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781.
1IntroductionRemotesensinghasbeen1'idelyusedinenvironmentalinveshgahonandmonitoring.Thecharacteristicsofremotesensing,suchaslarge-scale.simultalleous,mulh-form,mulh-specialandmulti-resoluhon.makeitmuchbettertilantileordjnalymedlods,andlakeanimpoftalltroleincoastalwaterqualitymonitoringl'1,includingremotesensingofchlorophyll,suspendedsediment,oilpollution,etc.AJnongwhichsuspendedsedimentremotesensingisanimportalltduct,whichhasbeenresearchedbymanyscientists.andmanytheorehcalandexperimentalmodels… 相似文献
782.
The Holocene Evolution of the Ebre Delta Catalonia, Spain 总被引:2,自引:0,他引:2
1 IntroductionThefirstrelevantinformationaboutthegeologyandevolutionarytrendsoftheEbredeltacameaspartofastratigraphicstudybyMaldonadoA[1].Hementionedthatduringthelasttransgressiveevent,thatisbeforesealevelreacheditspresentlevel,deltaicprogradationonl… 相似文献
783.
Scott Lamoureaux 《Journal of Paleolimnology》1999,21(1):73-84
Multiple cores taken throughout Nicolay Lake in the Canadian High Arctic contain laminated sediments that are interpreted as varved. Annual sediment accumulation during the last 197 years reveals three major patterns that have important implications for hydroclimatic reconstruction. Widespread sediment dispersal is evident during most years and contrasts with years when anomalous localized and bifurcating patterns of deposition occur. Localized deposition is limited to the centre of the lake and is attributed to turbidity currents that originate on the delta foreslope. In contrast, a bifurcating pattern is produced when the river supplying the delta switches from one to two delta distributaries, resulting in altered proximal accumulation. Principal component analysis reveals additional accumulation anomalies that are sedimentologically indistinct, but constitute important sources of localized variance. The recognition and removal of anomalous deposition patterns is critical for accurate reconstruction of sediment flux from the catchment, particularly in long records where geomorphic conditions may have changed. This study identifies potentially misleading depositional artifacts and a methodology to recognize similar depositional controls in other lakes. 相似文献
784.
The Crevillente Fault Zone (CFZ) comprises a system of northeast to southwest oriented dextral faults that extend for some 600 km in the External Zones of the Betic Cordillera (SE Spain). The magnitude of lateral displacement related to this fault zone is not well constrained, and it is considered to be between 20 and 400 km. The stratigraphical and sedimentological criteria used in this work have proven effective in quantifying the magnitude of the displacement along this structure. We have analysed an oolitic turbidite facies in the Middle Jurassic of the Sierra de Ricote (Median Subbetic of Murcia Province). A detailed revision of ooidal limestone outcrops has revealed that the source area of these deposits was to the Internal Subbetic zone, north of Vélez Rubio (Almería Province). These two tectonic units, the Median and Internal Subbetic, are currently 75 km from each other and separated by the CFZ. The conclusions arising from our stratigraphical, petrological and sedimentological studies favour interpretation of a 75–100 km lateral displacement. After restoring the Late Jurassic–Cretaceous anticlockwise rotation of Iberia, the CFZ appears to belong to the E–W palaeofault system that is related to the extension of the South Iberian Continental Margin (SICM). Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
785.
顺序扫描ICP—AES法测定海洋沉积物中九种主要成分 总被引:2,自引:0,他引:2
用ICP—AES法测定海洋沉积物中铝、铁、钙、镁、钠、钾、钦、锰、磷等九种主要成分,方法简便,省时省力,测量精密度小于4%,可以满足海洋地球化学的要求。 相似文献
786.
岬湾相间的琼州海峡南岸在海岸动力条件作用下,岸滩发生侵蚀或堆积,特别是南岸中部的南渡江三角洲沿岸岸滩演变剧烈。该文从海岸动力地貌的角度,对琼州海峡南岸的海岸动力特征、泥沙运动以及岸滩演变进行分析。根据海峡南部三维潮流场数值模拟结果,结合经验公式初步分析潮流引起的泥沙运移速率和方向,得到岸外水域总的泥沙运移趋势为从西向东。根据波浪动力计算分析沿岸泥沙运移,探讨沙质岸滩的动态与地貌演变之间的关系,得出海峡南岸海岸地貌演变与盛行的NE和NNE向风浪有密切关系,岸滩的演变过程主要受制于这两个方向的风浪及其引起的泥沙沿岸运移。 相似文献
787.
788.
789.
海底沉积物孔隙度与声速的关系 总被引:25,自引:10,他引:15
给出大陆架海底沉积层中声速(压缩波)Vp依赖于沉积物孔隙度n的一个新的经验公式,该公式当n=100时,Vp=V0,V0为海底水声速.公式的计算值与我国周边大陆架测量值吻合较好,并将其结果与国内外成果作了对比讨论. 相似文献
790.
In this paper the characteristics of tidal flow and seasonal variation of seidment content in theHangzhou Bay and their affecting factors are studied.Field investigations and data analysis indicate thatthe sediment movement is mainly influenced by the Yangtze estuary and the sediment of the Yangtze estua-ry is induced by wind wave and tidal flow.Owing to the variation of dynamic conditions,the instanta-neous sediment content is controlled by tidal flow,wind wave,depth of water and tidal range synthetically.A sediment content relationship formula is established with related factors.A non-equilibrium2-dimensional numerical model of suspended sediment transportation is set up,and the finite element meth-od is applied.The computation results of the model is in accordance with field data. 相似文献