Search results for " deposits"
showing 10 items of 56 documents
Differenziazione e quantificazione dei carbonati litogenici e pedogenici di Gypsisuoli forestali attraverso l'analisi isotopica
2004
Gli autori riferiscono sui tipi e sui modelli di genesi dei carbonati dei suoli, attraverso l’uso degli isotopi del 13C. Lo studio è stato condotto in un’area dell’interno collinare argilloso siciliano, su suoli che evolvono sui depositi evaporitici della Serie Gessoso-Solfifera. Sono stati scelti cinque pedon su litotipi calcarei e non. I pedon sono stati descritti in campo e campionati secondo la sequenza degli orizzonti genetici; sui campioni di suolo sono state eseguite le seguenti analisi: tessitura, reazione, conducibilità elettrica, gesso, carbonio organico ed inorganico. Inoltre, parallelamente sono state eseguite le analisi isotopiche del carbonio organico ed inorganico. I risultat…
FACIES HETEROGENEITY AND SEDIMENTARY PROCESSES ALONG A TECTONICALLY-CONTROLLED CARBONATE SLOPE: A CASE STUDY FROM THE CRETACEOUS OF WESTERN SICILY (I…
2020
Accounting meets economics: towards an ‘accounting view’ of money.
2018
Questo studio pone le fondamenta dell’ “Approccio Contabile” (“Accounting View”) alla moneta. Sulla base dei principi di Ragioneria Generale riconosciuti internazionalmente, lo studio argomenta che le monete emesse dallo stato e dalla banca centrale non costituiscono debito e che nei regimi di riserva frazionaria soltanto una quota della moneta emessa dalle banche commerciali pu essere considerata quale debito. Lo studio chiarisce come il signoraggio associato all’emissione di queste monete debba essere contabilizzato nei bilanci delle istituzioni emittenti ed esamina le implicazioni di ci`o per la corretta comprensione della moneta. Il nuovo approccio fa luce su argomenti quali la vera nat…
Paleoenvironmental evolution of the Pliocene Villarroya Lake, northern Spain. A multidisciplinary approach
2002
The Pliocene Villarroya basin fill consists of lacustrine and alluvial deposits over 100 m thick. The lacustrine deposits, up to 30 m thick, comprise three sequences. The two lower sequences consist of profundal, laminated deposits formed by mostly terrigenous facies that are overlain by charophytic carbonates and varves. The uppermost, third sequence made up of massive bioturbated mudstones corresponds to a very shallow lacustrine-palustrine environment. Bulk mineralogy comprises carbonates, clay minerals, quartz and feldspars. The carbonates are: exogenic, biogenic calcite and biogenic aragonite. Biogenic calcite constitutes ostracod shells and charophyte stem encrustations, whereas arago…
Fault rate controls on carbonate gravity-flow deposits of the Liassic of Central High Atlas (Morocco).
2013
21 pages; International audience; The aim of this work is to describe and to explore linkages between fault activity and gravity-related sedimentary deposits during the early rifting of a carbonate depositional system. The study area, located at the southern edge of Central High Atlas (Morocco), hosts 900 m thick Liassic gravity-related sedimentary deposits, preserved at the hanging wall of one of the possibly inherited, reactivated Hercynian faults (Tizi n'Firest fault). This study documents gravity-flow deposits constrained by a highresolution biostratigraphic framework (ca. 100 ka). These gravity-flow deposits evolve over time. Unstratified conglomerate beds are limited to the Sinemurian…
New insights from recently migrated CROP multichannel seismic data at the outermost Calabrian arc accretionary wedge (Ionian sea)
2011
This study addresses selected aspects of the stratigraphic-structural setting of the outermost Calabrian Arc accretionary wedge and underlines relationships between structural development and Messinian evaporite stratigraphy through the analysis of re-processed CROP multichannel seismic reflection profiles. A detailed seismostratigraphic analysis, calibrated with P-velocities compiled by previous works, images a general bipartition of the Messinian evaporite deposits: the transparent «lower subunit» appears to have undergone ductile-flow deformation», with the development of salt-cored thrusting structures, and the layered «upper subunit» appears to be characterized by brittle deformation. …
Study of the high temperature behaviour of titanium alloy Ti6242S under complex atmospheres : aeronautical applications
2018
The use of titanium alloys in many applications (transport, energy, chemistry,...) allows significant weight savings in relation to the good mechanical properties/density ratio of these materials. Since titanium alloys are employed at high temperatures (T>500°C), their behavior in such conditions has to be studied in severe conditions in order to understand degradation mechanisms. Moreover, some specific conditions can be met during application, like thermal cycling, water vapour or presence of salts. These parameters are known to influence oxidation behavior of titanium alloys.In this thesis work, oxidation behavior of an aeronautics titanium alloy (Ti6242S) has been studied in air and moi…
Increasing understanding and confidence in THM simulations of engineered barrier systems
2020
Previous studies on the modelling of coupled thermo-hydro-mechanical (THM) processes in bentonite-based engineered barrier systems (EBSs) showed the sensitivity of the output quantities to changes in the input parameters. To investigate the effects of uncertainties on the modelling results, to improve the understanding of the coupled processes active in the repository near field and to gain in-depth understanding of model uncertainties of different codes, a sensitivity analysis and code comparison of EBS simulations was performed within the Task Force on Engineered Barrier Systems. The analysis included variations in material parameter values, boundary and initial conditions, considered phy…
Lacustrine sedimentation in the diapir-controlled Miocene Bicorb Basin, Eastern Spain
1998
The Miocene Bicorb Basin is a small elongated basin developed by normal faulting of a thick Jurassic–Cretaceous carbonate succession and subsequent diapirism of Upper Triassic mudstones and evaporites. The basin fill comprises a sequence over 650 m thick formed by two units. The lower, alluvial unit consists of a complex alternation of conglomerates, sandstones, mudstones, and minor lacustrine limestones. The upper unit comprises marginal alluvial and lacustrine deposits in which seven lacustrine facies associations have been distinguished. The inner lacustrine deposits comprise mudstones and carbonates with minor evaporitic deposits. At the northeast and southwest basin edges, alluvial inp…
Petrography and high-resolution geochemical records of Lower Jurassic manganese-rich deposits from Monte Mangart, Julian Alps
2016
Deposits with unusually high Mn contents sampled at Monte Mangart in the Julian Alps include organic-rich marlstone and black shale with interbedded manganoan and siliceous limestone, which were deposited during the early Toarcian Oceanic Anoxic Event. Mn enrichment during that period has been related to global sea-level change coincident with increasing subsidence rate. The formation of Fe-Mn nodules, marking a hardground at the base of the Monte Mangart section, seems to be triggered by release of Mn from remote hydrothermal vents into a region of relatively elevated submarine topography where oxidizing conditions prevailed. However, very high Mn contents in carbonate phases above the har…