長江口北支興隆沙沉積環(huán)境分析.pdf

1、華東師范大學碩士學位論文長江口北支興隆沙沉積環(huán)境分析姓名：周開勝申請學位級別：碩士專業(yè)：環(huán)境科學指導教師：洪雪晴20050401華東師范大學2005屆碩士學位論文AbstractAbstractTheresearchaboutcoreXLl、XL2andsectionSTGonXinglongSandintheNorthBranchofChangjiangestuaryhavemainlybeenfocusedonthemodernag

2、gradationandanalyzingthesedimentprocessofNorthBranchofChan百iangestuarythroughthehydrodynamiccondition，whileresearchworksonthesedimentaryenvironmentAftermanysamplingintheprofileoftheXLl、XL2CoreandSTGsection，Ihavedonethepa

3、rticleanalysis，theenvironmentmagneticanalysisandthemacrofossilanalysisThenthemainresultsCanbeconcludedthroughtheabovementionedanalysis1ThegrainsizecompositionofXinglongsandismainlyfineandcoarsesand，whichreflectsthehydrod

4、ynamicconditionisstrongerTheparticleparametersandthecBrvgsofthetypicalsamples’demonstratethechangeofthesUongerandweakerhydrodynamicconditionindifferentdepthTherhythmofthegrainsizechangealongthedepthisdistinctness，anditin

5、dicatesthehydrodynamicchangetakeonobviouspulsatiletrait。2ThelowervalueofxSlRMshowsthecontentofmagneticgrainsintheXinglongsandisverylittleThevarietyofS100％between719and891andthevarietyofBcrbetween63and302，alongwithF300％pr

6、eponderatesover90％，asindicatestheferrousmagneticmineraldominatingmagneticpropertiesThelowervalueofxarm／x、z／SlRMandzfd％showsthatthepseudosingledomain(PSD)andmultidomain(MD)dominatetheparticleofthemagneticmineral，andthatth

7、eSuperparamagnetism(SP)isless，whichalsoindirectlyreflectsthehydrodynamicconditionisstronger3ThenumberofforaminifemisrathermoreThemostarebetweenseveralhundredsandthousands，thesizeoftheforaminiferaissmallerthespeciesarefew

8、Enaraensis，A，convexidorsa，Abeccariivatsetcdominatingthebenthicferminifera，theplankforaminiferaisalsodistributinginChangjiangestuary，Thedistributingfeatureofforaminiferaindicatingthatsalinitycontrolstheforaminifera’sdistr

9、ibution4Basedoncomprehensiveanalysisofthecontentvariationofgrainsize，themagneticanalysis，theforaminiferaanalysisandotheranalysis，itcanbefoundthatthemodeofenvironmentalevolvementoftheXinglongsand：tidalchannel—tidalcurrent