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TheNISAR-ISROSARMission

Trackingtheground’supsanddowns Management of subsurface fluid reservoirs is criticallyimportanttotheeconomicandenvironmentalhealthofoursociety. Fluids such as oil, gas and water all must beextracted from the subsurface at considerable effort andexpense. Fluidsarealso injected into the subsurface fora

range of purposes, including disposal of wastewaterbyproductsfromoilproduction,ortofurtherstimulatethereservoir (oil,gas,orgeothermal).Theseactivitiesalloccurdeepunderground,challengingourabilitytodeterminethestate of the resource. The relative inaccessibility of theseresourcesmeansthattheeffectsofmanagementdecisionscanbedifficulttoassess.

ManagingResourcesUnderfoot

TheNISARsatellitemissionwillprovidehigh-resolutiongroundmovementmapsonaglobalbasiswithweeklysampling.Observationswillbeuninterruptedbyweatherandfacilitatesaferesourcedevelopmentbyimprovingunderstandingofprocessesthatimpactregionsundergoingactiveextractionorinjectionofsubsurfacefluids.

TheNISARMission–Reliable,ConsistentObservations

TheNASA–ISROSyntheticApertureRadar(NISAR)mission,acollaborationbetweenthe National Aeronautics and Space Administration (NASA) and the Indian SpaceResearchOrganization(ISRO),willprovideall-weather,day/night imagingofnearlytheentire landandicemassesoftheEarthrepeated4-6timespermonth.NISAR’sorbitingradarswillimageatresolutionsof5-10metersto identifyandtracksubtlemovementoftheEarth’s landand itssea ice,andevenprovide informationaboutwhatishappeningbelowthesurface.Itsrepeatedsetofhighresolutionimagescaninformresourcemanagementandbeusedtodetectsmall-scalechangesbeforetheyarevisibletotheeye.Productsareexpectedtobeavailable1-2daysafterobservation,andwithinhoursinresponsetodisasters,providingactionable,timelydataformanyapplications.

Fluid injection and extraction – finding the balanceEfforts to utilize subsurface resources, includingwater, oil, and gas,necessarilyinvolvetheextractionandinjectionoflargevolumesoffluidfromtheground–ofteninareasthatalsohostvaluableinfrastructureandlargepopulationcenters.RecentincreasesinearthquakeactivityinthecentralUnitedStatesunderscoretheneedtobetterunderstandhowtomanagetheratesandvolumesoffluidextractionandinjection.Observationsof howthegroundsurfacerises and fallsabove a fluidreservoir illuminate the changing environment at depth and enableinformedmanagementchoices.Image Credits: Kinemetrics seismograph by Yamaguchi; traffic byLeoboudv;pumpjackbyFicelloguy;Highway302byUSGS

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Continuedfromfrontpage

The past decade has seen a substantial increase inthe number of earthquakes triggered by bothinjection and production of subsurface fluids, withOklahomanowexperiencingmoreearthquakeseachyear than California. Globally, radar imagery hasalready been used to characterize the extent ofreservoirdepletionaroundoil,gasandwaterwells,with renewedeffortsby researchers tounderstandthecomplexnetworksoffaultssurroundingtheareasofexploitation.Thepatternofsubsidenceorupliftisa window into the pattern of fluid flow below –whethertheactivityisconcentratednearthewellasexpected,orifitjumpsintoaneighboringregioncanbeanimportantindicatorofstabilityorproblemstocome.The increased frequency of earthquakes in regionssuch as the central United States affects regionalpopulations and infrastructure. Operationsmanagers at individual well sites, insurancecompanies and disaster responders all requireinformationabouttheprobabilitiesofstrongshakingand aftershocks after a large event to inform thepublic and manage disasters. Characterizing thecurrentpatternsofearthquakesweareexperiencing

will help us understand how to anticipate andmitigatefuturedamage.The energy needs of the world’s population willcontinuetogrow,requiringnewandinnovativewaysof meeting them. Satellites that provide synopticviews of the globe from space can aid us inmonitoring and characterizing the effects of theseefforts. The upcoming NISAR mission will have adependable observation plan to collect highresolutionimagesof90%oftheEarth’slandsurfacesat regular intervals (12-day repeat orbits), whichcontrastswithmonitoringbyexistingradarsatellites,whichtypicallyfocusonlyonareasofinteresttothespecific government or scientific agency thatlaunchedthemission. For instance,theoilfields inTexas and the central United States were notobserved frequently, if at all, by most previousmissions. Theobservationsmadeoverthelifetimeof NISAR will be a giant step forward in ourunderstanding of subsurface fluid flow andassociated seismicity, and will inform the nextgeneration of methods for characterizing andmanagingtheseresources.

Numberofearthquakesequenceseachyearthatcontainatleastonemagnitude3orlargerearthquake,since1973.FromMcGarretal.,2015,inthejournalScience.

Recentadvancesinthetechnologyusedinhydrocarbonproduction,including enhanced oil recovery, are associated with a dramaticincrease in earthquakes felt in the centralUnited States since themid-2000s. Damagingearthquakesonlyappeartoberelatedtoasmallfractionofwells,butthereisnotyetenoughdatatodefinitivelydetermineinadvancethesafetyofoperationsataparticularsite.Earthquakelocationsderivedfromseismicdata(seefigureatright)illuminate part of the picture. New research shows that inducedearthquakes may behave in slightly different ways than “natural”events,providingapotentialpathwaytobetterunderstandingandmanagingthem.However,seismicdataisblindtotheslow,longertermdeformationof the ground surfaceassociatedwithpumping,injection and even slow, creeping movement on faults that willeventually rupture in a more damaging earthquake. NISAR canprovidethemissinglinktothispuzzle,complementingtheavailableseismicdataandhelpingtotrackhowpatternsoffluidflowbeneaththesurfacerelatetopatternsofobservedearthquakes.

Increasing rates of earthquakes in the central United States.

-California-Oklahoma

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Oilfieldsandaquifersimagedfromspace: Monitoringchanges in shallowaquifer systemsandunderstanding the geologic controls on their basicconfiguration is rapidly becoming an essentialchallenge, as society attempts to respond toincreased pressures on water resources. Thesechallengesarepresentglobally inaridregions,withthe impacts acutely felt throughout the westernUnited Sates, and especially in southern California.Historically,understanding regionalaquifer systemshas relied on monitoring wells that are sparselydistributedacrossimpactedareas.Satellite-basedradarimagery,whenavailable,canbeused tocharacterizehowtheEarth’s surfacewarpsanddeformsaboveactively-managedoilandwaterreservoirs. However, theseobservationscannotbemadewhenthegroundsurfacechangessignificantly

betweenimageacquisitions–growthofcrops,tillingoffields,treessheddingtheirleavesareallprocessesthatdegradedataquality. TheregionsinCaliforniashown below have had some of the best radarcoverageavailableworldwide,butstillcontainareaswithrapidchangewherethetimeintervalbetweenimagesistoolong.Otherregions,suchastheCentralUnitedStates,havehadfarlessdatacoverage.NISARdatawouldbeacquiredalmost3timesmorefrequentlythanthedatausedintheexamplesbelow,and would be acquired regularly over the entireUnitedStates.Thiswouldallow imagingofareas inOklahoma, Texas and Kansas that experience bothactive agriculture and hydrocarbon/water resourcedevelopment.

Right:RateofgroundsubsidenceinCentralCaliforniaimagedusingtheEuropeanSpaceAgency’sENVISATsatellite,averagedover the time period 2008-2010 (color), overlain on Landsatimagery (grayscale). Both the results of extraction (red) andinjection(blue)canbeseen.Grayareasareregionswherethegroundsurfacechangedsignificantlybetween images,due tocropgrowthandtillingoffields.Roadsandcitiesstillyieldhigh-qualityresults.

Examples:

Left: NISAR data will permit systematic mapping and monitoring ofshallowaquifers.Bothlongtermandseasonalchangescausemovementof the surface. Inmany cases,mapping the timing of themaximumseasonalsurfaceupliftorsubsidencecandelineatetheboundariesofthesubsurfaceaquiferswithfinedetail.Inthisexample,takenfromthegreaterLosAngelesMetropolitanareainSouthernCalifornia,colorindicatesthetimeduringtheyearwhenpeakmotionoccurs. Theaquiferischaracterizedbysharpboundaries,someassociatedwithfaultsthathaverupturedinearthquakes.

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FORMOREINFORMATION:Generalintroduction:https://earthquake.usgs.gov/research/induced/http://nisar.jpl.nasa.gov/CommunityreportsPetersen,M.D.etal.(2016),2016One-yearseismichazardforecastfortheCentralandEasternUnited

Statesfrominducedandnaturalearthquakes,U.S.GeologicalSurveyOpen-FileReport2016-1035,52p.,doi:10.3133/ofr20161035.

McGarr,A.etal.(2015),Copingwithearthquakesinducedbyfluidinjection,Science,347;doi:10.1126/science.aaa0494.

NationalResearchCouncil(2013),CommitteeonInducedSeismicityPotentialinEnergyTechnologies.Inducedseismicitypotentialinenergytechnologies.NationalAcademiesPress,2013.

NationalEarthquakeResilience:Research,Implementation,andOutreach(2011),NationalAcademiesPress,Washington,D.C.

Relevantscientificpapers.

Jha,B.,etal.(2015),Reservoircharacterizationinanundergroundgasstoragefieldusingjointinversionofflowandgeodeticdata,Int.J.Numer.Anal.Meth.Geomech,39,1619–1638.

Yang,Qi.,etal.(2015),InSARmonitoringofgrounddeformationduetoCO2injectionatanenhancedoilrecoverysite,WestTexas,InternationalJournalofGreenhouseGasControl41;doi:10.1016/j.ijggc.2015.06.016.

Hough,S.E.(2015),Shakingintensityfrominjection-inducedversustectonicearthquakesinthecentral-easternUnitedStates,TheLeadingEdge34;doi:10.1190/tle34060690.1.

Keranen,K.M.etal.(2014),SharpincreaseincentralOklahomaseismicitysince2008inducedbymassivewastewaterinjection,Science,345;doi:10.1126/science.1255802.

Barnhart,W.etal.(2014),Seismologicalandgeodeticconstraintsonthe2011Mw5.3Trinidad,ColoradoearthquakeandinduceddeformationintheRatonBasin,J.Geophys.Res.,119;doi:10.1002/2014JB011227.

Ellsworth,W.L.(2013),Injection-inducedearthquakes,Science,341;doi:10.1126/science.1225942.González,P.J.etal.(2012),The2011Lorcaearthquakeslipdistributioncontrolledbygroundwater

crustalunloading,NatureGeoscience,5;doi:10.1038/ngeo1610.

Ketelaar,V.B.H.(2009),SubsidenceduetohydrocarbonproductionintheNetherlands,In:SatelliteRadarInterferometry:SubsidenceMonitoringTechniques,Springer,London,doi:10.1007/978-1-4020-9428-6_2

NationalAeronauticsandSpaceAdministration Formoreinformation,visithttp://nisar.jpl.nasa.gov/applications

JetPropulsionLaboratory/CaliforniaInstituteofTechnology/Pasadena,California/www.jpl.nasa.gov