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USGS · 70176706

Development of the Global Earthquake Model’s neotectonic fault database

Abstract

The Global Earthquake Model (GEM) aims to develop uniform, openly available, standards, datasets and tools for worldwide seismic risk assessment through global collaboration, transparent communication and adapting state-of-the-art science. GEM Faulted Earth (GFE) is one of GEM’s global hazard module projects. This paper describes GFE’s development of a modern neotectonic fault database and a unique graphical interface for the compilation of new fault data. A key design principle is that of an electronic field notebook for capturing observations a geologist would make about a fault. The database is designed to accommodate abundant as well as sparse fault observations. It features two layers, one for capturing neotectonic faults and fold observations, and the other to calculate potential earthquake fault sources from the observations. In order to test the flexibility of the database structure and to start a global compilation, five preexisting databases have been uploaded to the first layer and two to the second. In addition, the GFE project has characterised the world’s approximately 55,000 km of subduction interfaces in a globally consistent manner as a basis for generating earthquake event sets for inclusion in earthquake hazard and risk modelling. Following the subduction interface fault schema and including the trace attributes of the GFE database schema, the 2500-km-long frontal thrust fault system of the Himalaya has also been characterised. We propose the database structure to be used widely, so that neotectonic fault data can make a more complete and beneficial contribution to seismic hazard and risk characterisation globally.

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Annemarie Christophersen, Nicola Litchfield, Kelvin Berryman, Richard Thomas, Roberto Basili, Laura Wallace, William Ries, Gavin P. Hayes, Kathleen M. Haller, Toshikazu Yoshioka, Richard D. Koehler, Dan Clark, Monica Wolfson-Schwehr, Margaret S. Boettcher, Pilar Villamor, Nick Horspool, Teraphan Ornthammarath, Ramon Zuniga, Robert M. Langridge, Mark W. Stirling, Tatiana Goded, Carlos Costa, Robert Yeats. 2015-06-06. Development of the Global Earthquake Model’s neotectonic fault database. https://doi.org/10.1007/s11069-015-1831-6

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