Taiwan is located at an active plate boundary and prone to earthquake hazards. To evaluate the island's seismic risk, the Taiwan Earthquake Model (TEM) project, supported by the Ministry of Sciences and Technology, evaluates earthquake hazard, risk, and related social and economic impact models for Taiwan through multidisciplinary collaboration. One of the major tasks of TEM is to construct a complete and updated seismogenic structure database for Taiwan to assess future seismic hazards. Toward this end, we have combined information from pre-existing databases and data obtained from new analyses to build an updated and digitized three-dimensional seismogenic structure map for Taiwan. Thirty-eight on-land active seismogenic structures are identified. For detailed information of individual structures such as their long-term slip rates and potential recurrence intervals, we collected data from existing publications, as well as calculated from results of our own field surveys and investigations. We hope this updated database would become a significant constraint for seismic hazard assessment calculations in Taiwan, and would provide important information for engineers and hazard mitigation agencies.

To provide information towards understanding Taiwan's earthquake hazard and risk, the multidisciplinary Taiwan Earthquake Model (TEM) project, supported by the Ministry of Sciences and Technology, had prepared and published a first version of seismic hazard assessment maps of Taiwan in 2016, together with an on-land seismogenic structure database of the island. In the years following the publication of this first version, we have constructed an updated version of this database. Seven structures were identified and added to the database. Based on additional information, we have also updated the structural parameters of four existing structures, as well as systematically updated the parameters of all structures to include more complete parameter uncertainties. This update of the database represents the most up-to-date information of seismogenic structures in Taiwan, and would provide better constraints for future seismic hazard assessment and mitigation studies.

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Accurate building inventories are essential for city planning and disaster risk management. Traditionally generated via census or selected small surveys, these suffer from data quality and/or resolution. High-resolution satellite imagery with object segmentation provides an effective alternative, readily capturing large extents. This study develops a highly automated building extraction methodology for location-based building exposure data from high (0.5 m) resolution satellite stereo imagery. The development relied on Taipei test areas covering 13.5 km2 before application to the megacity of Jakarta. Of the captured Taipei buildings, 48.8% are at one-to-one extraction, improving to 71.9% for larger buildings with total floor area >8000 m2, and to 99% when tightly-spaced building clusters are further included. Mean absolute error in extracted footprint area is 16% for these larger buildings. The extraction parameters are tuned for Jakarta buildings using small test areas before covering Jakarta's 643 km2 with over 1.247 million buildings extracted.

Frequent high seismic activities occur in Taiwan due to fast plate motions. According to the historical records the most destructive earthquakes in Taiwan were caused mainly by inland active faults. The Central Geological Survey (CGS) of Taiwan has published active fault maps in Taiwan since 1998. There are 33 active faults noted in the 2012 active fault map. After the Chi-Chi earthquake, CGS launched a series of projects to investigate the details to better understand each active fault in Taiwan. This article collected this data to develop active fault parameters and referred to certain experiences from Japan and the United States to establish a methodology for earthquake probability assessment via active faults. We consider the active faults in Central Taiwan as a good example to present the earthquake probability assessment process and results. The appropriate "probability model" was used to estimate the conditional probability where M ≥ 6.5 and M ≥ 7.0 earthquakes. Our result shows that the highest earthquake probability for M ≥ 6.5 earthquake occurring in 30, 50, and 100 years in Central Taiwan is the Tachia-Changhua fault system. Conversely, the lowest earthquake probability is the Chelungpu fault. The goal of our research is to calculate the earthquake probability of the 33 active faults in Taiwan. The active fault parameters are important information that can be applied in the following seismic hazard analysis and seismic simulation.