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9 个结果
  • 简介:地震小浪评价是地震数据处理和解释的重要部分,谁的正确直接与deconvolution和倒置的结果有关。小浪评价基于高顺序的系列是一个重要新方法。然而,高顺序的系列经常有阶段包装纸问题,它导致小浪阶段光谱偏差并且从而影响混合阶段小浪评价。解决这个问题,我们建议一个新阶段光谱方法基于在bispectral领域的保角的印射。方法避免由缩小Fourier阶段光谱的范围消除在原来的阶段包影响的bispectral阶段包问题的阶段光谱评价。方法基于保角的印射组成最少平方的小浪阶段光谱评价它与最少平方的小浪振幅光谱评价被用于混合阶段小浪评价。理论模型和实际地震数据验证这个方法的有效性。我们也扩大到trispectral小浪阶段光谱评价的在bispectral小浪阶段光谱评价的保角的印射的想法。

  • 标签: 地震子波估计 保角变换 应用 双频 地震波 地震资料处理
  • 简介:在地震小浪振幅光谱精确地被估计的假设上,有不同阶段系列的一组小浪,是估计了小浪考虑了,被用来实现线性最少平方的倒置。在倒置期间,除了小浪阶段,影响倒置结果的所有另外的因素没被考虑。稀少的反射率的倒置结果当模特儿(或短而粗的阻抗模型)显示出那:(1)尽管用倒置结果的合成数据与原来的地震数据匹配很好,转换反射率和声学的阻抗与真正的模型的不同。(2)倒置结果可靠性依赖于估计的小浪Z变换根分发。当估计的小浪Z变换根仅仅在联合起来的圆附近不同于真实小浪的时,转换反射率和阻抗与真正的模型通常一致;(3)尽管合成数据与原来的数据和Cauchy标准匹配很好(或修改Cauchy标准)与一个常数,抑制参数被优化了,转换结果极大地是静止的与真正的模型不同。最后,我们作为评估标准与适应抑制参数用L1标准,峭度,变化,有适应抑制参数的Cauchy标准或/并且修改Cauchy标准建议减少不精密的小浪阶段评价的坏影响并且在理论获得好结果。

  • 标签: 地震反演 相位估计 小波 柯西准则 最小二乘反演 阻尼参数
  • 简介:EstimationofThomsen'sanisotropicparametersisveryimportantforaccuratetime-to-depthconversionanddepthmigrationdataprocessing.Comparedwithothermethods,itismucheasierandmorereliabletoestimateanisotropicparametersthatarerequiredforsurfaceseismicdepthimagingfromverticalseismicprofile(VSP)data,becausethefirstarrivalsofVSPdatacanbepickedwithmuchhigheraccuracy.Inthisstudy,wedevelopedamethodforestimatingThomsen'sP-waveanisotropicparametersinVTImediausingthefirstarrivalsfromwalkawayVSPdata.Modelfirst-arrivaltraveltimesarecalculatedonthebasisofthenear-offsetnormalmoveoutcorrectionvelocityinVTImediaandraytracingusingThomsen'sP-wavevelocityapproximation.Then,theanisotropicparameters0andearedeterminedbyminimizingthedifferencebetweenthecalculatedandobservedtraveltimesforthenearandfaroffsets.Numericalforwardmodeling,usingtheproposedmethodindicatesthaterrorsbetweentheestimatedandmeasuredanisotropicparametersaresmall.Usingfielddatafromaneight-azimuthwalkawayVSPinTarimBasin,weestimatedtheparameters0andeandbuiltananisotropicdepth-velocitymodelforprestackdepthmigrationprocessingofsurface3Dseismicdata.Theresultsshowimprovementinimagingthecarbonatereservoirsandminimizingthedeptherrorsofthegeologicaltargets.

  • 标签: Walkaway VSE Thomsen's ANISOTROPIC parameters VTI
  • 简介:Inheterogeneousnaturalgasreservoirs,gasisgenerallypresentassmallpatch-likepocketsembeddedinthewater-saturatedhostmatrix.Thistypeofheterogeneity,alsocalled"patchysaturation",causessignificantseismicvelocitydispersionandattenuation.Toestablishtherelationbetweenseismicresponseandtypeoffluids,wedesignedarockphysicsmodelforcarbonates.First,weperformedCTscanningandanalysisofthefluiddistributioninthepartiallysaturatedrocks.Then,wepredictedthequantitativerelationbetweenthewaveresponseatdifferentfrequencyrangesandthebasiclithologicalpropertiesandporefluids.Arockphysicstemplatewasconstructedbasedonthinsectionanalysisofporestructuresandseismicinversion.ThisapproachwasappliedtothelimestonegasreservoirsoftherightbankblockoftheAmuDaryaRiver.Basedonpoststackwaveimpedanceandprestackelasticparameterinversions,theseismicdatawereusedtoestimaterockporosityandgassaturation.Themodelresultswerein~ooda~reementwiththeproductionregimeofthewells.

  • 标签: Rock PHYSICS modeling Biot-Rayleigh theory heterogeneity
  • 简介:地震信号的变细经常用力量光谱的统计措施在频率领域被描绘。然而,常规Fourier基于变换的力量光谱评价方法受不了时间频率决定问题。Wigner-Ville分发,是科恩班时间频率分布的一个成员,拥有许多呼吁的性质,例如时间频率边缘的分发,时间频率本地化,等等。因此,Wigner-Ville分发为估计地震信号的变细提供一个新方法。这篇论文开始把简短介绍给Wigner-Ville分发和在减少跨术语的效果是有效的弄平的Wigner-Ville分发,然后基于Wigner-Ville分发的即时精力光谱为地震变细评价介绍一个方法。从在西方的中国的中央Tarim盆的一个真实数据例子被举说明建议方法的有效性。结果证明Wigner-Ville基于分发的地震变细评价方法罐头有效地检测礁石之间的差别,浅并且由他们的变细性质的泻湖外形,显示估计的地震变细能被用于礁石和浅碳酸盐水库描述。

  • 标签: WIGNER-VILLE分布 时频分布 地震衰减 储层预测
  • 简介:Sedimentationfromsoilerosionisacriticalreservoirwatershedmanagementissue.Duetothedifficultyoffieldinvestigations,empiricalformulasarecommonlyusedtoestimatethesoilerosionrate.However,theseestimationsareoftenfarfromaccurate.Aneffectivealternativetoestimatingsoilerosionistoanalyzethespatialvariationof137Csinventoryinthesoil.137Cscanbeadsorbedbythesoilandiswidelyassumedtochangeitsdistributiononlywhendisturbedbyrainfallandhumanactivities.Thus,137Csdistributedinsoilscanbeausefulenvironmentaltracertoestimatesoilerosion.Inthisstudy,thenetsoillossestimateis108,346t/yrandthegrosserosionandneterosionratesare10.1and9t/hayrrespectively.Thesedimentdeliveryratioisthereforeestimatedtobe0.9basedonthetwoerosionrates.Becauseofthesteephillsidesinthewatershed,only10%ofthesedimentyieldstayedinthedepositionsitesand90%wastransportedtotheriverasthesedimentoutput.Soilerosionestimatesfromspatialvariationsofthe137CsactivityintheBaishiriverwatershedshowedsatisfactoryaccuracywhencomparedtosedimentyielddata.Usingsoil137CsconcentrationsisthereforeafeasiblemethodforestimatingsoillossordepositioninTaiwan.Datasampling,analysisandresultofthisapproacharegiveninthispaper.

  • 标签: 土壤侵蚀 放射性元素 分水岭 空间分布 沉积物
  • 简介:Thehorizontalaccuracyoftopographicdatarepresentedbydigitalelevationmodel(DEM)resolutionbringsaboutuncertaintiesinlandscapeprocessmodelingwithrasterGIS.Thispaperpresentsastudyontheeffectoftopographicvariabilityoncell-basedempiricalestimationofsoillossandsedimenttransport.AnoriginalDEMof10mresolutionforacasewatershedwasre-sampledtothreerealizationsofhighergridsizesforacomparativeexamination.EquationsbasedontheUSLEareappliedtothewatershedtocalculatesoillossfromeachcellandtotalsedimenttransporttostreams.ThestudyfoundthatthecalculatedtotalsoillossfromthewatersheddecreaseswiththeincreasingDEMresolutionwithalinearcorrelationasspatialvariabilityisreducedbycellaggregation.TheUSLEtopographicfactors(LS)extractedfromappliedDEMsrepresentspatialvariability,anddeterminetheestimationsasshowninthemodelingresults.ThecommonlyusedUSGS30mDEMappearstobeabletoreflectessentialspatialvariabilityandsuitablefortheempiricalestimation.TheappropriatenessofaDEMresolutionisdependentuponspecificlandscapecharacteristics,appliedmodelanditsparameterization.ThisworkattemptstoprovideageneralframeworkfortheresearchintheDEM-basedempiricalmodeling.

  • 标签: GIS 数字模拟 动力效应模型 土壤损失
  • 简介:Cauchypriori基于分发的贝叶斯的AVO反射率倒置可以导致对大反射率敏感的稀少的估计。为倒置,协变性矩阵和调整条款的计算要求模型参数的优先的评价,它使反复的倒置弱非线性。同时,在模型参数之中的关系被假定线性。而且,反射率,倒置的结果,或有集成反射率恢复的累积错误的有弹性的参数很好不适合检测烃和液体。在贝叶斯的线性AVO倒置,相反,有弹性的参数能直接从prestack被提取没有为模型参数的线性假设的地震数据。就上述的方法的优点而言,贝叶斯的AVO反射率倒置过程被修改,当优先的概率分布和时间变体协变性也被考虑,Cauchy分发被探索。最后,我们为弱非线性的AVO波形倒置建议一个新方法。而且,线性假设被放弃,有弹性的参数例如P波浪速度,S波浪速度,和密度,能直接特别为大反射率的接口从地震数据被恢复。数字分析证明所有有弹性的参数能从prestack被估计地震数据甚至当地震数据的signal-to-noise比率是低的时。

  • 标签: AVO反演 弱非线性 弹性参数 柯西分布 波形反演 先验分布
  • 简介:Acoupledroutingforthetransportcapacityandtheenergyslopeisintroducedthroughthedefinitionofthecontrolfactormwhosevalueislinkedtothebedformconfiguration.Thecouplingaimstofurtherincorporatetheinteractionsoccurringinalluvialriversandthusenhancethepredictionofthefinesedimentfluxes,especiallyduringhighstreampowerevents.Basedonapredictiveruleforthecontrolfactormthatonlyinvolveswaterdepth,velocityandbedformconstitutivetexture,thenovelmethodisconfrontedtoobservationscollectedinoneofthemoststronglydynamicalluvialrivernamelytheLowerYellowRiver.Comparisonsbetweentimeseriesofmeasuredandcomputedconcentrationsillustratethatduringhighvelocityeventsthemaindynamicsofthesedimenttransportiscorrectlyreproduced.Themainadvantageofthepresentapproachistosupplyconsistenttimeevolutionsofsedimentconcentrationswithoutmakinguseofanydetailedshearinformation.

  • 标签: 冲积河流 运输能力 事件 电源 淤泥砂 上估计