China Active Faults Database and its web system

Abstract. Active faults are potential destructive earthquake sources and also the most serious strips of earthquake disasters in the future. Studies and investigations of active faults are necessary for earthquake hazard reduction. This study presents a nation-scale database of the active faults for China and its adjacent regions along with associated web-based query system. This database is an updated version of the active faults data included in the “Seismotectonic Map of China and its Adjacent Regions (1:4 000 000),” which is one of the four essential maps of the mandatory Chinese standard GB/T 18306-2015 Seismic Ground Motion Parameter Zonation Maps of China. The data update and integration are based on the latest 20-year region-scale active fault survey data (1:250 000 – 1:50 000). Those data include geophysical probing, drill logging, offset-landform measuring and sample dating, as well as geometric and kinematic parameters of exposed and blind faults, paleo-earthquake sequences, and recurrence intervals, and have been obtained and analyzed using the same technical standard framework and reviewed by expert panels in the field and laboratory. The database can be interrogated using a Web Geographic Information System (GIS) application, which provides browsing, inquiring, analyzing, and downloading functions on a web browser. The system also publishes the Open Geospatial Consortium (OGC) Web Feature Service and OGC Web Map Service of active fault data. Users can add map layers and download fault data in the OGC-compliant GIS software for further analyses via these services. The Chinese government, research institutions, and companies have widely used the active faults data from the previous versions of the Database. The database is available at https://doi.org/10.12031/activefault.china.400.2022.db (Xu, 2022) and via the Web System (CEFIS (V2), 2023; CAFD WFS). It is downloadable through diverse platforms and clients as introduced in Sections 4.3.2 and 4.4.