GEM Faulted Earth. A Global Active Fault and Fault Source Database

Transcription

1 GEM Faulted Earth A Global Active Fault and Fault Source Database Marco Pagani on behalf of GEM Faulted Earth Kelvin Berryman, Carlos Costa, Kerry Sieh Nicola Litchfield, Annemarie Christophersen

2 THIS PRESENTATION Uniform and open standards to calculate and communicate earthquake risk worldwide Some background on GEM GEM Faulted Earth Why GEM Faulted Earth? The Consortium Tasks and Deliverables The Database The plans for Africa Figure: Views of the Earth, the African Rift Valley, 2006 by Christoph Hormann

3 SOME BACKGROUND ON GEM GEM, the Global Earthquake Model, is a global collaboration that brings together state-ofthe-art science, national, regional and international organizations and individuals with the aim to build a uniform, independent standard to calculate and communicate earthquake risk worldwide

4 SOME BACKGROUND ON GEM Seismic Hazard: Five global components 1. Global Historical Catalogue and Database 2. Global Instrumental Earthquake Catalogue 3. Global Active Faults and Fault Source Database 4. Global Geodetic Strain Rate Model 5. Global Ground Motion Prediction Equations Figure: The Rift Valley by zedaway.com

5 WHY ARE ACTIVE FAULTS IMORTANT? Even faults with plate boundary rates of motion can be quiescent for significant periods of time using earthquake catalogues alone can seriously overlook future earthquake locations Therefore if seismic source regions are not built around fault mapping then the hazard and risk can be overly smoothed and seriously underestimated near faults. Fault data captures data on infrequent but large events that are often incomplete in historical catalogues Fault data provide an alternative option for earthquake model testing

6 WHY GEM FAULTED EARTH? Within the scope of GEM a Request for Proposal was released for the construction of a uniform global active fault and seismic source database with a common set of strategies, standards and formats, to be placed in the public domain. One international consortium that responded to the call was that led by principal investigators Kelvin Berryman (GNS Science, New Zealand), Kerry Sieh (EOS, Singapore) and Carlos Costa (UNSL, Argentina). In January 2010 the proposal was selected by GEM s Governing Board. The name of the project is GEM Faulted Earth. Budget: 450,000 Euro Duration: 24 months

7 THE GEM FAULTED EARTH CONSORTIUM Principal investigators: There are principal investigators Kelvin Berryman (GNS Science, New Zealand) Kerry Sieh (EOS, Singapore) Carlos Costa (UNSL, Argentina) Project management: Annemarie Christophersen (GNS Science, New Zealand) IT development: GNS Science, New Zealand, in close collaboration with the GEM model facility Regional Faulting leaders: Between regional fault leaders will contribute national and regional active fault coverages to the global database. These researchers are often linked to national institutions. Gaps in data will be covered by involving regional faulting teams and by literature survey. Science Review Board: The work that is being carried out, is overseen and reviewed by a board consisting of 10+ international leaders in active fault studies.

8 GEM FAULTED EARTH MORE BACKGROUND Data and researchers are global Data are site specific The project will produce a database with two fundamental layers: - an active fault layer containing site data the observational data - a fault source layer containing parameters required for PSHA The fault source layer is considered an initial strawman to be improved via integration and collaboration with other GEM (database) projects The project will progress in close collaboration with past, present, and new regional active fault and seismic source database projects such as the ILP databases, ReSeis in Central America, FAUST, SHARE, EMME, SEA, national programmes (e.g. Japan, USA, New Zealand, China), with GEM MF, and with other global and regional seismicity and geodesy projects. Success will depend crucially on contributions from a large number of scientists worldwide

9 GEM FAULTED EARTH TASKS AND DELIVERABLES T1 Task: Inventory existing fault databases Identify features to include in the GEM global database July 10 T2 Task: Design and build the GEM Faulted Earth database Layer (1) Active fault and fold database. Layer (2) A Seismic Source database IT structure due Dec 10 Completed T3 Task: Populating fault and seismic source layers T3a Task: Populating the Faults and Folds layer - existing databases due June 11 T3b Task: Enter seismic source databases and upload national seismic source existing databases due June 11, other regions due Dec 11 T3d Task: Enter SLAB 1.0 sources for subduction zones - due June 11 Completed; now doing only minor editorial changes T4 Task: Web portal for geologist upload of active fault trace and seismic source data - due Feb 12 Already under development as data compilation tool; an usability workshop was held in December T5 Task: Regional collaborators to build a database from the literature or imagery T5.1 New fault data due Feb 12 T5.2 New fault data interpreted as seismic sources due May 12 T6 Task: Dissemination due June 12 T6.1 Book, Active Faults of the World submitted to press T6.2 Final report GEM Faulted Earth Database uploaded to GEM website T6.3 GEM Faulted Earth database software made available to all database managers T6.4 Encourage contributors to publish and authors to contribute to GEM Faulted Earth database

10 GEM FAULTED EARTH TASK 1 and 2 T1 Task: Inventory existing fault databases Identify features to include in the GEM global database July 10 Completed Our inventory included: INGV Database of Individual Seismogenic Sources (DISS) USGS Quaternary Faults and Folds Database AIST RIO-DB Active Fault Database of Japan Map and Database of Quaternary Deformation for Andean Countries GNS New Zealand Active Faults Database Taiwan Active Fault Database Afghanistan Fault Database Database of oceanic ridges, transforms, and diffuse deformation zones Subduction zones T2 Task: Design and build the GEM Faulted Earth database Layer (1) Active fault and fold database. Layer (2) A Seismic Source database IT structure due Dec 10 Completed; now doing only minor editorial changes The following slide shows a schema of the database.

11 GEM FAULTED EARTH: THE DATABASE Folds Fault Sources Faults

12 GEM FAULTED EARTH: THE DATABASE Neotectonic faults: Summary table Observations Neotectonic faults are geological faults (fracture planes along which one side moves relative to the other) which contribute to seismic hazard The definition of the timeframe of activity (neotectonic period) will vary globally, ideally being long enough to capture several earthquake cycles. In practice this may include definitions such as the current tectonic regime (several million years) in low strain areas and the Late Pleistocene (125,000 years) in high strain areas.

13 GEM FAULTED EARTH: THE DATABASE Neotectonic faults: Summary table Neotectonic faults are described by detailed spatial data (the trace of the fault on the ground, including inferred traces where the fault is concealed), geometry parameters (strike, dip, dip direction, rake etc), parameters describing past movement and activity (slip type, slip rate, displacement, last event etc), and point data (locations or sites where parameters have been constrained). Observations Interpretations

14 GEM FAULTED EARTH: THE DATABASE

15 WEB PORTAL FOR UPLOAD OF ACTIVE FAULT

16 WEB PORTAL FOR UPLOAD OF ACTIVE FAULT

17 WEB PORTAL FOR UPLOAD OF ACTIVE FAULT

18 GEM FAULTED EARTH PLANS FOR AFRICA Establish one or more working groups Hold one or more training workshops to demonstrate the use of the data compilation software, provide assistance in compiling data, get feedback on possible improvement / additional functionalities perhaps required Lakes of the African Rift Valley, photo by NASA