马塞勒斯尤蒂卡页岩裂缝系统和应力场评价及水处理特征研究报告节选17doc

盛广石油信息技术研究中心马塞勒斯/尤蒂卡页岩裂缝系统和应力场评价及水处理特征研究报告节选1马塞勒斯/尤蒂卡页岩裂缝系统和应力场评价及水处理特征研究报告节选MarcellusDepositionalEnvironmentThewestwardsteppingnatureofDevonianblackshalescanbeexplainedintermsoffourtectophases(Ettensohn,2004)thatlinkbasindeformation,subsidence,andsedimentation.Thisdepositionalmodelincludesanactiveorogenichighlandthatcreatedawestwardmigratingforelandbasinandanassociatedsubaeriallyexposedperipheralforebulgeonthewestern,cratonsideofthebasin(Lash,2007).Theerodingorogenicfold-beltsuppliedsiliciclasticsediments,whichbecomefinergrainedfromeasttowest.Muchofthemobilesedimentwastrappedintheforelandbasin.Figure3.18showstheeightorganic-richDevonian/Mississippianshalesassignedtofourmajortectonicallycontrolledphases(Tectophases)ofsedimentdeposition(Lash,2007).TheMarcellusShalebelongstothesecondtectophase.Threeoftheregionalblackshalesareunderlainbycarbonatesthatmarktemporarybasintectonicquiescence.FortheMarcellusShaleincentralNewYork,theunderlyinglimestoneunitistheLowerDevonianOnondagaLimestone.Laterthrust-loading,subsidence,andmigrationoftheforebulgetothewestareindicatedbyonlapoftheUpperDevonianGeneseoblackshaleontotheerodedTullylimestone(Lash,2007;Smith2011).盛广石油信息技术研究中心马塞勒斯/尤蒂卡页岩裂缝系统和应力场评价及水处理特征研究报告节选2Figure3.18.EightDevonianorganic-richshalesandtheirrelationtofourmajortectonicallycontrolledphasesofsedimentdeposition.AfterLash(2007).Thedevelopmentofblackshaleswestofthebasinaxishascausedareinterpretationofdepositionalenvironments.Althoughorganic-richblackshaleshavetraditionallybeeninterpretedasbeingtheproductofdeep,sediment-starvedbasins(Fig.3.19),recentstratigraphicworkacrosstheAppalachianBasinindicatesashallow,low-oxygenenvironmentforDevonianshales.Inthisdepositionalmodel,theMarcellusShalewasdepositedduringDevoniangreenhouseconditionsinvolvingatectonicallyforced,ratherthananeustaticsealevel,transgression.TheseconditionsarepostulatedbySmithandLeone(2010)tohavebeenconducivetofreshwaterrunofffromlandandtothedevelopmentofshallowanoxicconditionsalongthemarginofnewlydevelopingtectonicperipheralforebulges(Fig.3.20).NotethatthelowerthreeblackshalesinFigure4overliecarbonates,asituationwhichisconsistentwiththeproductionofdissolved,ratherthansuspended,bedloadduringerosion.盛广石油信息技术研究中心马塞勒斯/尤蒂卡页岩裂缝系统和应力场评价及水处理特征研究报告节选3Figure3.19.Older,deep-water,downlappingmodeloftheDevonianblackshales,shownforacross-sectionacrossNewYork.AfterSmithandLeone(2010).Detailsofthedevelopmentofanoxicdepositionalenvironmentsundershallow-waterconditionsareshownonFigure3.20.Inthismodel,Devonianshaleswereprobablydepositedin30to150ft(9to45m)ofwaterwiththedeeperforelandbasintotheeastbeingmorefullyoxygenated,andwithsiliciclasticinputfromthemountainfrontcausingsiltstonesandgrayshalestoprogradefromeasttowestasshownonFigure3.21(SmithandLeone,2010).(a)(b)盛广石油信息技术研究中心马塞勒斯/尤蒂卡页岩裂缝系统和应力场评价及水处理特征研究报告节选4如想进一步了解请咨询舒老师010-57498139