Capturing global seismic potential from GEM’s fault, quake, and strain datasetsRoss S. Stein GEM Scientific Board chair, and U.S. Geological Survey geophysicist

Instrumental quakes

Active faults

Historical quakes

Strain rate Ground motion

prediction equations

Exposure

Population

Buildings

Vulnerability

Damage data

Fragility functions

Decision tools

Loss amplifiers

Risk transfer tools

Retrofit cost-benefit tools

Risk rankings and indices

Hazard(faulting & shaking)

Exposure andVulnerability

(deaths, damage, dollars)

Social Impact(mitigation actions)

GEM’s GLOBAL DATASETS, a €10M investment

ISC‐GEM Catalog: 20,000 earthquakes, 1900‐2009

Cut‐off Magnitudes:

M≥7.50 since 1900M≥6.25 since 1918M≥5.50 since 1965

15,000 seismic 

bulletins from 300 

institutions

NewOld

ISC-GEM Catalog: New magnitudes, locations, and depths for all

quakes

Guatemala

Puerto Rico

Colombia

Guatemala

Puerto Rico

Colombia

Depth (km)

Storchak, Di Giacomo, Bondár, Engdahl, Villaseñor, Lee, Harris and Bormann (submitted)

ISC-GEM vs. Centennial catalogs: Northern Chile

ISC-GEMCentennial

Chile

Pacific

Ocean

Chile

Pacific

Ocean

Storchak et al (submitted)

Bolivia Bolivia

How were these results achieved? Uniform relocationsPre-1918 Centennial locations events were simply adopted from reliable

sourcesIn ISC-GEM, all but 1900-1903 shocks were relocated based on arrival time data

7Storchak et al (submitted)

Centennial ISC-GEM

Uniform magnitudes

ISC-GEM uses a unified MW magnitude scale, originating from just four sources

Ms, mb, mB, Mw, UK, others Storchak et al (submitted)

ISC-GEM Catalog: The signature of plate tectonics

km

continentalcollision

subduction

Rifting

subduction

Backarcspreading

(Colored byfault type)

Newlydiscoveredactive faultsin Myanmar

Sieh et al(in preparation)

ISC-GEM Seismic Catalog

(orange quakes are shallow,

blue are deep)

T H A I L A N D

B A N G L A -D E S H M Y A N M A R

A N D A M A N S

H I M A L A Y A S

GEM FaultedEarth

KelvinBerryman

(GNS Science)Principal

Investigator

A new tool for geologists to upload their faults to GEM

K. Berryman, A. Chistophersen, N. Litchfield, and GEM IT staff

Seismic source interpretation and upload tool

K. Berryman, A. Chistophersen, N. Litchfield, and GEM IT staff

GEM Faulted Earth: Uploaded fault traces and regions so far covered

NewZealand

U.S. JapanHimalayas

Australia

Alaska

Oceanic transforms

Hawaii

K. Berryman, A. Chistophersen, K. Haller, Y. Awata, N. Litchfield, P. Tapponnier, and K. Sieh

Europe

South America

Indonesia

Middle East

Central Asia

Middle EastStill to come:

Japan

Taiwan

Java

Tonga

Aleutians

NewGuinea

Philippines

Fault depth (km)

Sumatra

GEM Faulted Earth 40,000 km of

subductionzones

SLAB 1.0of Hayes &

Wald (2010)

GEM Large HistoricalEarthquake Catalog

AD 1000-1900

Paola Albiniand

Roger Musson,(in prep.)

GEM Large HistoricalEarthquake Catalog

AD 1000-1900

Paola Albiniand

Roger Musson,(in prep.)

GEM Large HistoricalEarthquake Catalog

AD 1000-1900

Paola Albiniand

Roger Musson,(in prep.)

Indonesia: GEM Historical Catalog has 12 times more quakes than NOAA

NOAA Catalog: 6 earthquakes GEM Catalog: 75 earthquakes

NOAA = National Geophysical Data Center/ World Data Service Significant Earthquake Database

Java

Myanmar

Paola Albini and Roger Musson (in prep.)

1900‐2009

Instrumental and historical catalogs complement each othe

Istanbul

GEM Historical CatalogM≥7 during AD 1000‐1900

1900‐2009 Istanbul

Instrumental and historical catalogs complement each othe

Instrumental and historical catalogs complement each other

Instrumental and historical catalogs complement each other

GEM Historical CatalogM≥7 during AD 1000‐1900

White et al., 2004  Ms  = 7.60

Zúñiga et al., 1997  Mw = 8.10

Nishenko & Singh, 1987 (13 MDPs)

ISC‐GEM Mw = 7.69 ± 0.68

Engdahl & Villa., 2002 Mw = 7.40 

Abe & Noguchi, 1983 Ms  = 7.70

Calibration issues: 1903 M~7.7 Mexico-Chiapas

M. Stucchi(in prep.)

500 km

Avni et al., 2002 (macroseismic)

Ben-Menahem et al., 1976 ML = 6.2

ISC-GEM Mw = 6.29 ±0.21

Location uncertainties: 1927 Jericho earthquake

Max Stucchi (in prep.)

Amman

Jerusalem

Tel Aviv

Who needs a Global Strain Rate Model?

Quake rate Strain rate

Wasatchfault

Cas‐cadia

If all accumulating strain were released seismically, the quake rateshould be proportional to strain rate

2000-2011 GPS velocities used by Kreemer et alfor the GEM Strain Rate Model

Gutenberg-Richter a-value from declusteredANSS catalog (Arnaud Mignan, ETH Zurich)

WesternUnited States

GEM Global Strain Rate Model reveals earthquake potential and active faults

Warmer colorsindicate highstrain andthus highquakerates

Kreemeret al (in prep.)

4,000 velocitiesin 2004 model,

20,000 inGEM’s

Canada

SouthAmerica

Mexico Caribbean

Alaska

U.S.

GEM Global Strain Rate Model reveals earthquake potential and active faults

Warmer colorsindicate highstrain andthus highquakerates

Kreemeret al (in prep.)

China

TaiwanIndia

Java

Japan

Sumatra

Iran

Philippines

Tibet

IndianOcean

New Guinea

East    Africanrift

4,000 velocitiesin 2004 model,

20,000 inGEM’s

GEM Strain Rate Model and ISC-GEM Catalog across Eurasia

Strain rate (nanostrain/yr)

Strain rate and large 20th century earthquakes are correlated

M≥6 earthquakes

GEORGIA

IRAN

TUNISIATIBET

CRETE

KYRGYZSTAN

INDIA

ITALY

PAKISTAN

JORDAN

ALGERIA

SERBIA

TURKEY

But strain exceeds seismicity in Himalayas, Tehran, Baku, North Anatolian fault, Greece

ISAREL

Iran: GEM Strain Rate Model and ISC-GEM Catalog

Strain rate (nanostrain/yr)

I R A N

Tehran

Dubai

Tabriz

Baku

C A S P I A N

A Z E R B A I J A N

M≥6 earthquakes

1.5 million

2.1 million

12.0 million

1.5 million

Population

Kreemer(in prep.)

Shiraz

Tehran

Northern Italy

Kreemer, in prep.

Pavia PaviaEmilia

Romagna

ISC‐GEM quakes

Western Turkey

Istanbul

Istanbul

Izmir

Bursa

Kreemer, in prep.

ISC‐GEM quakes

Northern Philippines

Manila

ISC‐GEM quakes

Baguio

Kreemer, in prep.

Chile and ArgentinaKreemer, in prep.

Santiago

ISC‐GEM quakes

Santiago

2011 LandscanPopulation

density

1900-2009 ISC-GEMEarthquake Catalog

Santiago

Global Strain Rate Model helps regional modelers hunt for local faults

Global Strain Rate Model helps regional modelers hunt for local faults

SHARE Model Faults

Global Strain Rate Model helps regional modelers hunt for local faults

Because inadequate fault data is perhaps the greatest weakness of hazard models

Because inadequate fault data is perhaps the greatest weakness of hazard models

GEM’s response to seismic hazard debate

Yan Y. Kagan, David D. Jackson, and Robert J. Geller

Mark W. Stirling

Seth Stein, Robert Geller, and Mian Liu

September/October 2012

2012

John AdamsCanada NatlHaz Model

John AdamsCanada NatlHaz Model

Mark StirlingNZ Natl Haz

(Powell co‐PI)

Oliver BoydCentral US Haz

Model

MarcoPaganiGEM

MarcoPaganiGEM

Seth Stein, PSHA critic

Alex AllmannMunich Re

Laura PeruzzaEuropean Models

Laura PeruzzaEuropean Models

Bring warring parties together on a mountain top for 3 days to develop new strategies, and to agree on tests of seismic hazard assessment

Mark  Leonard,  Australia Natl Haz Model

Ray DurrheimSo.  Africa Model

Anke FriederichEuropeangeology

Anke FriederichEuropeangeology

USGS Powell Center Workshops: Harnessing the community

Ned FieldCalif HazModel

Mark PetersenUS Nat’l Haz Model

DavidJackson

PSHA critic

GraemeWeatherill, GEM

Danijel SchorlemmerGEM Testing and 

EvaluationFacility

Martin KäserMunich ReMartin KäserMunich Re

Mark StirlingNZ Natl Haz(Powell co‐PI)

Mark StirlingNZ Natl Haz(Powell co‐PI)

Morgan PageCalif HazModel

Gavin HayesSubduction

zones

USGS Powell Center Workshops: Harnessing the community

• Build a testable global earthquake activity rate model using smoothed seismicity and GEM strain rate

• Abandon assignments of ‘maximum earthquake magnitude’ for a scientifically defensible alternative

• Test post‐1996 ground motions againstthe 1996 US Natl Seismic Hazard model

Powell Center Groups: Essential projects

More quakes

Less quakes

Forecast quake rate (log scale)

Bird, Jackson, Kagan, Kreemerand Weatherill (in prep.)

GEM Earthquake Activity Rate (GEAR) retrospective forecast for post-2005 M≥5.75

quakes

Best forecast is from 37.5% GEM Strain Rate Model and 62.5% pre-2005 seismic

catalog

Forecast quake rate (log scale)

More quakes

Less quakes

GEM Earthquake Activity Rate (GEAR) retrospective forecast for post-2005 M≥5.75

quakes

Best forecast is from 37.5% GEM Strain Rate Model and 62.5% pre-2005 seismic

catalogBird, Jackson, Kagan, Kreemerand Weatherill (in prep.)

GEM Strain Rate Model and ISC‐GEM CatalogVolkan Sevilgen (USGS)

Some of the GEM team

Strain Rate

Kreemer, in prep.

Standard deviation of the Strain Rate

Kreemer, in prep.

Signal-to-noise ratio of the strain rate

Kreemer, in prep.

Dilatation (red) and contraction (blue) rates

Kreemer, in prep.

Greece and Crete

Kreemer, in prep.

Athens

AthensGulf of Corinth

ISC‐GEM quakes

Regional Examples

Kreemer, in prep.

ISC‐GEM quakes

Regional Examples

Kreemer, in prep.

ISC‐GEM quakes

Regional Examples

Kreemer, in prep.

Regional Examples

Kreemer, in prep.

Earthquake potential at millennial, century, and decade scales

Number of studies

Paola Albini (INGV Milan) and Roger Musson (British Geological Survey), Principal Investigators

GEM Large Historical Earthquake Catalog: 832 M≥7 quakes during AD 1000-1900

Magnitude

Paola Albini (INGV Milan) and Roger Musson (British Geological Survey), Principal Investigators

GEM Large Historical Earthquake Catalog: 832 M≥7 quakes during AD 1000-1900

Earthquake potential from millennial, century, and decade record

11 eqs in NOAA Catalogue vs 20 eqs in GLHE Catalogue

India

Tibet

Pakistan

Himalayas: GEM Catalog has twice the quakes of the NOAA Catalog

Regional Examples

Kreemer, in prep.

Regional Examples

Kreemer, in prep.

GEM Earthquake Activity Rate ModelBird, Jackson, Kagan, Kreemer & Weatherill (in prep.)

Stephen Young, Endurance Re: “Data Quality wasidentified as a serious issue in 2011. The Tohokuevent had not been fully considered in the event set,leaving decided gaps in knowledge.”From the Font Line, Bermuda Reinsurance (2012)

Stephen Young, Endurance Re: “Data Quality wasidentified as a serious issue in 2011. The Tohokuevent had not been fully considered in the event set,leaving decided gaps in knowledge.”From the Font Line, Bermuda Reinsurance (2012)

Winning blend: 62.5% catalog / 37.5% strain

Mixing parameter, aPure strainrate

Pure seismiccatalog

Thus far, the best predictors of future quakesare past quakes and strain rate

Inform

ation score (binary bits per quake) 

GEM Earthquake Activity Rate (GEAR) experiments find ‘seismic gap theory’

(next quakes in areas of high strain and fewest past quakes) fails

Bird, Jackson, Kagan, Kreemer & Weatherill (in prep.)

Internal outline‣ Themes‣ Difficulty of inferring future quakes from past quakes‣ Potential to prioritize global seismic threat if data and methods are uniform‣ Potential of testable PSHA if it is global and as uniform as possible

‣ Data‣ GEM Faulted Earth‣ GEM Historical earthquake catalog‣ ISC‐GEM Instrumental quake catalog‣ GEM Strain Rate Model‣ Powell process: Collaborative, open, problem‐solving‣ GEAR

‣ Landing‣ In the earth sciences, data trumps all, and so… ‣ The GC datasets are a gift to science, commerce, and humanity