Action 2.3 : Site effects in historical databases

Identify site effects in historical databases

Motivations

In this study, we propose to quantify and map the local site effects in Metropolitan France from the analysis of macroseismic observations. The main challenge consists here in extracting workable signatures of site-effects from a qualitative and sometimes sparse macroseismic dataset, especially in early historical times. We will use Intensity Data Point (IDP) from the SISFRANCE database (EDF-IRSN-BRGM) that covers an approximate 1000 years period up to present. In particular, we aim at extracting information over the whole territory, and to extend the analysis beyond the most seismically active areas actually covered by the instrumental catalogue.

Program of research

We aim at delivering a map of “historical site effects”. The rationale consists in searching for systematic biases in the spatial distribution of IDPs which could be related to potential local site effects. To reach this goal, we will develop two different methods: first, a grid-search approach, and second, an analysis on residuals based on a pre-selected macroseismic attenuation law.

Rognes

Organization

  • Type: Internship, Research study
  • Collaboration: EDF
  • Status: In progress (started 2018)