32 research outputs found
Ricostruzione geologica tridimensionale della stratigrafia tardo-quaternaria nel sottosuolo di Ferrara
This work is aimed at the reconstruction of the upper Quaternary depositional architecture, below
the urban area of Ferrara, in northern Italy. The study area is part of the lower alluvial plain of the
Po and Reno rivers and is therefore dominate by fluvial channel sands, levee sands-silts, and interchannel
depression mud. The research was focused on the reconstruction of a digital geological
model of the sedimentary bodies buried in the first 35 m under the topographic surface. The study
units accumulated through Holocene and late Pleistocene times. The research work is based on the
analysis of a rich data set, derived from about 2,000 subsurface investigations, consisting of
continuous coring, penetration tests (including CPTU and SCPTU), and water wells stratigraphy.
The subsurface modelling was achieved through both the conceptual interpretation of surface and
subsurface information and the computerized geostatistic interpolation of digitalized data. The
digital interpolation overcame the large heterogeneity of the data set into a homogeneous statistical
and conceptual framework, through the use of a time and economic efficient work protocol. The
research work achieved the reconstruction of the environmental evolution of the area, from the last
glacial maximum time up to the present. The large climatic and eustatic fluctuations of the
Quaternary largely influenced the environmental evolution and sedimentary dynamics of the area.
During the last sea-level lowstand, a large body of synglacial river sands accumulated into the
research area, under middle alluvial plain conditions. During phases of the eustatic rising, a thick
alluvial plain body aggraded in the southern portion of the study area, fed by Apennines derived
rivers, whereas non depositional condition persisted on the northern structural high. The maximum
transgression was matched with the widespread sedimentation of fresh water marsh muds. During
the highstand times, sands accumulated into both the Po and Reno channels, and mud into the
adjacent interfluvial depressions. The research work demonstrated the great role played by the
compressive deformation of this portion of the seismic active Apennines Foredeep Basin in the
shaping of the depositional architecture. The sedimentary successions accumulated onto the
anticline crests are much thinner than those sedimented into the syncline areas. The stratigraphic
interpretation of the subsurface data can improve the geotechnical and hydrogeological work and
support an improved seismic danger mitigation of an area significantly affected by the May 2012
earthquakes
Seasonal changes in dry matter yield from Karst pastures as influenced by morphoclimatic features
Pastures are strongly affected by local environmental variables in terms of their species richness, plant composition and herbage production. A multi-site monitoring study was conducted over three years to investigate the influence of morphoclimatic factors on the seasonal variations in dry matter (DM) yield from Karst pastures. Seven sites located on the Italian and Slovenian Karst regions were investigated that differed in terms of their geological and geomorphological features, as well as their soil types. At each site, the daily DM yield (kg ha-1 d-1) was determined using Corral-Fenlon method which permits to simulate herbage utilization from grazing herds. The morphoclimatic features were also analysed, with the aim to evaluate the link between seasonal DM yield and geomorphological and environmental factors. Generalized non-linear mixed models were built to study the observed seasonal variations in DM yield, using day of the year (DOY), growing degree days (GDD), and cumulative rainfall. Furthermore, environmental descriptors were included in the model in order to evaluate their effects on DM yield. The seasonal variations in yield showed two growing periods (spring and late summer), which were described by Gaussian curves. For the spring growing period, the model improved when the interaction between soil granulometry and growing degree days corresponding to the curve peak was taken into account. This confirms the influence of soil type and air temperature on pasture yield. For the late summer growing period, the interaction between the sand classes and the number of rainy days from the beginning of the period to the peak of the curve improved the model. The curve parameters of our models are correlated with environmental descriptors depending on the lithology and particle size of soils. The results are essential for the optimization of pasture management and avoiding degradation due to over- or under-grazing
Liquefaction source layer for sand blows induced by the 2016 megathrust earthquake (Mw 7.8) in Ecuador (Boca de Briceño)
Numerous sand boils were generated in the alluvial plain at the mouth of the Rio BriceËœno valley (Ecuador) during
the Mw 7.8 earthquake of April 2016. The area is characterized by a series of raised marine terraces formed as a
consequence of the rapid tectonic coastal uplift during the Quaternary. Boreholes and geotechnical investigations
were carried during post-earthquake surveys and for the purpose of mitigating the liquefaction effects. Five
lithological units were identified at a site of embankment, which represented continental-marine and transitional
sedimentation since the Last Glacial Maximum. A comprehensive study of texture and petrographic composition
of sand boils has been performed and compared with sandy silts and silty sands of the buried sedimentary
sequence in order to identify the source levels for liquefaction. The petrographic components, in particular the
low content of bioclasts and carbonate fragments of the sand boils, allow to pinpoint a source layer made up of
fine-grained silty sands located between 2 and 4.5 m depth (Unit 2) whereas the deeper marine sands, richer in
bioclasts, were not involved. The results support the idea that earthquake-induced liquefaction phenomena are
not restricted to clean sands and well-sorted deposits, but may affect sand layers with significant amount of nonplastic
silt
Ricostruzione geologica tridimensionale della stratigrafia tardo-quaternaria nel sottosuolo di Ferrara
This work is aimed at the reconstruction of the upper Quaternary depositional architecture, below
the urban area of Ferrara, in northern Italy. The study area is part of the lower alluvial plain of the
Po and Reno rivers and is therefore dominate by fluvial channel sands, levee sands-silts, and interchannel
depression mud. The research was focused on the reconstruction of a digital geological
model of the sedimentary bodies buried in the first 35 m under the topographic surface. The study
units accumulated through Holocene and late Pleistocene times. The research work is based on the
analysis of a rich data set, derived from about 2,000 subsurface investigations, consisting of
continuous coring, penetration tests (including CPTU and SCPTU), and water wells stratigraphy.
The subsurface modelling was achieved through both the conceptual interpretation of surface and
subsurface information and the computerized geostatistic interpolation of digitalized data. The
digital interpolation overcame the large heterogeneity of the data set into a homogeneous statistical
and conceptual framework, through the use of a time and economic efficient work protocol. The
research work achieved the reconstruction of the environmental evolution of the area, from the last
glacial maximum time up to the present. The large climatic and eustatic fluctuations of the
Quaternary largely influenced the environmental evolution and sedimentary dynamics of the area.
During the last sea-level lowstand, a large body of synglacial river sands accumulated into the
research area, under middle alluvial plain conditions. During phases of the eustatic rising, a thick
alluvial plain body aggraded in the southern portion of the study area, fed by Apennines derived
rivers, whereas non depositional condition persisted on the northern structural high. The maximum
transgression was matched with the widespread sedimentation of fresh water marsh muds. During
the highstand times, sands accumulated into both the Po and Reno channels, and mud into the
adjacent interfluvial depressions. The research work demonstrated the great role played by the
compressive deformation of this portion of the seismic active Apennines Foredeep Basin in the
shaping of the depositional architecture. The sedimentary successions accumulated onto the
anticline crests are much thinner than those sedimented into the syncline areas. The stratigraphic
interpretation of the subsurface data can improve the geotechnical and hydrogeological work and
support an improved seismic danger mitigation of an area significantly affected by the May 2012
earthquakes
Banca dati e Shapefiles ArcGIS delle Mappe della Microzonazione Sismica della totalità del territorio del Comune di Mirabello (Provincia di Ferrara)
Banca dati e Shapefiles in ambiente ArcGIS per la Carta Geologica, Carta Geologico-Tecnica, Carta della microzonazione del rischio sismico, potenziale di amplificazione sismica e rischio di liquefazione del territorio del Comune di Mirabello
Banca Dati ArcGIS e Carte della Microzonazione Sismica del Comune di Sala Bolognese (Provincia di Bologna)
Data base e shapefiles Arcgis per la gestione di: Carta Geologica, Carta Geologico-Tecnica, Carta della microzonazione del rischio sismico, potenziale di amplificazione sismica e rischio di liquefazione del territorio del Comune di Sala Bolognese
Banca dei dati geologici e geotecnici di sottosuolo del terriotrio del Comune di Mirabello
Banca dati in ambiente ArgGIS di tutti i dati disponibili al novembre 2014 sul sottosuolo del Comune di Mirabello (Provincia di Ferrara), comprendente sondaggi stratigrafici, prove penetrometriche, indagini geofisiche, informatizzati con criteri congruenti con quelli elaborati dal Serivizio Geologico, Sismico e dei Suoli della Regione Emilia-Romagna. Stato del dato: pubblico
Report geologico per il sito della stazione sismica IT.SULP – Sulmona (AQ)
Istituto Nazionale di Geofisica e Vulcanologia (INGV)Submitted5T. Sismologia, geofisica e geologia per l'ingegneria sismic
Banca dati geologici di sottosuolo del Comune di Ferrara
Banca dati in ambiente ArgGIS di tutti i dati disponibili al novembre 2014 sul sottosuolo del Comune di Ferrara, comprendente sondaggi stratigrafici, prove penetrometriche, indagini geofisiche, informatizzati con criteri congruenti con quelli elaborati dal Serivizio Geologico, Sismico e dei Suoli della Regione Emilia-Romagna. Stato del dato: pubblico