简介：Anumberofphenomenaandprocessesingeosciencescanbesummarizedbysecondorderpartialdifferentialequations.Themajornumericalmethodsfortheirsolutionincludetheclassicalfinitedifferencemethodandthefiniteelementmethodnewlydevelopedinthelasttwoorthreedecades.Since1977theauthorhasprovedthatfortheLaplaceandPoissonequations,thesetwomethodsareidenticalandaredifferentonlyintheprocessofformulation.Fortransientproblems,suchasheatconductionintheearthandthegroundwaterandoil-gasunsteadyflowinporousmedia,therearesomedifferencesinresultinglinearalgebraiceuqations.Ingeneral,twomethodsgivesimilarresults,butwhenthetimestepisdecreasedtosomeextent,theresultingalgebraicequationwillbeconsistentwiththeanti-heatconductionequationratherthantheoriginalheatconductionequation.Thisisthereasonwhyunrealisticpotentialsareproducedbythefiniteelementmethod.Suchaproblemcanbeovercomebyusingthe

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简介：ThevegetationhasbeenpoisonedbygoldinthewesternGuangdong-Hainanregion.Thegoldcontentoftheleavesthereisashighas10-1961timestheabundance,thechlorophyllcontentis10%-30%lowerthanthatofthevegetationinmetamorphicterrainsand10%-20%higherthanthatingraniteterrains,andthecarotenoidcontentis10%-44%lowerthanthebackgroundvalue.Thewatercontentofleavesis10%to20%lowerthanthebackgroundvalue.Thecellsofleavesaredeformedandbroken.Theleafsurfaceshowscolourspotsandbecomesyellowordarkgreen.Thespectralreflectanceoftheleafsurfaceis5%-30%higherthanthebackgroundvalue:thespectralshapehasshifted5-15nmtotheshortwavelength.ThegrayscalesofeanopyonimagesofLandsatTMandairborneimagingscanner(AIS)are10%-100%higherthanthebackgroundvalues.OnLandsatTMandAISfalsecolourimages,plantspoisonedbygolddisplayayellowcolor,whichdisinguishesthemfrombackgroundplants.Accordingtothespectralandimagefeaturesofgoldbiogeochemicaleffects,theauthorhasconstructedagoldinformationsystemandexpertpredictionsystem,andthustwogoldtargetareasandtwogoldprospectareashavebeenidentifiedrapidly,economicallyandaccuratelyinthewesternGuangdong-Hainanregionwhichisextensivelycoveredbyvegetation.

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简介：Offshoredrillingandproductionoperationscanresultinspillsorleaksofhydrocarbonsintoseabedsediments,whichcanpotentiallycontaminatethesesedimentswithoil.Ifthisoillatermigratestothewatersurfaceithasthepotentialfornegativeenvironmentalimpacts.Forpropercontingencyplanningandtoavoidlargerconsequencesintheenvironment,itisessentialtounderstandmechanismsandratesforhydrocarbonmigrationfromoilcontainingsedimentstothewatersurfaceaswellashowmuchwillremaintrappedinthesediments.Itisbelievedthattheamountofoiltransportedoutofthesedimentcanbeaffectedbytidalpumping,acommonformofsubterraneangroundwaterdischarge(SGD).However,wecouldfindnostudyexperimentallyinvestigatingthephenomenonoffluidflowinsubseasedimentscontainingoilandtheeffectsoftidalpumping.Thisstudypresentsanexperimentalinvestigationoftidalpumpingtodetermineifitisapossiblemechanismthatmaycontributetotheappearanceofanoilsheenontheoceansurfaceaboveasedimentbedcontainingoil.AnexperimentalapparatuswasconstructedofclearPVCpipeallowingforoilmigrationtobemonitoredasitflowedoutofasandpackcontainingoil,whiletidalpressureoscillationswereappliedinthreedifferentmanners.Theeffectoftidalpumpingwassimulatedviacompressionofairabovethewater(whichsimulatedtheincreasingstaticheadfromtidalexchange).Experimentalresultsshowthatsustainedoilreleaseoccurredfromalltests,andtestswithoscillatingpressureproducedforlongerperiodsoftime.Furthermore,theexperimentalresultsshowedthattheoilmigrationratewasaffectedbygrainsize,oilsaturation,andoscillationwavetype.Inalloscillatingexperimentstherateandultimaterecoverywaslessthanthecomparablestaticexperiments.Fortheconditionsstudied,theexperimentalresultsindicatethatwithanoscillatingpressureontopofasandpack,movementofanon-replenishingsourceofoilissuppressed

简介：BasedonPb-Pbisochrondataofmorethan40Precambrianpolymetallicdeposits,theauthorsconsiderthattherearefourmineralizationperiodsforthePrecambriancopperdepositsinChina,andthemajorcopperdepositswereformedatabout1800Ma;therearethreemineralizationperiodsforgolddepositsformedfromArchaeantoProterozoic.BystudyinghundredsofleadisotopedatafromsomeMesozoiccontinentalsubvolcanicCuandAgpolymetallicdepositsandfine-disseminatedgolddeposits,theauthorsfoundthatthecalculationbasedontheleadsingle-stageevolutionmodelortwo-stageevolutionmodelcannotgivethetrueore-formingagesbutcanprovidemoreinformationaboutmineralizationandmaterialsourcesofthedeposits.

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简介：1IntroductionTheweatheredcrustrareearthdepositsisoneofthemostsignificantrareearthdeposits,whicharemostlydistributedinsouthernChina,especiallyinthesouthofJiangxiprovince(Chietal.,2007).Thecompositionsofthesedeposits,whichareweatheredfromigneousrockssuchasgranitethroughbiological,physicalorchemical

简介：Thesuper-largePb-ZndepositatFankouisverycomplexinmetallogenicmechanism.Syngeneticbrinesedimentation,hotsubmarinespringeruption-accumulation,syngeneticsedimentation-vadosebrinereplacementhadbeensupposedasthegeneticmodelsbefore.Underthesemodels,syngeneticmineralizationshouldbedominantinoreformation.However,aseriesofgeologicalandgeochemicalpropertiesinvestigatedbyauthorsofthispaperarecontrarytothesemodels.Therefore,theauthorsheresuggestthatthisdepositisatypicalpolygeneticcompoundoredepositwhichsharethepropertiesofmultistagesofgeotectonicevolution,multifactorsofmineralizationcontrol,multisystemofmaterialderivationofmineralization,multimodesofmineralizationandmultitypesofgenesis.

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简介：TheMayangCudeposit,westernHunanisamiddle-scalesandstone-typeCudepositpredominantofnativecopper.Fromanangleofgeologicalintegrativefield,fracturegeochemicalfeaturesarestudidedanddiscussedinthispaper.Infracturestructure,variantregularityandtheratiosofelementcouplesparticipatinginmetallogensisthattheirgeochemicalnaturesaresimilarorstronglycorrelative,revealchanginglawsofmetallogenictemperatureandpressurefieldsandmigratingdirectionofmetallogenicelements.Thetheoreticalstudytalliesmuchbetterwithproductivepractice.Theyaremeaningfultoconductprospectingandexployation.

简介：ThegeologicalfeaturesoftheLongshanAu-Sbdepositsaresystematicallydescribed.Mineralizationconditions,sourcesoforematerialsandmetallogeneticmechanismarealsoanalysedaccordingtosulfur,oxygenisotopecomposition,pyritetypomorphicfeaturesandfluidinclusionthermometrydating,Theresultsshowthatitisasedimentarymetamophichydrothermaldeposit.

简介：TheLamasucopperpolymetallicmineralizedregionliesinthesouthofWenquanCounty,XinjiangandintheNorthwestlakesideoftheSailimuLake.Seenfromthegeotectonicposition,itbelongstoNorthTianshangeodomesystem,Tianshandiwaregion,CentralAsiancrustobody.Copperandzincpolymetallicorebodieshadbeenformedintheskarnofthecontact,betweenthemetamophiccarbonaterocksoftheKuximqiekGroup,JixianSystemandearlymid-Variseanacidicrockbodies.Theformationoftheoredepositwastheresultofthesuccessiveactivitiesofthecrustandmantleandthetectonicandmagmaticactivities.

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简介：沿着陡峭的斜坡的分开的岩石块的下坡的运动是沿着一个斜坡并且在山谷底部上的脚危及基础结构的安全的一个重要过程，但是仅仅有限的知识在对如此的块的运动的速度和距离的各种各样的因素的影响上是可得到的。我们在斜坡上讨论团的影响和岩石块，斜坡的险峻，和overburden的厚度的形状，在岩石的运动的距离上，不同地在256个领域实验被观察与的块与176m的高度在斜坡上从3个不同位置塑造了块。地测试的结果的统计评估证明斜坡坡度调节并且压垂是主要因素，岩石群众的表格是第二个因素，并且团是第三个影响因素。当岩石群众的团是15m时，它是为岩石群众的运动的最大的平均加速<27kg，岩石群众的表格是薄片，坡度的条件是平均59.6潣摮湥慳整?慨楶杮栠杩敨?慰慲晦湩愠摮氠睯牥愠潲慭楴楣祴琠慨?敲楳畤污漠汩s吗？

简介：<正>BrineresourceisrichinChina,butitsexploitationhasbeenaproblem.Hypersalinebrinewillcorrodeequipmentandmaterialsseriouslyduringthebrineexploitationandtransportation.Thecorrosionproblemcancausegreat

简介：ＳｔｕｄｙｏｎＥｏｇｅｎｅＢａｓａｌｔｓ：ＩｍｐｌｉｃａｔｉｏｎｏｆｔｈｅＤｅｅｐＰｒｏｃｅｓｏｖｅｒｔｈｅＢｏｈａｉｗａｎＢａｓｉｎＥｖｏｌｕｔｉｏｎ＊ＹｅＤｅｌｏｎｇＬｕＦｅｎｇｘｉａｎｇＺｈｕＱｉｎｗｅｎＺｈｅｎｇＪｉａｎｐｉｎｇＦａｃｕｌｔｙ...

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简介：Coalisalwaporelatedtoaccumulatingandburialofrcmainsofplantorlowcranimal-plantandmi-croorganism.Thecharacteristicsofmacroscopicandmicrocosmicmaccral,geologicaloccurrence,pctrologyandmineralogyofcoalmcasuresstrata,lithofaCjcsandpaleoSeo8raphy,8eochcmistryandsoonmakeknownthatcoalisanexogeneticsedimenta