《全球油气分布》basin-formation

IGlobaldistributionofgiantfieldsIIPlatetectonicsandBasinclassificationIIIDistributionofgiantfieldsindifferenttypesofbasinsIVSummaryLECTUREOUTLINEGlobalPlateTectonicsTheoryLandmarkdevelopmentof20thcenturyAcceptedasfactbychildreninprimaryschoolsTheframeworktoviewmostgeologicalprocesses“Therigidlithosphereconsistsofabout20segmentscalledplates:e.g.Pacificplate”GlobalPlateTectonicsTheoryProspectPlaySystemBasinTectonicsConceptsPlay:oneormoregeologically(orengineering)relatedprospects.Prospect:apotentialtrapthatmustbeevaluatedbydrillingtodeterminewhetheritcontainscommercialquantitiesofpetroleum.Oncedrillingiscomplete,theterm“prospect”isdropped.Thesitebecomesadryholeoraproducingfield.Trap:itconsistsofgeometricarrangementofpermeable(reservoir)andless-permeable(seal)rockwhich,whencombinedwiththephysicalandchemicalpropertiesofsubsurfacefluids,canallowhydrocarbonstoaccumulate.CoresphereMosaicofrigidplatesconstitutingtheearth’soutershellPlateBoundariesContinentsandOrogeny•Thereisagenerallarge-scalestructureofcontinents:–Oldstablecoressurroundedbyyoungerdeformedbelts9ContinentsandOrogeny•Wherethecratoniscoveredbyarelativelyflat-lyingundeformedsequenceofPaleozoicandlatersediments,itiscalledaplatform.Withintheplatform,theremayberoughlycircularorovalregionsthatexperiencedprolongedsubsidenceandaccumulatedthicksedimentarybasins.Inbetweenbasinstheremayberegionsthathavelongstoodrelativelyhighandaccumulatedlittlesediment.Ifroughlylinear,thesearearches;ifroughlycircular,thesearedomes•Eachcontinenthasregionsintheinterior,farfromitsmargins,thathavenotundergonesignificanttectonicdeformationforalongtime.Thestableregions,undeformedsincePrecambriantime,arecalledcratons(particularlyifArcheaninage).WherePrecambriancrystalline(i.e.,igneousandmetamorphic)rocksareexposedoverawidearea,thatpartofthecratoniscalledashield(example:Canadianshield).ContinentsandOrogeny•Neartheedgesofplatformsarefoundtwoothertypesofsedimentarybasinsthatoriginatedaspartsoforogenicbeltsandbecameincorporatedintothecratonbylaterstabilization.Theseinclude–orogenicforedeepsformedduringorogeniceventsandfilledwithsedimentshedoffanorogenicmountainbeltand–passivecontinentalmarginsequences(example,GulfCoast).•Therestofcontinentalareaismadeupoforogenicormobilebelts.Thesetypicallyboundcratonicregionsintheinteriorofaggregatecontinentsandsurroundthecratonsaroundmostofthemarginsofeachcontinent,wherecollisions,subduction,andriftingmostoftenoccur.11Theoldestknownsupercontinent:Rodinia（罗迪尼亚）.Itwasformedabout1100millionyearsaagoandbrokeapart~750millionyearsago.Rodiniasplitinto2halvesapproximately750millionyearsago,openingthePanthalassicOcean（古大洋）.SRodiniarotatedsouthwardstowardstheice-coveredSouthPole.ThenorthernhalfofRodinia,composedprimarilyofAntarctica,Australia,India,Arabia,andthecontinentalfragmentsthatwouldonedaybecomeChina,rotatedcounter-clockwise,northwardsacrossthefrigid,NorthPoleStratigraphicEffectiveSourceRocksgivenasapercentageofworld’soriginalpetroleumreservesgeneratedbytheserocksThismapillustratesthebreak-upofthesupercontinent,Rodinia,whichformed1100millionyearsago.TheLatePrecambrianwasanIceHouseWorld,muchlikethepresent-day.continentalfragmentsthatwouldonedaybecomeChinaBetweenthetwohalvesofRodinialayathirdcontinent-theCongocraton,madeupofmuchofnorth-centralAfrica.ItwascaughtinthemiddleasthetwohalvesofRodiniacamecrashingdownonit.BytheendofthePrecambrian,about600millionyearsago,thethreecontinentscollidedtoformanewsupercontinentcalledPannotia(潘诺西亚).Themountain-buildingeventassociatedwiththiscollisioniscalledthePan-Africanorogeny.Anewocean,theIapetus(巨神海)Ocean,widenedbetweentheancientcontinentsofLaurentia(劳伦西亚,NorthAmerica),Baltica(波罗地,NorthernEurope),andSiberia.Gondwana,thesupercontinentthatwasassembledduringthePan-Africanorogeny,wasthelargestcontinentatthistime,stretchingfromtheEquatortotheSouthPole.DuringtheOrdovicianPeriod,warmwaterdeposits,suchaslimestonesandsalt,werefoundintheequatorialregionsofGondwana(Australia,India,China,andAntarctica),whileglacialdepositsandice-rafteddebris(冰漂碎屑)occurredinthesouthpolarareasofGondwana(AfricaandSouthAmerica).DuringtheOrdovicianancientoceansseparatedthebarrencontinentsofLaurentia,Baltica,SiberiaandGondwana.TheendoftheOrdovicianwasoneofthecoldesttimesinEarthhistory.IcecoveredmuchofthesouthernregionofGondwana.SilurianPetroleumSourceRockMapBymiddlePaleozoictime,approximately400millionyearsago,theIapetusOceanhadclosedbringingLaurentiaandBalticacrashingtogether.Thiscontinentalcollision,precededinmanyplacesbytheobductionofmarginalislandarcs,resultedintheformationoftheCaledonidemountainsinScandinavia（斯堪地那维亚半岛）,northernGreatBritainandGreenland,andtheNorthernAppalachian（阿帕拉契）mountainsalongtheeasternseaboardofNorthAmerica.UpperDevonian-BasalCarboniferousPetroleumSourceRockMapDuringtheEarlyCarboniferousthePaleozoicoceansbetweenEuramericaandGondwanabegantoclose,formingtheAppalachianandVariscan（维利斯堪）mountains.BytheLateCarboniferousthecontinentsthatmakeupmodernNorthAmericaandEuropehadcollidedwiththesoutherncontinentsofGondwanatoformthewesternhalfo