ERC Advance Grant Trans-Atlanc Imaging of Lithosphere ......2015 on board the Schlumberger seismic...
Transcript of ERC Advance Grant Trans-Atlanc Imaging of Lithosphere ......2015 on board the Schlumberger seismic...
ERCAdvanceGrantTrans-Atlan3cImagingof
Lithosphere-AsthenosphereboundaryaStory
Sa#shSinghIPGParis
NTUSingapore
TransAtlan3cILAB:Summary
• ERCAdvanceGrant• SubmiFedin2012• Awardedin2013,3.5m€• StartedinNovember2014• LedtoasecondERCStartGrant,in2015• Fivemarineexperiments• ImagetheoceanicLithosphere-AsthenosphereBoundary(LAB)
• AlsofundingfromUKNERC,GermanDFG,USNSFandSchlumberger
CVmaFers:Sa3shSingh-1• GrewupinIndia• PhDattheUniversityofToronto,Canada,withayearofstayattheUniversityofCambridge
• Post-docatIPGParis,twoyears• JoinedtheUniversityCambridgein1990• Ledthecrea3onofLITHOSgroup• MovedtoParisin1999(keepingtheposi3oninCambridge)
• Ledthecrea3onofMarineGeosciencesDepartmentattheIPGParis
CVmaFers:Sa3shSingh-2By2012
• Published125papersinpeerreviewedjournals,10inScienceandNature
• Supervised27PhDstudentsandwassupervising10• Supervised25post-docs• 2009Dis3nguishedLecturerfortheEuropeanAssocia3onofGeoscien3stsandEngineers
• 2009LaureateoftheFrenchMinistryofResearchinScien3ficInnova3onandCrea3on
• ElectedFellowoftheAmericanGeophysicalUnionin2010
• AwardedGrandPrixoftheFrenchAcademyofSciencesin2011
IdeamaFersIn2011IhadtwoideasIdea1
• ApplytheideaIhaddeveloptostudytheSumatrasubduc3onzoneandapplytoJavasubduc3onzone,whichcanproduceadevasta3ngearthquakeandtsunamioffshoreJava
IdeamaFersIdea1
• Ihaddonefivemarineexperiments,includingtwofundedbyindustry(SchlumbergerandCGG)usingthestateofthearttechnology.
• Hadover30,000kmofseismicreflec3ondatafromtwoothercompanies(PGSandTGS)
• Hadpublishedover20papersinpeerreviewedjournals,includingtwoinNatureGeoscience
• Supervised4PhDstudentsandfivemasterstudents
IdeamaFersIdea1
• TherewasacryingneedfromIndonesiatostartthisproject
• Importantscien3ficproblem,wellproven,butnotthatoriginal
Gotfundedin2017(3.5m$)
IdeamaFersIdea2
• Therewas(s3llis)adebateaboutthenatureofthelithosphere-asthenosphereboundary(LAB),atthebaseofthetectonicplate
• Isitasharpboundary(500m)orthick(30-100km)transi3onzone?
• Doesthisboundarydeepenswiththeageofthelithosphere(from3-5kmatoceanspreadingcentreto100kmat100Ma)
• Exis3ngmethodsdonothavetheresolu3ontosolvethisproblem
IdeamaFersIdea2
• IthoughtofusingmyexperiencefromSumatra,whereIhadimaged500mthicklayerat60kmbelowtheseafloorusingindustrytechnology
• CanIusethistechnologytoimagetheLAB?• IndustryhadcomeoutwithabeFertechnologythanbefore,whichcanallowmetoimage500mthicklayerat100kmdepth,butthecostwouldbehorrendous
• Italktoindustryandseeiftheywouldbewillingtohelponthisproject,theysaidtheywouldifavesselhappenstobeinthearea
IdeamaFersIdea2
• Ihadneverworkedonsuchaproblemnorknewmuchaboutthedebate
• High-riskHigh-reward,soIoptedforthesecondidea.
Takeyour3me• PressurefromtheIPGPariswastowritetheproposalin2011
• Isaidno,Iwanttheideatomature,andwriteagoodproposal,andIdecidedwaitandtogofor2012
• Compe33onwasveryhigh,globallyandwithintheIPGParis(11candidates)
• Ispentmostofmy2012summeratScrippsIns3tuteofOceanographylearningabouttheproblem,anddrahingtheproposal
Thinkcarefully• Myprojectwasveryambi3ous:useallpossiblegeophysicalmethodsatthesameloca3ontoaddressthescien3ficques3ons:(1)seismicreflec3on,(2)seismicrefrac3on,(3)broadbandseismology,and(4)magnetotelluricmethod
• Iamonlyexpertatseismicreflec3on(mostexpensive)andrefrac3on.
• IaskedcolleaguesfromSouthamptoniftheywouldbeinterestedinbroadbandseismologyandScrippscolleagueformagetotelluric
Thinkcarefully• Thetotalcostoftheexperimentwouldbeabout15m€,butwecanonlyaskforamaximumof3.5m€
• SoIdecidedtofocusontheseismicreflec3on(6m€)andrefrac3on(3m€)partandproposedthattheothertwoexperimentscouldbeconsideredasapiggyback,subjecttofundingfromothersources.
• Loca3onofexperimentwascrucial:EquatorialAtlan3cbecauseofseismicvesselstransi3ngthisareafromSouthAfrica/AmericatoEurope
Trans-Atlan3cILAB:Dream
• Ultra-deepseismicreflec3onexperimentusingISOMETRIXsystem
• Ultra-longoffsetrefrac3onexperiment(70OBS)togetvelocity
• Tele-seismicusing30BBOS(receiverfunc3onandsurfacewave)
• 40Magnetotelluricdeployment(resis3vity)
• Fromzeroageto100Maoldoceaniclithosphere
• EquatorialAtlan3cOceanfor2Dstudy
• Profilecrossingthefracturezones
• PresentedatERCin2013
Dreamcometrue• IgotmyERCAdvancegrantin2013• UKNa3onalEnvironmentCouncilfundedship3meforthedeploymentofbroadbandseismometers
• KateRychert(Southampton)wroteanERCStar3ngGrantforbroadbandseismometerpartoftheprojectin2014andgotit.
• GermanScienceFounda3onfundedpartoftherefrac3onexperiment
• UnitedStatesNa3onalScienceFounda3onfundedthedeploymentofmagnetotelluricinstruments
• Wegotallthefundsweneeded
RealityHits• Contractnego3a3on:Oneyear• Gelngthevesselsandinstrumentstodotheexperiment,mostimportantlyindustryvesselforseismicreflec3on,specificallyasthecostofpetrolwentdownfrom120$/barrelto50$/barrel
• Fortunately,wehadaseismicvesselpassingthroughourstudyareainMarch2015.Followingalltheprocedureoftenderingetc.,wewentGhanatoboardthevessel.
• WefoundthatGhanahasclaimed350milesEEZ,insteadon200milesbefore,andourprofilewaswithinthenewGhana’sEEZlimit.
RealityHits• Wechangedtheprofilehopingtogostraight,butlaterwelearnedthatthisnewlinewillgothroughthedisputedareaoftheBri3shterritory,AscensionIsland,andhencehastochangeagain.
RealityHits• Butweenduphavingexcellentdata• WehavetwoPhDstudentsworkingonthesedataandapaperinNatureGeosciencehasbeenacceptedforpublica3on,afundamentaldiscovery.
Asoftoday• Seismicreflec3onexperimentcompletedin2015onboardtheSchlumbergerseismicvessel,WesternTrident
• BroadbandseismometerandmagnetotelluricinstrumentsweredeployedinApril2016andrecoveredinApril2017
• Thefirstrefrac3onexperimentistakingplacenowontheGermanR/VMariaSMerian
• Thesecondrefrac3onexperimentisplannedinSeptember-October2018onboardFrenchR/VL’Atlante
Acknowledgements• ERCAdvancedGranttoSingh(IPGP)• ERCStartGranttoRychert(NOC)• UKNERCforship3meforTeleseismicandMTstudy(Harmon,NOC)
• GermanScienceFounda3onforship3meandrefrac3onstudy(Grevemeyer)
• USNSFforfundingMTdeployment(Constable,Scripps)
• Schlumberger(WesternGeco)forprovidingWesternTridentforultra-deepseismicstudy
Surveydetails• Streamer:12kmlong• Pressure(3.125m),Az,and
Ay(0.76m)components• Towat30mwaterdepth• Numberofstreamers:1• Source:10170cubicinch• Shotinterval:50m,62.5m
and75m• Recordlength:20,25,and
30s• 2200km2Ddata(0-75My)
(A-G)• 600kmAcrossFracture
zones(G-H)• Changeoflinesdueto350
milesEEZrequirements• Four3mezones• Crossingoftheequator
April2015
WesternTrident
BBOBSandMTExperiment
UKNERCship3meERCStartGrantUSNSFforMTFebruary2016toApril2017Rychert+Harmon(Southampton)Constable(Scripps)
Refrac3onstudy:LITHOS
2.LITHOS70OBS0-50MaAfricanplate2017onGermanvessel
Refrac3onstudy1. SPARC:201860OBS0-25MaGreatFracturezonesL’Atlante
Acknowledgements
• TheprojectisfundedbyERC,UKNERC,GermanScienceFounda3on,andUSNSF
• SchlumbergerprovidedIsoMatrixvessel,WesternTrident