資源描述：
《STRATA反演軟件介紹(精)課件.ppt》由會員上傳分享，免費(fèi)在線閱讀，更多相關(guān)內(nèi)容在教育資源-天天文庫。
1、EARTHIMAGINGSOLUTIONS1STRATA2Dand3D Post-StackSeismicModelling,Processing&April1999Inversion2STRATAisaninteractive2Dand3Dmodellingandinversionprogramwhichtransformspost-stackseismictracestovelocityoracousticimpedancetraces.Theprogramincludesoptionsforbasicseismicprocessing,waveletextraction,logedit
2、ingandinterpretation,aswellasdifferentmethodsofperforminginversion.3OverviewofInversionPre-StackInversionTravelTimeInversion(Tomography)AmplitudeInversion(AVO)WaveFieldInversionBandlimitedInversionSparse-spikeInversionModel-basedInversionPost-StackInversionSeismicInversionMethodsAmplitudeInversion(
3、STRATA)4Theinversionprocessistodeterminetheearthimpedancefromthegivenseismictracebasedontheconvolutionalmodelseismic=wavelet*reflectivity+noiseAssumptionsTheseismicdataarealreadystacked,migratedandnomultiples.Eachtracedependsonlyontheimpedancedirectlybelowthetracelocation.Thewaveletisconstantandnot
4、varyingwithtime.Thenoiseisrandom,whitenoise,uncorrelatedwiththeseismic.Thereisnocoherentnoise.Objective5Non-UniquenessProblem!非單值問題（CHJ注）Allinversionalgorithmssufferfromthenon-uniquenessproblem.Thismeansthatthereismorethanonepossiblegeologicalmodelconsistentwiththeseismicdata.Inpractice,thisproblem
5、ishandledbyusinggeologicalconstraints,providedbywelllogs.6BasicConceptofSTRATASeismicDataVelocity/DensityControl(Logs)BuildModelInvertSeismic7BasicSteps(e.g.ModelBasedInversion)(1)Readseismicandwelllogs.(2)Extractastatisticalwaveletfromtheseismic.Correlatelogsandextractagainthebestwaveletusingthewe
6、lllogs.(4)Buildinitialmodel.Setupverticalandlateralinterpolation.(5)Applyinversionandvalidatetheoutputimpedanceandsynthetic.(3)Pickorimporthorizons.ImportWellLogOpenSeismicProcessSeismicExtractWaveletExtractWaveletusingLogCreateSyntheticPickSeismicBuildModelInversionCorrelateLog8Step1:DataInput(1)R
7、eadseismicandwelllogs.(2)Extractastatisticalwaveletfromtheseismic.Correlatelogsandextractagainthebestwaveletusingthewelllogs.(4)Buildinitialmodel.Setupverticalandlateralinterpolation.(5)Applyinversionandval
