State and church in France: regulation and negotiation

In France the distinction between the secular and religious domains is the result of a slow evolutionary process of secularization over a period of two centuries. A key element was the law of separation between churches and State in 1905. Secularization also produced a pluralistic socio-cultural system, which permits an increase in religious supply, issued from outside or inside existent churches. The religious landscape became complex due to the growth of certain groups. Nowadays, efforts to regulate Muslim communities are leading towards a new tendency of state control of religious activities in two fields, namely places of worship and school activities. Religious plurality is recognized by the State in the name of the freedom of beliefs. Private organizations are used for the public practice of religion and easily obtain places of worship. However, this has necessitated a large number of regional or local arrangements. In the name of the freedom of thought, the school system of the Republic is ensured by public schools, or by Catholic or Jewish schools, subject to strict public control. In this matter, there is only minimal tolerance of other denominations.

Uplift and denudation history at low-elevation passive margins: Insights from morphostratigraphic analysis in the SE Armorican Massif along the French Atlantic margin

Like other low-elevation passive margins, the French Atlantic margin is characterized by a gradual topographic transition from the coast to low-altitude interior plains or plateaus. Here we propose a morphostratigraphic analysis to constrain long-term landscape evolution and denudation rates, through the characterization of palaeotopographies and related palaeoweatherings in an area restricted to the southeast Armorican Massif. Two regional-scale palaeosurfaces are recognized: (i) the Infraliassic palaeosurface, the truncated weathering profiles of which are sealed by Liassic marine deposits; (ii) the Eocene palaeosurface, underlain by thick kaolinite- and iron-rich palaeosaprolites and by siliceous duricrusts (silcretes). Quantitative constraints on large-scale tectonic uplift and long-term denudation are obtained from these morphostratigraphic markers. Mean uplift and denudation rates calculated on post-Eocene times range between 0.5 and 2 m.Ma^-1. These low values imply high landscape stability of the inland margin over most of the Cenozoic.     

Remobilisation of deep Na-Cl waters by a regional flow system in the Alps: Case study of Saint-Gervais-les-Bains (France)

The hydrothermal system of Saint-Gervais-les-Bains, France is located in a south western low-elevation point of the Aiguilles Rouges crystalline Massif. The crystalline rocks are not directly outcropping in the studied area but certainly exist beyond 300 m depth. Uprising waters are pumped from two different aquifers below the Quaternary deposits of the Bon Nant Valley. In the Lower Trias-Permian aquifer crossed by De Mey boreholes (27–36 °C), the ascending Na-SO₄ and high-Cl thermal water from the basement (4.8 g/L) is mostly mixed by a Ca-SO₄ and low-Cl cold water circulating in the autochthonous cover of the Aiguilles Rouges Basement. The origin of the saline thermal water probably results from infiltration and circulation in the basement until it reaches deep thrust faults with leaching of residual brines or fluid inclusions at depth (Cl/Br molar ratio lower than 655). The dissolution of Triassic halite (Cl/Br > 1000) is not possible at Saint-Gervais-les-Bains because the Triassic cold waters have a low-Cl concentration (< 20 mg/L). Water–rock interactions occur during the upflow via north–south strike-slip faults in the basement and later on in the autochthonous cover. For the De Mey Est borehole, gypsum dissolution is occurring with cationic exchanges involving Na, as well as low-temperature Mg dissolution from dolomite in the Triassic formations. The aquifer of imbricated structures (Upper-Middle Trias) crossed by the Lépinay well (39 °C) contains thermal waters, which are strongly mixed with a low-Cl water, where gypsum dissolution also occurs. The infiltration area for the thermal end-member is in the range 1700–2100 m, close to the Lavey-les-Bains hydrothermal system corresponding to the Aiguilles Rouges Massif. For the Ca-SO₄ and low-Cl end-member, the infiltration area is lower (1100–1300 m) showing circulation from the Mont Joly Massif. The geothermometry method indicates a reservoir temperature of probably up to 65 °C but not exceeding 100 °C.     

A revision of the ammonite faunas of the type Cenomanian. i. Introduction,ancyloceratina

This paper forms the first part of a revision of the ammonite faunas of the Cenomanian stratotype in the environs of Le Mans, Sarthe, France. The history of research on ammonites in the area is briefly noted, as is the lithostratigraphy. The systematics of the heteromorph ammonites (Ancyloceratina) is described, and the following taxa documented: Hamites simplex d'Orbigny, Sciponoceras baculoides (Mantell), Sciponoceras gracile (Shumard), Anisoceras plicatile (J. Sowerby), A. aff. plicatile, Idiohamites alternatus vectensis Spath, I. ellipticus radiatus Spath, Hypoturrilites gravesianus (d'Orbigny), H. tuberculatus (Bosc), H. mantelli (Sharpe), H. sp., Neostlingoceras carcitanense (Matheron), N. aff. carcitanense, Turrilites costatus Lamarck, T. acutus Passy, T. scheuchzerianus (Bosc), T. boerssumensis Schlüter, Mariella dorsetensis (Spath), M. cenomanensis (Schlüter), M. group of cenomanensis (Schlüter)-lewesiensis (Spath), M. spp., M. (Plesioturrilites) sp., Scaphites equalis J. Sowerby, S. obliquus J. Sowerby, S.(?) sp., and S. sp. juv.     

Identification of an underfilled foreland basin system in the Upper Devonian of the Central Pyrenees: implications for the Hercynian orogeny

A foreland basin succession has been identified in the Frasnian of the Central Pyrenees. This succession comprises a carbonate-dominated transgressive system which recorded the cratonward migration of the foreland basin subsidence, and siliciclastic depocenters which recorded the progression of the thrust-fold deformation. The foreland basin system has always been maintained in deep-marine environments, i.e., at an underfilled depositional state. It was associated with a thrust wedge which descended toward a deep-marine hinterland, i.e., with a type of orogenic wedge usually related to subduction zones. The Frasnian foreland basin system differs from the one known in the Carboniferous which evolved to overfilled depositional state and was associated with a thrust wedge rising toward a mountainous hinterland. Consequently, the Hercynian orogeny in the Pyrenees seems to result first, from a Frasnian thrusting controlled by a subduction zone located north of the Pyrenees, and second, from a Carboniferous thrusting controlled by the surrection of a frontal thrust belt in the Pyrenees. The association of underfilled foreland basin systems and hinterland-dipping thrust wedges, as exemplified in the Frasnian of the Pyrenees, can be interpreted as illustrative of the initial stages of thrust-wedge growth in deep-marine settings.     

Impact des crues sur les bilans sédimentaires de chenaux secondaires de la Loire moyenne (France)

Volumes of sediments eroded and deposited during floods were quantified in a vegetated secondary channel of the Loire River at the study site of Bréhémont (France). The topographic survey highlights the temporal variability in filling of secondary channels. Upstream riffle of secondary channels governs sedimentary supply. In these channels, sediments show a by-passing in the lower parts and an accretion in the higher vegetated areas. The asymmetrical morphology is reinforced during both intense and moderate floods. Sedimentary accretion in the vegetated areas leads progressively to channel narrowing. To cite this article: S. Rodrigues et al., C. R. Geoscience 337 (2005).     

Longues séries d'insolation homogénéisées en France

Prior to have long-term sunshine-duration series, data rescue effort has to be engaged. Eighteen series have been homogenized over the period 1931–2000. These series complete the set of diagnoses on climate change at a regional scale, confirm part of the diagnosis established for the temperatures, and offer new tracks for the mechanisms of climate change. To cite this article: J.-M. Moisselin, C. Canellas, C. R. Geoscience 337 (2005).     

Characterisation of the seismological pattern in a slowly deforming intraplate region: Central and western France

We analyzed the seismicity of central and western France, using historical data, a compilation of all recorded earthquakes from 1962 to 2002 (4574 events, relocated), and all published focal mechanisms (119 focal solutions). The aim is to understand what are the causes of earthquakes and stress accumulation in a slowly deforming intraplate region. The distribution of earthquakes and focal mechanisms is first correlated with recognized faults, geological structures and tomographic images. Then, in order to better understand the distribution of hypocenters and seek deeper crustal sources for stress accumulation, Euler solutions are computed from the available Bouguer anomaly data. The analysis of the obtained pattern for heat flow values, provides a better understanding of the concentration of seismicity in some particular zones.Two different behaviors of this slowly deforming intraplate region are evidenced. One is linked to the presence of a hot spot under the Massif Central, the other to reactivation of the Hercynian structural heritage. Our results highlight that several possible sources for earthquake clustering can be invoked in central–western France.     

Découverte de structures périglaciaires (sand-wedges et composite-wedges) sur le site de stockage de déchets radioactifs de l'Aube (France)

Since 1990, a dense network of subvertical cracks has been observed at the upper part of the Albian sands of the site of radioactive waste storage operated by ANDRA. New studies carried out in 1999 during enlargement of the site of Soulaines and in 2003 on the nearby TFA site highlighted an especially well-developed network of periglacial features that are mainly of the sand-wedge type (subvertical stratified infill). These observations demonstrate the periglacial origin of these cracks, which are mainly superimposed on a dense network of former tectonic extension joints, and that rapidly disappear at the top of the underlying clays. In addition, these observations currently represent the only example of a large sand-wedge network developed during the Last Glacial in northern France. To cite this article: P. Antoine et al., C. R. Geoscience 337 (2005).