Recent studies of the upper Kimmeridgian of the Boulonnais area (northernmost France) have provided a sequence-stratigraphical framework that is here used to help interpret variations in sedimentary organic matter (OM) content and composition in response to fluctuations in relative sea-level. The organic facies are characterised using a combination of palynofacies, bulk organic geochemistry (TOC, Rock Eval pyrolysis, and sulphur data), and the particlesize distribution of the total palynological residues. The organic facies show a good correlation with the sequence stratigraphy, exhibiting peak TOC, HI, total S and S org values in the lithofacies deposited around the two MFS. The palynofacies in these intervals is characterised by a high content of fluorescent, orange, marine AOM. There is a strong correlation between the orange AOM and the total and organic sulphur contents. Similar positive correlations between orange AOM and organic sulphur have previously been observed in the distal organic-rich sediments of the Kimmeridge Clay Formation of Dorset (lateral time equivalents of the Boulonnais facies), but there the sulphur contents are lower, indicating that organic sulphur content of orange AOM is not fixed, suggestive of preservation-related parallel but not intrinsically related trends. The S data can be used to estimate an apparent burial efficiency and hence the proportion of the primary productivity preserved; this allows a rough estimate of palaeoproductivity. Model calculations suggest that for a sulphide retention of 30-70% and uncompacted sedimentation rate estimates in the range 5-10 cm/ka, the mean palaeoproductivity was in the range 52-175 gC/m 2 /a (up to 6% of which was preserved). Thus, if the preservation is high, as is the case for MFS, the palaeoproductivity does not need to be above average for shelf waters to produce a given TOC.

Abstract. Following the earthquake of 12 January 2010 in the Port-au-Prince area, the Haitian government, in close cooperation with BRGM, the French geological Survey, decided to undertake a seismic microzonation study of the metropolitan area of the capital in order to take more fully into account the seismic risk in the urbanization and planning of the city under reconstruction. As the first step of the microzonation project, a geological study has been carried out. Deposits of Miocene and Pliocene formations in a marine environment have been identified. These deposits are affected by the Enriquillo-Plantain Garden N80 • E fault system and N110 • E faults. Tectonic observations and morphological analysis indicate Quaternary activity of several faults mapped in the area of Port-au-Prince. These faults have a N110 • trend and show a reverse-sinistral strike-slip motion. Moreover, on the basis of these geological results and of new topographical data, a hazard assessment of ground movements has been made. Along with the map of active faults, the hazard map of ground movements is an integral component of the seismic microzonation study.

Stable isotope (C and O) analyses were carried out on pedogenic nodules from carbonate-rich paleosols from early to middle Miocene strata in the Digne-Valensole foreland basin (southeast France). Paleosols from three sections corresponding to several paleoenvironments were sampled in order to investigate the local influence on the isotope record of the depositional sites: a deltaic floodplain (Châteauredon section, BCR), an inland floodplain (Saule Mort section, SM) and a shallow lacustrine system (Pont d’Aiguines section, PA). According to their biostratigraphy, they correspond to the same stratigraphic interval. Paleosols are regularly distributed along the three sections. They have developed either on floodplain alluvium or on palustrine carbonate mud. They are characterized by fersiallitic red soils with a calcic horizon, typical of a xeric soil moisture conditions with a marked seasonality. Carbonate nodules sampled at depths of 0.3 to 1 m below the preserved top soil are considered suitable for paleoecological interpretation. The cross-plot of the δ18O and δ13C values shows well-distributed data indicating that the pedogenic nodules were not affected by any major recrystallizations during burial. Their distribution indicates climate conditions similar to those of modern Mediterranean soils, characterized by carbonates precipitating from enriched meteoric water. A refined stratigraphic attribution of all the sections is based on the carbon isotope chemostratigraphy developed on the Châteauredon section by correlation with marine carbon isotope data [Bialkowski et al., 2006]. All sections extend from very early Aquitanian to middle Serravallian. No major hiatus was identified except for the one associated with a highly karstified surface in the Pont d’Aiguines section. The hiatus duration, estimated to 1 Ma, is interpreted as the record of some deformation at the front of the Digne thrust sheet during the Langhian. Most carbon isotope values are heavier than −8‰, suggesting a water-stressed C3 vegetation growing in a semi-arid environment. These semi-arid conditions are found in all sections during early Aquitanian and late Burdigalian to early Serravallian (Middle Miocene climatic optimum, MMCO), indicating similar environmental conditions between the coastal sites (BCR and PA sections) and the inland SM section. From middle Aquitanian to late Burdigalian, data from the coastal sites indicate typical C3 vegetation whereas xeric conditions characterized the inland site, suggesting distinct local ecosystems. The interpretation of the oxygen isotope record is more complex due to the different interactions during carbonate precipitation. In the early Aquitanian, the concomitant decrease in the pedogenic δ13C and δ18O isotope values is interpreted as a decrease of the water-stressed environmental conditions due either to a change in precipitation patterns resulting in low evaporation or to a fall in temperature. For the Langhian, the high δ13C values indicate xeric conditions throughout the area, and the high δ18O values at the coastal site suggest an increase in the combined effect of temperature and evaporation. Evidence of deformation related to the foreland basin evolution during this period is supported by the great differences in the oxygen isotope record of the different sections. The observed changes in the environmental conditions of the Digne-Valensole basin agree with the climate fluctuations identified on the basis of paleobotanical assemblages and mammal teeth isotope records from western European continental basins and of marine data. Our results show that a study of paleosols and the isotope composition of the pedogenic carbonate of the early to middle Miocene in the Digne-Valensole basin provide valuable information concerning the regional paleotopographic evolution of the foreland basin, as well as the distinct paleoecological systems that developed between the inland and the coastal sites and the regional paleoclimatic trends that correspond to those identified in other European continental basins. These reconstructions based on paleosols, the dry-end member of the climatic record, are complementary to those based on the paleofloras, mostly obtained from the wet-end member.

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This study presents the results of a palynological analysis (dinocysts, spores and pollen) that are discussed with those obtained from stable isotopes geochemistry (δ 13 C and δ 18 O) on Miocene coastal and continental deposits in the southern area of the Digne Valensole Basin. Palynology study has been conducted on dark levels while isotopic analysis was performed on paleosol carbonate nodules.Stratigraphic attributions based on palynology are restricted to dinoflagellate cysts associations as spore and pollen assemblages are scarcely identified. They confirm the stratigraphy based on the micromammal fossil sites and propose an Aquitanian to early Serravallian age. From a selection of ODP-DSDP sites, the marine δ 13 C chemostratigraphy shows several characteristic isotopic intervals. These were also identified on the continental signal from the paleosols.Stratigraphic interpretation from the isotopic continental signal is in good agreement with both palynological data and micromammal sites attributions. It can offer a high resolution correlation, a few 100 kyr when paleosols are frequent and δ 13 C fluctuations significant. The method puts also in evidence hiatuses (during middle Aquitanian and late Burdigalian) and precise the age of formations interbedded between micromammal sites.Regarding paleoenvironmental reconstruction, the palynological study is more efficient than isotopic data and shows a flora evolution from mesothermic riparian and coastal vegetation during Aquitanian/Burdigalian to herbaceous and more open vegetation during the Langhian period in association to a drier and warmer climate.This study brings also new insights on paleogeographic reconstructions. The studied area was located close to the sea coast during the lower Miocene. Marine incursions occurred during the middle Aquitanian and from late Burdigalian to early Serravallian. These are characterized by tidal facies as well as dinoflagellate cysts and benthic foraminifera occurrences. These marine incursions, better recorded in the eastern part of the Châteauredon Dome, argued for a northern or a southern connection with the Miocene sea in relation to the foreland basin geodynamic evolution. RESUMECette étude présente les résultats de la palynologie (kystes de dinoflagellés, spores et pollen) discutés avec ceux de la géochimie des isotopes stables (δ 13 C et δ 18 O) réalisée sur les séries côtières et continentales d'âge miocène dans la partie sud du bassin de Digne. L'étude palynologique a été réalisée sur des niveaux noirs et les analyses isotopiques sur les nodules carbonatés des paléo-sols.Les attributions stratigraphiques sont basées sur la palynologie établie à partir des associations de dinokystes et non sur les assemblages de spores et pollen, peu diversifiés. Elles confirment la stratigraphie établie d'après les sites fossilifères de micromammifères et proposent un âge Aquitanien à Serravallien inférieur. A partir d'une sélection de plusieurs sites ODP-DSDP, la chimiostratigraphie δ 13 C marine montre plusieurs intervalles isotop...