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The Pays rÎéééémoisin the eastern Paris Basin is an administrative area of 1394 km2; in the surroundings of Reims (France). Two main geological substrata are separated by the ÎééééÎle-de-France cuesta: the Tertiary substratum in the western part is composed of various types of geomaterials (clay, sandstone, limestone, burrstone), whereas the substratum in the eastern part is composed only of Cretaceous Chalk. A field survey in each communeof the Pays rÎééééÎémoisidentified 26 building materials documented in a Geographic Information System database (GIS-database) that includes information about them (lithology, petrographical and petrophysical data, weathering) and the corresponding buildings (e.g. town, georeferenced data, building type, position on the facade). The spatial analysis of the building materials’ distribution (Standard Deviational Ellipse) with GIS identifies their uses and the criteria established for the selection of the materials: availability, efficiency, workability and durability. Some lithologies were preferred for particular buildings or selected for their efficiency in specific positions. The study also defines the relation between the stones’ origin (local and non-local stones) and their application. This database is useful to establish stone replacement strategies in the Pays rÎééééÎéémois.

Reims Cathedral is a major monument in the NE of France originally built with local Lutetian limestone. The recent closure of the last quarries has made restoration using the same stone more complicated. The restoration stones used currently are Lutetian limestones from the centre of the Paris Basin (Saint-Pierre-Aigle and Saint-Maximin stones). Mapping of the Cathedral's façades confirmed the data from ancient manuscripts: Courville stone was the original building stone, but several other local stones from various quarries and beds were also used. As a follow-up to this mapping, Lutetian limestones from five disused quarries were sampled for petrophysical characterization tests: thin section analyses, porosimetry, capillary and drying kinetics. The petrophysical properties of the limestones showed differences between the two main local stone types (Ditrupalimestone and miliolids limestone) and also between the quarries. This study addresses the difficulty of selecting new stone for restoration. Should ancient quarries be re-opened? If so, which ones?

AbstractCathodoluminescence (CL) examination of Recent biogenic carbonates shows that they are often luminescent regardless of their mineralogical composition (calcite v. aragonite), habitat (marine v. fresh water), way of life (sessile v. vagile) or environment (hyper- v. hyposaline water). Thus, the presence of luminescence in biogenic particles is not a reliable indicator of diagenetic alteration as some authors have suggested. In addition, CL can reveal variations in the mineralogy of shell material (e.g. regenerated calcitic v. primary aragonitic) and can highlight growth-related structures. Manganese (Mn2+) is the most likely activator of this luminescence, and its content in the shells of benthic organisms seems to be linked to growth rate, ontogeny, open sea conditions, bathymetry and salinity. In neritic environments the Mn2+content and the CL of molluscs and foraminifera appear to increase with decreasing salinity. This study indicates that CL may be an important tool for the determination of environmental and ontogenetic parameters in biogenic carbonates in addition to its current use indiagenetic studies.