ABSTRACT: Environmental Issues in Urban Exploration: The Paris Example

DUVAL, BERNARD C., and PHILIPPE F. PICARD,* TOTAL, PARIS LA DEFENSE, FRANCE

An exploration permit comprising the city of Paris and its suburbs was awarded in December 1985 to an association of ELF, TOTAL, and BP. Surface geology and geothermal wells to the Middle Jurassic had already given information on the structural framework. There would be no need for a drilling location in the historic center of the city. Drilling had been carried out on the banks of the Seine without any major difficulty or nuisance. The main novelty was to acquire approximately 1000 km of seismic lines in dense urban area. Vibroseismic was selected. Several environmental issues had to be tackled, some related to surface and subsurface features: stability of old buildings, historical sites, former quarries filled through ages, and a complex underground network of pipes (gas, water) and lines (power, telephone). Some of the underground features superimposed since the nineteenth century were difficult to locate with accuracy. Various types of material and laying techniques had been used. Their sensitivity to vibrations had to be checked. A search through archives and some real size testing were undertaken. Minimizing obstruction to traffic and reducing noise were of major concern. Most of the survey was performed at night with power limitation to the vibrators. Finding sites to drill upholes was difficult. Exploration wells were drilled from temporarily available locations. Plans were made for production facilities. Residents in the area were informed through appropriate means. Careful planning and cooperation of the authorities and of the population resulted in a smooth campaign.

AAPG Search and Discovery Article #91012©1992 AAPG Annual Meeting, Calgary, Alberta, Canada, June 22-25, 1992 (2009)