Search results for "Sediment"

Structural highs formation and their relationship to sedimentary basins in the north Sicily continental margin (southern Tyrrhenian Sea): implication…

2005

Two high-penetration seismic profiles across the continental margin of north Sicily (southern Tyrrhenian Sea) have been interpreted to construct a crustal section across the margin and to provide a three-dimensional perspective on the upper crustal setting of the Solunto High and its structural relationships with the adjacent Cefalù Basin. Crystalline rocks of the Kabilian-Calabrian Units (KCU) are recognized in the Solunto High region and farther to the north. The KCU body is tectonically superimposed onto sedimentary rocks pertaining to the Sicilian-Maghrebian Units (SMU) and the Solunto High corresponds to the thrust sheet culmination. Its occurrence in the Solunto High demonstrates that…

Dye-tracer technique for rill flows by velocity profile measurements

2020

Abstract Water flow on hillslope soil surface supplies energy which is required to detach soil particles, to transport and deposit sediments, therefore flow velocity is a key variable related to hillslope hydrodinamics of soil erosion processes. Among the different methods available for measuring velocity of shallow interrill and rill flow, the trace technique is widely used. Trace technique is applied by adding a material (salt, magnetic material, water isotope, floating object) and then measuring the speed of the material to travel a known distance from the injection point. When flow velocity is measured using a dye-tracing method, the mean velocity is calculated by multiplying the measur…

Forearc carbon sink reduces long-term volatile recycling into the mantle

2019

Carbon and other volatiles in the form of gases, fluids or mineral phases are transported from Earth's surface into the mantle at convergent margins, where the oceanic crust subducts beneath the continental crust. The efficiency of this transfer has profound implications for the nature and scale of geochemical heterogeneities in Earth's deep mantle and shallow crustal reservoirs, as well as Earth's oxidation state. However, the proportions of volatiles released from the forearc and backarc are not well constrained compared to fluxes from the volcanic arc front. Here we use helium and carbon isotope data from deeply sourced springs along two cross-arc transects to show that about 91 per cent…

Modificazioni recenti della linea di costa connesse con l’azione antropica: esempi dalla Sicilia.

2008

Planktonic foraminifera in ODP Hole 160-963A

2006

New faunal and floral records from Ocean Drilling Project Hole 963A, resolved at ?80-year spacing, provide evidence of suborbital scale climate variability in the central Mediterranean Sea throughout Marine Isotope Stage (MIS) 5. Cold events in the central Mediterranean Sea, indicated by low abundances of warm species and high abundances of cold species, are also evident in a planktonic foraminifera paleoclimatic curve. They have been linked to NGRIP Greenland ice core “C” events and appear correlative with similar sub-millennial climate fluctuations identified in the North Atlantic region and in the Alboran Basin (Westernmost Mediterranean). Low-resolution benthic and planktonic Oxygen Iso…

Near Real-Time Modelling of Regional Scale Soil Erosion Using AVHRR and METEOSAT Data: A Tool for Monitoring the Impact of Sediment Yield on the Biod…

2005

List of Contributors. Preface. 1. Spatial Modelling of the Terrestrial Environment: The Coupling of Remote Sensing with Spatial Models (Richard E.J. Kelly, Nicholas A. Drake and Stuart L. Barr). PART I: HYDROLOGICAL APPLICATIONS. Editorial: Spatial Modelling in Hydrology (Richard E.J. Kelly). 2. Modelling Ice Sheet Dynamics with the Aid of Satellite Derived Topography (Jonathan L. Bamber). 3. Using Remote Sensing and Spatial Models to Monitor Snow Depth and Snow Water Equivalent (Richard E. J. Kelly, Alfred T. C. Chang, James L. Foster and Dorothy K. Hall). 4. Using Coupled Land Surface and Microwave Emission Models to Address Issues in Satellite--Based Estimates of Soil Moisture (Eleanor J…

Anomalous soil CO 2 degassing in relation to faults and eruptive fissures on Mount Etna (Sicily, Italy)

1998

The relationships between soil gas emissions and both tectonic and volcano-tectonic structures on Mt. Etna have been studied. The investigation consisted of soil CO2 flux measurements along traverses orthogonal to the main faults and eruptive fissures of the volcano. Anomalous levels of soil degassing were found mainly in coincidence with faults, whereas only 49% of the eruptive fissures were found to produce elevated CO2 soil fluxes. This result suggests that only zones of strain are able to channel deep gases to the surface. According to this hypothesis, several previously unknown structures are suggested. Based on our geochemical data, new structural maps of different areas of Etna are p…

2019

Although sediments of small boreal humic lakes are important carbon stores and greenhouse gas sources, the composition and structuring mechanisms of their microbial communities have remained understudied. We analyzed the vertical profiles of microbial biomass indicators (PLFAs, DNA and RNA) and the bacterial and archaeal community composition (sequencing of 16S rRNA gene amplicons and qPCR of mcrA) in sediment cores collected from a typical small boreal lake. While microbial biomass decreased with sediment depth, viable microbes (RNA and PLFA) were present all through the profiles. The vertical stratification patterns of the bacterial and archaeal communities resembled those in marine sedim…

The onset of the Messinian salinity crisis: Insights from Cyprus sections.

2009

International audience

EVOLUZIONE DIAGENETICA DELLE SUCCESSIONI PANORMIDI DEL LIMITE TRIASSICO/GIURASSICO

Lo studio sedimentologico e stratigrafico di alcune sezioni del Triassico Superiore-Giurassico Inferiore del dominio Panormide (Sicilia), ha contribuito all’elaborazione di un dataset che consente di avanzare nuove considerazioni sulla complessa evoluzione di questo dominio paleogeografico in prossimità del limite T/J. Sono stati studiati in dettaglio tre principali settori lungo la porzione nord-occidentale della Sicilia, dai Monti di San Vito alle Madonie, attraverso i Monti di Palermo. Nel settore più occidentale presso Monte Sparagio (penisola di Capo San Vito), l’analisi delle microfacies ha consentito di posizionare il limite T/J all’interno di una spessa successione di cicli peritida…