Beryllium-10 terrestrial cosmogenic nuclide surface exposure dating of Quaternary landforms in Death Valley     

Lewis A. Owen  Kurt L. Frankel  Jeffrey R. Knott  Scott Reynhout  Robert C. Finkel  James F. Dolan  Jeffrey Lee 《Geomorphology》2011,125(4):49

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Mixed sand–mud bedforms produced by transient turbulent flows in the fringe of submarine fans: Indicators of flow transformation     

Megan L. Baker  Jaco H. Baas 《Sedimentology》2020,67(5):2645-2671

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Facies analysis of the Middle and Late Quaternary sediment infill of the northern Weihe Basin,Central China          下载免费PDF全文

Daniël S. Rits  Maarten A. Prins  Simon R. Troelstra  Ronald T. van Balen  Yan Zheng  Christiaan J. Beets  Bin Wang  Xiaoqiang Li  Jie Zhou  Hongbo Zheng 《第四纪科学杂志》2016,31(2):152-165

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Comments on ‘Hybrid sediment gravity flows – classification,origin and significance’ from Haughton,Davis, McCaffrey and Barker (Marine and Petroleum Geology, 2009, 26, 1900–1918)     

Roger Higgs 《Marine and Petroleum Geology》2010

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塔里木盆地北部白垩系-古近系不同段、带沉积体系比较研究     

朱如凯  高志勇  郭宏莉  韩丹  张丽娟  孙玉善  程明 《沉积学报》2007,25(3):325-331

塔里木盆地北部库车坳陷—塔北地区白垩系—古近系发育有冲（洪）积扇、终端扇、三角洲（扇三角洲、辫状河三角洲、正常三角洲）、湖泊、滨岸海滩、潮坪—潟湖等多种沉积相类型。研究区南、北带及东、中、西段在不同沉积演化时期发育的岩性组合、沉积相类型及沉积相平面展布规模方面也有明显差异,北带主体为粗碎屑沉积,发育扇三角洲沉积;南带沉积物粒级相对较细,主体发育辫状河三角洲,这种差异主要受当时古构造位置、古地形坡度、沉积物源远近及古气候控制。  相似文献   

Fast static correction methods for high-frequency multichannel marine seismic reflection data: A high-resolution seismic study of channel-levee systems on the Bengal Fan     

Martin Gutowski  Monika Breitzke  Volkhard Spieß 《Marine Geophysical Researches》2002,23(1):57-75

Very high-frequency marine multichannel seismic reflection data generated by small-volume air- or waterguns allow detailed, high-resolution studies of sedimentary structures of the order of one to few metres wavelength. The high-frequency content, however, requires (1) a very exact knowledge of the source and receiver positions, and (2) the development of data processing methods which take this exact geometry into account. Static corrections are crucial for the quality of very high-frequency stacked data because static shifts caused by variations of the source and streamer depths are of the order of half to one dominant wavelength, so that they can lead to destructive interference during stacking of CDP sorted traces. As common surface-consistent residual static correction methods developed for land seismic data require fixed shot and receiver locations two simple and fast techniques have been developed for marine seismic data with moving sources and receivers to correct such static shifts. The first method – called CDP static correction method – is based on a simultaneous recording of Parasound sediment echosounder and multichannel seismic reflection data. It compares the depth information derived from the first arrivals of both data sets to calculate static correction time shifts for each seismic channel relative to the Parasound water depths. The second method – called average static correction method – utilises the fact that the streamer depth is mainly controlled by bird units, which keep the streamer in a predefined depth at certain increments but do not prevent the streamer from being slightly buoyant in-between. In case of calm weather conditions these streamer bendings mainly contribute to the overall static time shifts, whereas depth variations of the source are negligible. Hence, mean static correction time shifts are calculated for each channel by averaging the depth values determined at each geophone group position for several subsequent shots. Application of both methods to data of a high-resolution seismic survey of channel-levee systems on the Bengal Fan shows that the quality of the stacked section can be improved significantly compared to stacking results achieved without preceding static corrections. The optimised records show sedimentary features in great detail, that are not visible without static corrections. Limitations only result from the sea floor topography. The CDP static correction method generally provides more coherent reflections than the average static correction method but can only be applied in areas with rather flat sea floor, where no diffraction hyperbolae occur. In contrast, the average static correction method can also be used in regions with rough morphology, but the coherency of reflections is slightly reduced compared to the results of the CDP static correction method.  相似文献   

Physical sedimentology experiments with sulfuric acid solutions: Implications for Mars?     

Kathleen C. Benison  Deidre LaClair  Jessica Walker   《Earth and Planetary Science Letters》2008,270(3-4):330-337

Physical sedimentology experiments have shown that sulfuric acid solutions may have formed some surface features seen on Mars. Recent data returned from Mars show the presence of jarosite, sulfate salts, hematite, phyllosilicates, and opaline silica, all of which precipitate from some terrestrial sulfuric acid solutions. There is a plethora of geochemical, mineralogical, and sedimentological data indicative of past sulfuric acid systems on Mars, but there has never been a comprehensive study published regarding sulfuric acid as a physical sedimentological agent. In the laboratory, we ran liquids of various compositions over sediments in order to test how these liquids entrain, transport, and deposit sediments. Pure water and concentrated sulfuric acid solutions produced the same general features, such as channels, gullies, and alluvial fans. However, sulfuric acid solutions yielded some distinct sedimentary features not produced by pure water runs. These features, narrow, deeply incised channels of consistent widths, rounded discrete fans, and air bubble “craters”, are similar to some Martian landscape features. These experimental results indicate that acid solutions should be considered a possible sedimentological agent on Mars.  相似文献   

Late glacial fans in the eastern Skagerrak; depositional environment interpreted from swath bathymetry and seismostratigraphy     

Oddvar Longva  Heidi A. Olsen  David J.W. Piper  Leif Rise  Terje Thorsnes 《Marine Geology》2008,251(1-2):110-123

The origin of acoustically transparent fan deposits overlying glacial till and ice-proximal sediments on the southern margin of the Norwegian Channel has been studied using high-resolution seismic-reflection profiles and multibeam bathymetry. The first deposits overlying glacigenic sediments are a series of stacked, acoustically transparent submarine fans. The lack of glaciomarine sediments below and between individual fans indicates that deposition was rapid and immediately followed the break up of the Late Weichselian ice cover. The fans are overlain by stratified glaciomarine sediments and Holocene mud. Because of the uniformity of this drape, the upper surface of the fan deposits is mimicked at the present seafloor, and the bathymetric images clearly show the spatial relationship of the fans to bedrock ridges and the presence of braided channel-levee systems on the surface of the youngest fans. The acoustically transparent character of the fan deposits indicates that they comprise silt and clay, and their lobate form and lack of internal stratification indicates that they were deposited by debris flows. The channel-levee morphology indicates deposition from more watery hyperconcentrated fluid flows. The fan sediments were either derived from 1) erosion of Mid Weichselian lake deposits in southern Skagerrak or 2) from Late glacial ice-margin lake deposits, ponded against the Norwegian Channel ice stream, which collapsed catastrophically when the lateral support was removed as the ice disintegrated. Fans composed almost exclusively of fine-grained sediment need not, therefore, rule out an origin in a deglacial setting relatively close to the former margins of glaciers and ice sheets.  相似文献   

廊固凹陷近岸水下扇特征及控制因素   总被引：2，自引：0，他引：2  

宋荣彩  张哨楠  董树义  周文 《地球科学与环境学报》2007,29(2):145-148,157

通过对廊固凹陷18口井541 m岩心的系统观察、156口井测井序列的建立、1km×1 km三维地震测网密度的地震相识别,分析了该沉积体系的相带展布特征。该砂砾岩层总体趋势为向上厚度减薄、层数减少,共识别出5期扇体,多呈条带状沿大兴断层断面分布,每期之间发育稳定的暗色泥岩段。该近岸水下扇的形成受3级层序、大兴断层、古构造、古气候、古地形以及物源供给等多种因素的控制。3级层序的发育特点、大兴断层的分段活动以及特殊的物源供给背景因素的匹配对近岸水下扇形成起到决定性作用。2~3期扇体扇中分布范围广,储集条件好,是凹陷下一步开发工作的有利目标。  相似文献   

海-塔盆地中部断陷带南屯组沉积体系配置及有利相带分析     

黄薇  吴海波  李军辉  刘赫 《沉积学报》2016,34(1):120-128

本文充分利用岩芯、测井、地震及分析化验等资料,对海-塔盆地中部断陷带4个主力凹陷的南屯组砂体类型及分布特征进行了详细研究。结果表明,南屯组主要发育扇三角洲、近岸水下扇、辫状河三角洲和湖底扇等4种典型类型砂体,并从沉积背景、发育部位、沉积特征、搬运机制以及地震反射特征等5个方面,分不同角度、不同层次详细阐述了扇三角洲、近岸水下扇、辫状河三角洲和湖底扇的识别标志;其中扇三角洲主要分布在乌尔逊凹陷和贝尔凹陷的陡坡带,近岸水下扇主要分布在南贝尔凹陷和塔南凹陷的陡坡带,而辫状河三角洲主要分布乌尔逊凹陷、贝尔凹陷和南贝尔凹陷的缓坡带。从盆地边部向盆地中心方向,沉积相由扇三角洲、近岸水下扇和辫状河三角洲沉积逐渐过渡为半深湖-深湖相沉积,局部半深湖-深湖相中发育湖底扇沉积体系,整体具有“南北分块、东西分带”的沉积格局。综合研究表明,扇三角洲前缘、近岸水下扇中扇和辫状河三角洲前缘砂体是油气富集的有利沉积相带,而洼槽边缘的湖底扇砂体为岩性油气藏勘探的重点对象。  相似文献