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A critical review is conducted of a selection of paleoseismic works published on, or close to, metropolitan France over the last 30 years. The evolution of these works may be subdivided into three periods: dawn of French paleoseismic studies (≈1990–1995), beginning of a multidisciplinary paleoseismologic approach, and paleoseismic studies in the first decades of the 21st century. This review of the most interesting paleoseismic studies at nine trench sites indicates that it is often difficult to associate Quaternary surface deformations with a well-identified fault. However, these studies also provided important results demonstrating that even in regions of low seismicity, seismic ruptures can repeat on the same low slip rate fault, thus providing evidence that historical seismicity is not sufficient to assess seismic hazard in metropolitan France. Finally, recommendations are provided for future paleoseismic investigations in low-seismicity regions. [ABSTRACT FROM AUTHOR]

The French Institute for Radiation Protection and Nuclear Safety (IRSN), with the support of the Ministry of Environment, compiled a database (BDFA) to define and characterize known potentially active faults of metropolitan France. The general structure of BDFA is presented in this paper. BDFA reports to date 136 faults and represents a first step toward the implementation of seismic source models that would be used for both deterministic and probabilistic seismic hazard calculations. A robustness index was introduced, highlighting that less than 15% of the database is controlled by reasonably complete data sets. An example of transposing BDFA into a fault source model for PSHA (probabilistic seismic hazard analysis) calculation is presented for the Upper Rhine Graben (eastern France) and exploited in the companion paper (Chartier et al., 2017, hereafter Part 2) in order to illustrate ongoing challenges for probabilistic faultbased seismic hazard calculations. [ABSTRACT FROM AUTHOR]