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This paper presents and discusses new geochronological and petrological data on a suite of calc-alkaline plutons composed predominantly of diorites and tonalites from the West Massif Central. Their petrochemical fingerprints are compatible with partial melting of a hydrous mantle wedge followed by fractional crystallization of amphibole and plagioclase before final emplacement between 5 and 8 kbar within the continental upper plate of a subduction system. In situ U-Pb zircon dating on tonalites yields a fairly narrow age range of 365−354 Ma (including uncertainties) for igneous crystallization. These calc-alkaline plutons imply active margin magmatism near the Devonian-Carboniferous boundary and are contemporaneous with the back-arc magmatism and HP metamorphism as dated by recent studies. However, such isolated igneous bodies do not form a transcrustal magmatic arc but rather represent dispersed plutons emplaced within less than 30 Myr when all data from the Variscan belt of France are considered. In Limousin, they intrude migmatitic paragneisses and retrogressed eclogites from the Upper Gneiss Unit (UGU), suggesting that the high pressure rocks were already exhumed at 19−30 km depth before 365 Ma. Moreover, the diorites and tonalites are never found within units below the UGU. It therefore suggests that these tectono-metamorphic units of the Western French Massif Central were piled up after 354 Ma. Altogether these results support the monocyclic model for Variscan geodynamics in the French Massif Central, with the transition between oceanic subduction and continental collision taking place between Upper Devonian and Lower Carboniferous.

The estimation of wall thermal properties through an inverse problem procedure enables to increase the reliability of the model predictions for building energy efficiency. Nevertheless, it requires defining an experimental campaign to obtain in situ observations for existing buildings. The quality of the estimated parameter strongly depends on the quality of the experimental data used for the parameter identification. In other words, there is a close relation between the experiment design and the precision of the retrieved parameters. The design of experiments enables to search for the optimal measurement plan. It ensures the highest precision of the parameter to be estimated. For in situ measurement in buildings, the design of experiments seeks to answer the following questions: How many sensors do we need? What is the sensor position in the wall? The optimal experiment design methodology enables us to answer those questions. The unknown parameter is the thermal conductivity of wall façade model considering two-dimensional heat transfer induced by time and space varying boundary conditions. [ABSTRACT FROM AUTHOR]