposited by waves and currents on beaches and in wave zones (facies C and E),shoal areas (facies B),and tidal channels (facies A and D).Tidal currents, wave action, and eelgrass control the distribution of sediments within the two bays.  相似文献   

Depositional controls on Palaeoproterozoic iron formation accumulation, Gogebic Range, Lake Superior region, USA     

Peir K. Pufahl  Philip W. Fralick 《Sedimentology》2004,51(4):791-808

Shallowing‐upward, decametre‐scale, Palaeoproterozoic iron formation cycles in northern Wisconsin record the combined effects of tectonism and changing oceanographic conditions on a storm‐dominated shelf. Cycles consist of a lower unit of laminated, Fe‐ and Si‐rich chemical mudstone that is transitional into an upper unit dominated by trough cross‐stratified chert grainstone. Grainstone lenses become progressively thicker upwards in cycles with the largest at cycle tops, where they are sharply overlain by a unit of slumped chemical mudstone. The cycles developed through progradation when offshore‐directed storm currents transported chert sand intraclasts that were formed in nearshore settings into middle and distal shelf environments. Abrupt subsidence events, probably resulting from normal faulting associated with extensional tectonism, repeatedly terminated chert grainstone accumulation and may also have generated the slumped units at cycle boundaries. The episodic storm currents are also interpreted to have transported biologically oxygenated waters from the shallow‐water, inner shelf into otherwise anoxic bottom waters of the strongly stratified distal shelf. The consequence of such transport and mixing was rapid deposition of chemical mud, mainly as precipitated Fe‐oxide. In many cases, the resultant decrease in Fe²⁺ in the water column, together with pelagic inorganic precipitation of SiO₂ and rainout of terrigenous clays, resulted in submillimetre‐ to millimetre‐thick, chemically graded laminae. The concomitant decreasing Fe²⁺/Mn²⁺ ratio also led to increasing Mn‐compound precipitation and enrichment in the upper portions of some chemically graded layers.  相似文献   

A distribution‐free statistical method for the spatial characterization of dune granulometry: an example from the Strzelecki Desert,South Australia     

Mark A. Bishop 《地球表面变化过程与地形》2004,29(1):125-131

Distribution‐free statistical methods of comparative data analysis have identi?ed subtle granulometric differences attributed to the evolution of barchan form at Gurra‐Gurra waterhole. Geomorphic locations on the barchan dunes display statistically signi?cant grain‐size differences that assist in the interpretation of aeolian processes. In summer, very ?ne sands mantle the dunescape and are the fraction that most affects the parameters of sorting and skewness. The sur?cial sedimentological character is one of subtle contrasts between the processes of grain winnowing and intergranular protection. The second and third moment measures are parameters that best demonstrate the spatial granulometric differences. Dune‐forming processes at Gurra‐Gurra have produced dune sands that have a very narrow range of grain size, which, in turn, re?ects textural and mineralogical maturity, and hence an extensive transport history. The statistical techniques employed in this study can also be used for the comparison of temporal (seasonal) sedimentological change, and for the granulometric analysis and association of process for dunes of different morpho‐types. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

Climatic control on Quaternary fluvial sedimentology of a Fenland Basin river, England   总被引：1，自引：0，他引：1  

REBECCA M. BRIANT  MARK D. BATEMAN†  G. RUSSELL COOPE‡  PHILIP L. GIBBARD 《Sedimentology》2005,52(6):1397-1423

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Magnitude and frequency in proglacial rivers: a geomorphological and sedimentological perspective     

Philip M.   《Earth》2005,70(3-4):203-251

Proglacial fluvial sedimentary systems receive water from a variety of sources and have variable discharges with a range of magnitudes and frequencies. Little attention has been paid to how these various magnitude and frequency regimes interact to produce a distinctive sedimentary record in modern and ancient proglacial environments. This paper reviews the concept of magnitude and frequency in relation to proglacial fluvial systems from a geomorphic and sedimentary perspective rather than a hydrological or statistical perspective. The nature of the meltwater inputs can be characterised as low-magnitude–high-frequency, primarily controlled by ablation inputs from the source glacier, or high-magnitude–low-frequency, primarily controlled by ‘exceptional’ inputs. The most important high-magnitude–low-frequency inputs are catastrophic outburst floods, often referred to by the term jökulhlaup (Icelandic for glacier-burst). Glacier surges are an additional form of cyclical variation impacting the proglacial environment, which briefly alter the volumes and patterns of meltwater input. The sedimentary consequences of low-magnitude–high-frequency discharges are related to frequent variations in stage, the greater directional variability that sediment will record, and the increased significance of channel confluence sedimentation. In contrast, the most significant characteristics of high-magnitude–low-frequency flooding include the presence of large flood bars and mid-channel ‘jökulhlaup’ bars, hyperconcentrated flows, large gravel dunes, and the formation of ice-block kettle hole structures and rip-up clasts. Glacier surges result in a redistribution of low-magnitude–high-frequency processes and products across the glacier margin, and small floods may occur at the surge termination. Criteria for distinguishing magnitude and frequency regimes in the proglacial environment are identified based on these major characteristics. Studies of Quaternary proglacial fluvial sediments are used to determine how the interaction of the various magnitude and frequency regimes might produce a distinctive sedimentary record. Consideration of sandur architecture and stratigraphy shows that the main controls on the sedimentary record of proglacial regions are the discharge magnitude and frequency regime, sediment supply, the pattern of glacier advance or retreat, and proglacial topography. A model of sandur development is suggested, which shows how discharge magnitude and frequency, in combination with sandur incision and aggradation (controlled by glacier advance and retreat) can control sandur stratigraphy.  相似文献   

长--平陆相红色盆地北东段量化沉积学特征及其演化   总被引：1，自引：0，他引：1  

章泽军 《沉积学报》1998,16(4):55-61

长－平陆相红色盆地北东段（系指赣西北红层分布区）由三期5个冲积扇体组成。非同期扇体分别由特定界面所分隔。山口位于盆地北侧,古流向由北向南、南东或南西呈扇形撒开;最大砾石平均体积及混杂系数在扇根处为最大值,向扇中、扇缘呈非线性递减;砾石成分严格受物源区的制约。根据量化沉积学特征及成生背景分析,该区大致经历了初始孕育期、分段剥蚀充填期及后期构造改造三大演化阶段。洪积事件始于晚白垩世、止于早第三纪始新世-渐新世。  相似文献   

关于造山带动力沉积学若干问题的思考     

杜远生 《地学前缘》1998,(Z1)

造山带动力沉积学是造山带地质学和大陆动力学研究的重要方面。造山带动力沉积学研究的重要基础是识别造山带的原型沉积盆地,认识其大地构造沉积相和原型沉积盆地的演化。造山带动力沉积学研究的主要内容包括造山带区域地层学、沉积学、大地构造学、造山带原型盆地的充填序列或构造层序、古地理和古海洋及建立沉积盆地的动力模式。其研究方法涉及造山带原型盆地的物源和组分分析、沉积相和沉积体系及沉积构型分析、充填序列和构造层序分析、古流向和古地理分析、沉积厚度和沉降分析以及沉积盆地动力模拟等。  相似文献   

Paleolimnology of the McMurdo Dry Valleys,Antarctica   总被引：1，自引：0，他引：1  

Peter T. Doran  Robert A. Wharton Jr.  W. Berry Lyons 《Journal of Paleolimnology》1994,10(2):85-114

The McMurdo Dry Valleys presently contain more than 20 permanent lakes and ponds, which vary markedly in character. All, with the exception of a hypersaline pond, have a perennial ice-cover. The dry valley lakes, and lakes in other ice-free regions of continental Antarctica, are unique on this planet in that they consistently maintain a thick year-round ice cover (2.8–6.0 m) over liquid water. The persistent ice covers minimize wind-generated currents and reduce light penetration, as well as restricting sediment deposition into a lake and the exchange of atmospheric gases between the water column and the atmosphere. From a paleolimnological perspective, the dry valley lakes offer an important record of catchment and environmental changes. These lakes are also modern-day equivalents of periglacial lakes that were common during glacial periods at temperature latitudes. The present lakes are mostly remnants of larger glacial lakes that occupied the valleys in the past, perhaps up to 4.6 Ma ago. Two of the valleys contain evidence of being filled with large glacial lakes within the last 10000 years. Repeated drying and filling events since then have left a characteristic impression on the salt profiles of some lakes creating a unique paleo-indicator within the water column. These events are also marked in the sediments by the concentration and dilution of certain chemical constituents, particularly salts, and are also corroborated by carbonate speciation and oxygen isotope analysis. Stratigraphic analysis of dry valley lake sediments is made difficult by the occurrence of an old carbon reservoir creating spurious radiocarbon dates, and by the high degree of spatial variability in lake sedimentation. From a biological perspective, the lakes are relatively simple, containing various taxa of planktonic and benthic microorganisms, but no higher forms of life, which is an advantage to paleolimnologists because there is no bioturbation in the sediments. Useful biological paleo-indicators found in the sediments include cyanobacterial filament sheaths, diatom frustules and other eukaryotic algal cells, protozoan cysts, photosynthetic pigments, and minerals (e.g. carbonates) associated with microbial activity. Future work will benefit from fully characterizing the connection between the ice covers, environmental conditions, and paleo-indicators, thereby allowing refinement of inferences made concerning the paleoenvironment. New dating techniques need to be tested in this environment to overcome the problems associated with radiocarbon dating. The establishment of a detailed and focused paleolimnological campaign is proposed.  相似文献