Search results for "bepress|Physical Sciences and Mathematics|Earth Sciences"
showing 10 items of 2332 documents
Reconstitutions paléoenvironnementales des bassins finicarbonifèresà permiens en contexte tardi-orogénique (N-E duMassif central) : implications palé…
2021
National audience; Les bassins intracontinentaux fini-carbonifères à permiens du nord-est du Massifcentral s'inscrivent dans la dynamique fini-paléozoïque, dans le cadre de l'extensiontardi- orogénique de la chaîne varisque.Les bassins d'Autun et de Decize-La Machine (région de Lucenay-lès-Aix, ensubsurface) ont fait l'objet d'une étude visant à mieux caractériser les environnementsde dépôt sédimentaires, basée principalement sur des données de forages carottés. Lescarottes ont été décrites en termes d'associations de faciès, permettant de déterminerles environnements de dépôt et leur évolution au cours du temps.Dans le bassin d'Autun, les dépôts silicoclastiques grossiers témoignent de dép…
A revision of the structure and stratigraphy of pre-Green Tuff ignimbrites at Pantelleria (Strait of Sicily)
2013
International audience; At Pantelleria, peralkaline silicic magmas were erupted across a range of eruptive typologies and magnitudes: pyroclastic flows, Plinian to strombolian pumice fallout and lava flows. In this paper we focus on the intermediate cycle of eruptive activity which is bracketed by ignimbrite units slightly older than the two caldera collapses which marked the volcanological activity of the island. This age interval (180-85 ka) was punctuated by six ignimbrite-forming eruptions (silicic and variably peralkaline) for a cumulative erupted magma volume of approximately 6 km3 dense rock equivalent. Based on new 40Ar/39Ar (Na,K)-feldspar ages and petrographic data, we propose an …
Collections universitaires et Paléontologie.
2010
À partir de l’exemple du programme Trans’Tyfipal®, mené par le laboratoire Biogéosciences de l’université de Bourgogne et qui a pour objectif d’inventorier tous les spécimens types paléontologiques conservés en France, l’auteur montre comment l’un des grands défis pour les musées universitaires est de se développer en bonne harmonie entre la recherche, la formation et la valorisation. From the example of the Trans’tyfipal® programme, led by the Biogeosciences laboratory at Burgundy University, and which aims at listing all the Paleontological type specimens kept in France, the author explains how one of the major challenges for university museums is to encourage research, training and prom…
Guano-related phosphate-rich minerals in European caves
2019
International audience; Guano is a typical deposit found in caves derived from the excretions of bats and in minor cases of birds. These organic deposits decompose and form a series of acid fluids and gases that can interact with the minerals, sediments, and rocks present in the cave. Over sixty phosphates are known and described from caves, but guano decay also often leads to the formation of nitrates and sulfates. In this study twenty-two European caves were investigated for their guano-related secondary minerals. Using various analytical techniques, seventeen phosphates, along with one sulfate (gypsum), were recognized as secondary products of guano decay. Among those minerals, some are …
Dynamique spatio-temporelle d’un événement extrême froid : impact de la circulation atmosphérique sur les basses températures en Bourgogne viticole.
2020
During April 2019 France experienced several frost events that caused extensive damage to almost all of its winegrowing regions. In Bourgogne-Franche-Comté the frost effects were very punctual and spatially diffused, the greatest damage being observed in the early bud breaking winegrowing sub-regions of Saône-et-Loire and the south of the Côte de Beaune. This study focuses on the multi-scalar analysis of the spring frost event underwent during the night between the 4th and 5th of April on a vineyard plot located in the Hautes Côtes de Beaune appellation. The analysis highlights the impact of local parameters (topography, surface discontinuity, etc.) on the spatio-temporal structuring of tem…
Sekcija "Arheologu un etnogrāfu pētījumi Latvijā 2018. – 2020. gadā" : Tēžu krājums
2021
Krājumā apkopotas 2021. gada 11. martā Latvijas Universitātes 79. starptautiskās zinātniskās konferences ietvaros Latvijas Universitātes Latvijas vēstures institūta organizētās sekcijas “Arheologu un etnogrāfu pētījumi Latvijā 2018. – 2020. gadā” nolasīto referātu tēzes. Tēzēs atspoguļojas LU Latvijas vēstures institūta, LU Vēstures un filozofijas fakultātes un Latvijas Nacionālā vēstures muzeja arheologu ieguldījums arheoloģiskā mantojuma un senvēstures aktuālu jautājumu izpētē. Tēzēs ietvertās atziņas balstītas padziļinātos, starpdisciplināros pētījumos, tās atspoguļo jaunu tēmu un arheoloģiskā materiāla interpretāciju meklējumus, kā arī arheoloģisko pieminekļu apzināšanas un izrakumu met…
Transport of Antarctic stratospheric strongly dehydrated air into the troposphere observed during the HALO-ESMVal campaign 2012
2015
Abstract. Dehydration in the Antarctic winter stratosphere is a well-known phenomenon that is annually observed by satellites and occasionally observed by balloon-borne measurements. However, in situ measurements of dehydrated air masses in the Antarctic vortex are very rare. Here, we present detailed observations with the in situ and GLORIA remote sensing instrument payload aboard the German aircraft HALO. Strongly dehydrated air masses down to 1.6 ppmv of water vapor were observed as far north as 47° S in an altitude between 12 and 13 km in the lowermost stratosphere. The dehydration can be traced back to individual ice formation events above the Antarctic Peninsula and Plateau, where ice…
Raman Investigations to Identify Corallium rubrum in Iron Age Jewelry and Ornaments
2016
International audience; During the Central European Iron Age, more specifically between 600 and 100 BC, red precious corals (Corallium rubrum) became very popular in many regions, often associated with the so-called (early) Celts. Red corals are ideally suited to investigate several key questions of Iron Age research, like trade patterns or social and economic structures. While it is fairly easy to distinguish modern C. rubrum from bone, ivory or shells, archaeologists are confronted with ancient, hence altered, artifacts. Due to ageing processes, archaeological corals lose their intensive red color and shiny surface and can easily be confused with these other light colored materials. We pr…
Surcotes, tempêtes et risque d’inondation le long du littoral belge : variabilité contemporaine et future (1950-2100)
2010
6 pages; International audience; A l’échelle quotidienne, la hauteur des surcotes à Ostende est quasi-linéairement corrélée à la pressionatmosphérique de surface (PSM) sur la Mer Baltique. Les plus fortes surcotes s’y produisent quand une dépression restestationnaire plusieurs jours sur la Scandinavie synchrone à un renforcement de l’anticyclone des Açores. Cette géographiebarométrique favorise la genèse des forts vents d’afflux de nord-ouest dans la partie sud de la Mer du Nord. Un modèle derégression linéaire permet de simuler de façon robuste la variabilité interannuelle des fortes surcotes à Ostende de 1950 à2000 avec (i) la PSM autour de la Mer Baltique et (ii) le gradient barométrique…
Determinants of the interannual relationships between remote sensed photosynthetic activity and rainfall in tropical Africa
2007
International audience; The response of photosynthetic activity to interannual rainfall variations in Africa South of the Sahara is examined using 20 years (1981-2000) of Normalised Difference Vegetation Index (NDVI) AVHRR data. Linear correlations and regressions were computed between annual NDVI and annual rainfall at a 0.5° latitude/longitude resolution, based on two gridded precipitation datasets (Climate Prediction Center Merged Analysis of Precipitation [CMAP] and Climatic Research Unit [CRU]). The spatial patterns were then examined to detect how they relate to the mean annual rainfall amounts, land-cover types as from the Global Land Cover 2000 data set, soil properties and soil typ…