High resolution seismic prospection of old gypsum mines - evaluation of detection possibilities

Bogdan Piwakowski (1) , Jean-Marc Watelet (2) , David Moreaux (1) , Khalid Sbai (1)

1 Laboratoire de Physique des Vibrations et d'Acoustique (UMR 9929)
2 INERIS - Institut National de l'Environnement Industriel et des Risques

The aim of this work is to evalute the location and detection possibilities of the old Underground gypsum mines, appearing in the region of Paris, and being now unexploited, which represents a real danger both for population and building activities. The experiments were conducted in the site affected recently by serious accidents, caused by ground collapses. They included the application of the high resolution seismic reflection, microgravimetry and resistivity methods. The results obtained were tested by the drilling. The positions of the researched galleries were generally unknown and their occurence was only suspected due to the presence ground-collapse (GC) areas caused by the natural collapse of a cavity. Some of the GCs were observed directiy at the surface, the others were detected by means of the comparison of the old and recent aerial photographs. shows the general geological data of this site and the locations ofthe seisnüc profiles S2,S3,S4 considered in this report . The seismic data was recorded using the 100 Hz geophones and the silenced "betsy gun" as a source (designed in laboratory). The closest offset had been individually adapted, based on the approach of the Optimum offset window.

Domaines: Sciences de l'environnement

Bogdan Piwakowski, Jean-Marc Watelet, David Moreaux, Khalid Sbai. High resolution seismic prospection of old gypsum mines - evaluation of detection possibilities. 2. Meeting Environmental & Engineering Geophysic, Sep 1996, Nantes, France. pp.149-152. ⟨ineris-00971967⟩