Understanding and Responding to Earthquake Hazards Carol A. Raymond Paul R. Lundgren Søren N....

Understanding and Understanding and Responding to Responding to

Earthquake HazardsEarthquake HazardsCarol A. Raymond Carol A. Raymond

Paul R. LundgrenPaul R. Lundgren

Søren N. MadsenSøren N. MadsenJet Propulsion LaboratoryJet Propulsion Laboratory

AndAnd

John B. RundleJohn B. RundleUniversity of ColoradoUniversity of Colorado

2

Global Earthquake Satellite System Study

SummarySummary Discuss ongoing Global Earthquake Satellite Discuss ongoing Global Earthquake Satellite

System Study (GESS)System Study (GESS) Objectives of the study are to develop a Objectives of the study are to develop a

linked science and technology program linked science and technology program plan that would lead to understanding of plan that would lead to understanding of faults and fault systems and achieve short-faults and fault systems and achieve short-term, targeted earthquake forecasting by term, targeted earthquake forecasting by 2020. 2020. – Develop detailed science requirements with Develop detailed science requirements with

science community input (EarthScope and science community input (EarthScope and beyond)beyond)

– Develop system architecture concepts for both Develop system architecture concepts for both short term (next 5 years) and long term (next short term (next 5 years) and long term (next 20 years)20 years)

3

Global Earthquake Satellite System StudyObserving Crustal Observing Crustal DynamicsDynamics

Surface change (deformation) is the key Surface change (deformation) is the key observableobservable– Considered the highest priority of the NASA Solid Considered the highest priority of the NASA Solid

Earth Science community (InSAR everywhere, all the Earth Science community (InSAR everywhere, all the time)time)

– Models and seismicity yield third dimension (depth)Models and seismicity yield third dimension (depth)

Electromagnetic, IR/thermal emissions may Electromagnetic, IR/thermal emissions may indicate state of stressindicate state of stress– More research is needed, and systematic data More research is needed, and systematic data

analysis of high resolution data setsanalysis of high resolution data sets– Addressed by ASTER, MODIS, Demeter, swarmAddressed by ASTER, MODIS, Demeter, swarm

4


Future Observing SystemFuture Observing System Seismicity yields information on Seismicity yields information on

the energy released in discrete the energy released in discrete events and illuminates fault events and illuminates fault planesplanes– Need dense digital seismic Need dense digital seismic

network (USGS)network (USGS) Global Positioning System (GPS) Global Positioning System (GPS)

measurements track surface measurements track surface motions on specific points with motions on specific points with high time resolutionhigh time resolution– Need dense, continuous GPS Need dense, continuous GPS

arrays (SCIGN, PBO)arrays (SCIGN, PBO) Interferometric Synthetic Interferometric Synthetic

Aperture Radar (InSAR) measures Aperture Radar (InSAR) measures the deformation of the surface as the deformation of the surface as a continuum, but usually with a continuum, but usually with poor time resolutionpoor time resolution– Need an InSAR constellation to Need an InSAR constellation to

improve temporal resolutionimprove temporal resolution

5


Multi-space-time scale strain monitoringCo-seismic displacements

Fault geometry/slip Complex slip distribution Dynamic rupture parameters

Postseismic motion Afterslip and long-term stress transfer

Highly transient stress fields and postseismic stress redistribution at scale of fault system

Full-resolution postseismic deformation

Slow earthquakes Fault geometry/slip Complex slip distribution

Aseismic slip Fault geometry/slip Complex slip distribution

Interseismic strain accumulation

Identify blind thrusts Identify earthquake precursors and stress transients

Disaster ManagementChanges in Built Environment Decorrelation Maps

Hazard Assessment Postseismic stress redistribution at scale of fault system

Identify earthquake precursors and stress transients

4-8 days < 24 hrs 1 secIncreasing temporal resolution

Surface Deformation Science Surface Deformation Science RequirementsRequirements

Increasing accuracy

Real Aperture Radar

6

Global Earthquake Satellite System StudySurface Deformation Measurement Surface Deformation Measurement

RequirementsRequirements

MinimumMinimum GoalGoalDisplacement accuracyDisplacement accuracy 25 mm 25 mm

instantaneousinstantaneous5 mm 5 mm

instantaneousinstantaneous

3–D displacement 3–D displacement accuracyaccuracy

50 mm (1 week)50 mm (1 week) 10 mm (1 day)10 mm (1 day)

Displacement rateDisplacement rate 2 mm/yr (over 10 2 mm/yr (over 10 y)y)

<1 mm/yr (over 10 <1 mm/yr (over 10 y)y)

Temporal AccessibilityTemporal Accessibility 8–days8–days 1–day or less1–day or less

Daily CoverageDaily Coverage 66101066 km km22 Global (land)Global (land)

Map regionMap region ±60° latitude±60° latitude GlobalGlobal

Spatial resolutionSpatial resolution 100 m100 m 10 m10 m

Geo-location accuracyGeo-location accuracy 25 m25 m 3 m3 m

SwathSwath 100 km100 km 500 km500 km

Data latency in case of Data latency in case of eventevent

1 day1 day 2 hours after acq.2 hours after acq.

7


Observations to PredictionObservations to Prediction

InSARInSAR

Seismicity Seismicity

GPSGPS

electric fieldelectric field

magnetic fieldmagnetic field

thermal IRthermal IR

Community ModelingCommunity ModelingEnvironmentEnvironment

• Model validationModel validation• Model evolutionModel evolution• Forward predictionForward prediction• Grid-based computingGrid-based computing• Data MiningData Mining• General Earthquake General Earthquake

Model (GEM) is Model (GEM) is prototypeprototype

Dynamic Dynamic Earthquake Earthquake Hazard Hazard AssessmentAssessment(monthly? to (monthly? to annual/USGS)annual/USGS)

Physics-based Physics-based models of models of precursory precursory

signalssignals

FEMA, CA OES FEMA, CA OES and Int’l Aid and Int’l Aid CommunityCommunity

8


Responding to EQ HazardsResponding to EQ Hazards Earthquake hazard assessments:Earthquake hazard assessments:

– Prioritize retrofitting of vulnerable structures Prioritize retrofitting of vulnerable structures – Update building codesUpdate building codes– Increase earthquake drills for emergency services Increase earthquake drills for emergency services

and public (schools)and public (schools)– Public education campaignsPublic education campaigns– Increase monitoring of hazardous areasIncrease monitoring of hazardous areas

Disaster:Disaster:– Rapid assessment of damage in all weather via Rapid assessment of damage in all weather via

decorrelation maps received on handheld devicesdecorrelation maps received on handheld devices– Updated hazard assessment due to stress transfer Updated hazard assessment due to stress transfer

and loading of nearby faultsand loading of nearby faults

9


Faults Can Be Modeled as Interacting Faults Can Be Modeled as Interacting Systems:Systems:

Virtual CaliforniaVirtual California

Southern California Seismicity Fault Representation

Courtesy Paul Rundle and John RundlePhysical Review Letters, 2001

VC provides an assessment of the space-time VC provides an assessment of the space-time complexity of seismicity and fault system behaviorcomplexity of seismicity and fault system behavior

Community ModelingCommunity Modeling

10


Pre- minus Post-Seismic Pre- minus Post-Seismic Displacements: Synthetic InSARDisplacements: Synthetic InSAR

The pre-seismic The pre-seismic state is subtracted state is subtracted from the post-from the post-seismic stateseismic state

The differences are The differences are concentrated along concentrated along the portions of the the portions of the San Andreas that San Andreas that are about to initiate are about to initiate earthquakesearthquakes

The observable The observable difference is ~ 3 CMdifference is ~ 3 CM

Stable sliding Stable sliding (stress (stress smoothing) smoothing) preceding preceding earthquakes earthquakes can be can be measuredmeasured

Courtesy John Rundle

11


InSAR Concept InSAR Concept AlternativesAlternatives

Low Earth Orbit (LEO) Low Earth Orbit (LEO) 780 km elevation780 km elevationECHO/LightSAR class satellite ECHO/LightSAR class satellite Cheapest option, 8-day repeatCheapest option, 8-day repeat

Enhanced Low Earth Orbit (LEO+)Enhanced Low Earth Orbit (LEO+)1325 km elevation, 6-day repeat1325 km elevation, 6-day repeat50–80% larger targeted range, stable orbits50–80% larger targeted range, stable orbitsTechnology as LEO but larger antenna and powerTechnology as LEO but larger antenna and power

Constellation of LEO+ satellites (2/4/8… satellites)Constellation of LEO+ satellites (2/4/8… satellites)

Geosynchronous SAR (GeoSyncSAR)Geosynchronous SAR (GeoSyncSAR) 35789 km elevation, 35789 km elevation,1-day repeat, 1 satellite covers ±60° in longitude1-day repeat, 1 satellite covers ±60° in longitude5500 km “targetable” swath on either side of ground track 5500 km “targetable” swath on either side of ground track Very large antenna (30 m @ L-band), moderately large power Very large antenna (30 m @ L-band), moderately large power (65 kW DC)(65 kW DC)

12


LEO AccessibilityLEO Accessibility versus versus GEO CoverageGEO Coverage>95% coverage in >95% coverage in 8 hrs with 3 sats8 hrs with 3 sats

>95% access in 8 hrs >95% access in 8 hrs with 8 satswith 8 sats

13


Geosynchronous ModesGeosynchronous ModesHigh-resolutionHigh-resolution::

Stagger bandwidth over consecutive days Stagger bandwidth over consecutive days => 80 MHz bandwidth => 2.5 meter range resolution at 45°=> 80 MHz bandwidth => 2.5 meter range resolution at 45°

Dual-side Scan SARDual-side Scan SAR 11000 km combined swath 11000 km combined swath=>100 meter resolution @ 25 looks=>100 meter resolution @ 25 looks

Scan-SAR with 3 aspect anglesScan-SAR with 3 aspect angles (45° forward, broadside, 45° (45° forward, broadside, 45° backward) of 2800 km swath on both side of nadirbackward) of 2800 km swath on both side of nadir=>100 meter resolution @ 8 looks=>100 meter resolution @ 8 looks

SpotlightSpotlight mode dwelling beam for hours on target, for mode dwelling beam for hours on target, for disaster managementdisaster management

14


3-GEO 3-GEO InstantaneousInstantaneous

15


Technology Challenges Technology Challenges Sub-centimeter (!!) tropospheric water vapor delay Sub-centimeter (!!) tropospheric water vapor delay

correctionscorrections– Radar or radiometer data alone accurate to 2-3 cm level of Radar or radiometer data alone accurate to 2-3 cm level of

range delayrange delay– Co-boresighted IR/microwave sounding may yield 1 cm Co-boresighted IR/microwave sounding may yield 1 cm

accuracy in delayaccuracy in delay– Mesoscale models that ingest sounding and radar data will Mesoscale models that ingest sounding and radar data will

likely deliver the sub-cm correction likely deliver the sub-cm correction – GPS, permanent scatterers and corner cubes all improve the GPS, permanent scatterers and corner cubes all improve the

wet delay correctionwet delay correction

30-m antenna (deployable) for GEO30-m antenna (deployable) for GEO– Analysis and component developmentAnalysis and component development

New processing system for GEONew processing system for GEO

16

Global Earthquake Satellite System StudyFlexible Hexagonal Flexible Hexagonal AntennaAntenna

• L-band/X-band membrane antenna aperture• Flexible T/R module• Ultra high efficiency SiC Class-E/F power amplifiers• Agile 2-D beam scanning• MEMS heat pipes for thermal management• Optical RF/DC signal distribution• Inflatable/deployable structures• Integrated solar panels

Symmetric telescoping booms

Inflatable/deployable struts

L-band RF membrane

aperture

Membrane Solar Arrays

X-band Shared-aperture

comm antenna

17


GESS RoadmapGESS Roadmap ObservationsObservations

– 2003-06:2003-06: ECHO or ECHO-like InSAR satellite ECHO or ECHO-like InSAR satellite (EarthScope)(EarthScope)

– 2006-2010:2006-2010: 2-3 satellite LEO or LEO+ InSAR 2-3 satellite LEO or LEO+ InSAR constellation; magnetometer constellationconstellation; magnetometer constellation

– >2010:>2010: GEO InSAR constellation? GEO InSAR constellation? TechnologyTechnology

– Large deployable antennasLarge deployable antennas– Processing system for GEO observationsProcessing system for GEO observations– High resolution atmospheric models ingesting High resolution atmospheric models ingesting

radar dataradar data

Understanding and Responding to Earthquake Hazards Carol A. Raymond Paul R. Lundgren Søren N....

Documents

Transcript of Understanding and Responding to Earthquake Hazards Carol A. Raymond Paul R. Lundgren Søren N....