225 research outputs found
Morphology of Salina offshore (Southern Tyrrhenian Sea)
In this paper, we present the first complete morphological map of the Salina offshore at a scale
of 1:100,000. The submarine flanks of the Salina edifice extend down to â650 to â1300 m, are
steep and characterized by an uneven morphology due to the presence of volcanic and erosivedepositional
features. The volcanic features cover âŒ30% of the submarine portion and include
volcanic cones and bedrock outcrops. The remaining âŒ70% is affected by a wide series of
erosive-depositional features. Among these, features related to Late Quaternary sea level
fluctuations comprise the insular shelf surrounding the island and overlying submarine
terraced depositional sequences. Mass-wasting features include landslide scars, channels, fanshaped
deposits and waveforms. The presented map provides useful insights for a better
understanding of the morphological evolution of the edific
Morphology of Lipari offshore (Southern Tyrrhenian Sea)
High-resolution multibeam bathymetry was recently collected around Lipari, the largest and
most densely populated island of the Aeolian Archipelago (Southern Tyrrhenian Sea). The
data were acquired within the context of marine geological studies performed in the area
over the last 10 years. We present the first detailed morphological map of the Lipari
offshore at 1:100,000 scale (Main Map). A rugged morphology characterizes the submarine
portions of Lipari volcano, reflecting both volcanic and erosive-depositional processes. The
volcanic features include cones, lava flows and bedrock outcrops. Erosive-depositional
features include an insular shelf topped by submarine depositional terraces related to LateQuaternary
sea-level fluctuations, as well as landslide scars, channelized features, fanshaped
deposits and wavy bedforms. The different distribution of volcanic and erosivedepositional
features on the various sectors of Lipari is mainly related to the older age of the
western flank with respect to the eastern one. The map also provides insights for a first
marine geohazard assessment of this active volcanic area
The first ultra-high resolution Digital Terrain Model of the shallow-water sector around Lipari Island (Aeolian Islands, Italy)
Very high resolution bathymetric map obtained through multibeam echosounders
data are crucial to generate accurate Digital Terrain Models
from which the morphological setting of active volcanic areas can be analyzed
in detail. Here we show and discuss the main results from the first
multibeam bathymetric survey performed in shallow-waters around the island
of Lipari, the largest and the most densely populated of the Aeolian
Islands (southern Italy). Data have been collected in the depth range of
0.1-150 m and complete the already existent high-resolution multibeam
bathymetry realized between 100 and 1300 m water depth. The new ultrahigh
resolution bathymetric maps at 0.1-0.5 m provide new insights on the
shallow seafloor of Lipari, allowing to detail a large spectrum of volcanic,
erosive-depositional and anthropic features. Moreover, the presented data
allow outlining the recent morphological evolution of the shallow coastal
sector of this active volcanic island, indicating the presence of potential
geo-hazard factors in shallow waters
First evidence of contourite drifts in the north-western sicilian active continental margin (Southern tyrrhenian sea)
We present the results of an integrated geomorphological and seismo-stratigraphic study based on high resolution marine data acquired in the north-western Sicilian continental margin. We document for the first time five contourite drifts (marked as EM1a, EM2b, EM2, EM3a, and EM3b), located in the continental slope at depths between ca. 400 and 1500 m. EM1a,b have been interpreted as elongated mounded drifts. EM1a,b are ca. 3 km long, 1.3 km wide, and have a maximum thickness of 36 m in their center that thins northwards, while EM1b is smaller with a thickness up to 24 m. They are internally characterized by mounded seismic packages dominated by continuous and parallel reflectors. EM2 is located in the upper slope at a depth of ca. 1470 m, and it is ca. 9.3 km long, more than 3.9 km wide, and has a maximum thickness of ca. 65 m. It consists of an internal aggradational stacking pattern with elongated mounded packages of continuous, moderate to high amplitude seismic reflectors. EM2 is internally composed by a mix of contourite deposits (Holocene) interbedded with turbiditic and/or mass flow deposits. EM1a,b and EM2 are deposited at the top of an erosional truncation aged at 11.5 ka, so they mostly formed during the Holocene. EM3a,b are ca. 16 km long, more than 6.7 km wide, and have a thickness up to 350 m. Both EM2 and EM3a,b have been interpreted as sheeted drift due to their morphology and seismic features. The spatial distribution of the contourite drifts suggests that the drifts are likely generated by the interaction of the LIW, and deep Tyrrhenian water (TDW) on the seafloor, playing an important role in the shaping this continental margin since the late Pleistocene-Holocene. The results may help to understand the deep oceanic processes affecting the north-western Sicilian continental margin
Do third-year mental health nursing students feel prepared to assess physical health?
Background The life expectancy for people with mental health issues is significantly lower than
the general population, however, their physical health needs are often unrecognised by health
professionals.
Aim To investigate whether third-year mental health nursing students are clinically prepared to
undertake a pre-defined set of physical health checks.
Method A 34-item questionnaire was completed by two cohorts of mental health nursing students
in their third and final year. Participants self-reported on their competence to assess a range of
physical health checks. 37 questionnaires were completed and analysed.
Findings Three groups emerged: group 1 â 100% of students self-declared competence in
assessments including temperature and pulse, group 2 â more than 50% of students self-declared
competence in assessments including urinalysis and pulse oximetry, and group 3 â less than 50%
of students self-declared competence in taking electrocardiograms and using the hydration
assessment tool.
Conclusion The student participants of this study were not adequately prepared to undertake a
complete range of physical health assessments for people with mental health issues
Morphology of the submerged Ferdinandea Island, the âNeverlandâ of the Sicily Channel (central Mediterranean Sea)
We present the bathy-morphological map at a scale of 1: 50,000 of the area around the submerged Ferdinandea Island, the âNeverlandâ of the Sicily Channel (central Mediterranean Sea). We investigate an area of 100 km2, between 10 and 350 m, which is part of a triangular morphological high, 360 km2 wide, representing the SE-wards prolongation of the Adventure Bank. The study is based on the morphometric analysis based on high resolution multibeam, and sub-bottom CHIRP profiles collected in 2015. The area around the remains of Ferdinandea Island is morphologically shaped by the interplay between volcanic, tectonic, fluid seepage, and oceanographic processes. Since the study area is considered a hot spot of biodiversity affected by maritime traffic (especially in Ferdinandea Channel) and hosting communication pipelines, this map provides insights both for habitat mapping purposes and preliminary marine geohazard assessment due to the occurrence of historically active submarine volcanoes, pockmarks, and mass transport deposits
Mid-to-late Holocene upper slope contourite deposits off Capo Vaticano (Mediterranean Sea): High-resolution record of contourite cyclicity, bottom current variability and sandy facies
none13noThe upper continental slope offshore Capo Vaticano (southern Tyrrhenian Sea) is characterized by a contourite depositional system with well-developed elongated sediment drifts. This system is related to a northward paleo-bottom current, similar to the present-day modified-Levantine Intermediate Water (modified-LIW) flowing from the Messina Strait. In this work, we show results from an integrated analysis of descriptive oceanography, high-resolution seismic profiles and core data (i.e., grain size, foraminiferal assemblages, tephrostratigraphy and AMS radiocarbon dating) collected from the crest and moat sectors of drift deposits. The studied succession formed since the mid Holocene, under the action of the modified-LIW and the stratigraphic architecture indicates an upslope migration of the moat and rather stable position of the crest sector. Grain-size features recorded from two sediment cores indicate the occurrence of a succession of complete bi-gradational sand-rich contourite sequences. Sandy facies were observed both as lag deposits formed in active moat channel and as coarser intervals of bi-gradational sequences forming drift deposits close to its crest. Their occurrence would highlight that upper slope environments impacted by intermediate water masses and proximal to sandy sources may represent favorable settings for accumulation of sandy sediment. The moat sector is characterized by a more complex stratigraphic record, where either moat sedimentation or lateral deposition of finer sediment occur, suggesting that further investigation is required to better understand this complex element of contourite systems. Based on available age information, some of the bi-gradational sequences probably formed during the Dark Age Cold Period, providing example of a small-scale cyclicity of contourite deposition, likely related to short-term (possibly multicentennial scale) fluctuations of the paleo modified-LIW. According to age constraints and analysis of foraminiferal assemblages, these fluctuations were likely governed by climate variations, with a weaker activity during warmer periods and faster currents during colder events.openMartorelli E., Bosman A., Casalbore D., Chiocci F., Conte A.M., Di Bella L., Ercilla G., Falcini F., Falco P., Frezza V., Gaglianone G., Giaccio B., Mancini M.Martorelli, E.; Bosman, A.; Casalbore, D.; Chiocci, F.; Conte, A. M.; Di Bella, L.; Ercilla, G.; Falcini, F.; Falco, P.; Frezza, V.; Gaglianone, G.; Giaccio, B.; Mancini, M
Anatomy and origin of authochthonous late Pleistocene forced regression deposits, east Coromandel inner shelf, New Zealand: implications for the development and definition of the regressive systems tract
High-resolution seismic reflection data from the east Coromandel coast, New Zealand, provide details of the sequence stratigraphy beneath an autochthonous, wave dominated inner shelf margin during the late Quaternary (0-140 ka). Since c. 1 Ma, the shelf has experienced limited subsidence and fluvial sediment input, producing a depositional regime characterised by extensive reworking of coastal and shelf sediments during glacio-eustatic sea-level fluctuations. It appears that only one complete fifth-order (c. 100 000 yr) depositional sequence is preserved beneath the inner shelf, the late Pleistocene Waihi Sequence, suggesting any earlier Quaternary sequences were mainly cannibalised into successively younger sequences. The predominantly Holocene-age Whangamata Sequence is also evident in seismic data and modern coastal deposits, and represents an incomplete depositional sequence in its early stages of formation. A prominent aspect of the sequence stratigraphy off parts of the east Coromandel coast is the presence of forced regressive deposits (FRDs) within the regressive systems tract (RST) of the late Pleistocene Waihi Sequence. The FRDs are interpreted to represent regressive barrier-shoreface sands that were sourced from erosion and onshore reworking of underlying Pleistocene sediments during the period of slow falling sea level from isotope stages 5 to 2 (c. 112-18 ka). The RST is volumetrically the most significant depositional component of the Waihi Sequence; the regressive deposits form a 15-20 m thick, sharp-based, tabular seismic unit that downsteps and progrades continuously across the inner shelf. The sequence boundary for the Waihi Sequence is placed at the most prominent, regionally correlative, and chronostratigraphically significant surface, namely an erosional unconformity characterised in many areas by large incised valleys that was generated above the RST. This unconformity is interpreted as a surface of maximum subaerial erosion generated during the last glacial lowstand (c. 18 ka). Although the base of the RST is associated with a prominent regressive surface of erosion, this is not used as the sequence boundary as it is highly diachronous and difficult to identify and correlate where FRDs are not developed. The previous highstand deposits are limited to subaerial barrier deposits preserved behind several modern Holocene barriers along the coast, while the transgressive systems tract is preserved locally as incised-valley fill deposits beneath the regressive surface of erosion at the base of the RST. Many documented late Pleistocene RSTs have been actively sourced from fluvial systems feeding the shelf and building basinward-thickening, often stacked wedges of FRDs, for which the name allochthonous FRDs is suggested. The Waihi Sequence RST is unusual in that it appears to have been sourced predominantly from reworking of underlying shelf sediments, and thus represents an autochthonous FRD. Autochthonous FRDs are also present on the Forster-Tuncurry shelf in southeast Australia, and may be a common feature in other shelf settings with low subsidence and low sediment supply rates, provided shelf gradients are not too steep, and an underlying source of unconsolidated shelf sediments is available to source FRDs. The preservation potential of such autochthonous FRDs in ancient deposits is probably low given that they are likely to be cannibalised during subsequent sea-level falls
Seismogenic faults, landslides, and associated tsunamis off southern Italy - Cruise No. M86/2, December 27, 2011 - January 17, 2012, Cartagena (Spain) - Brindisi (Italy)
Summary
The continental margins of southern Italy are located along converging plate boundaries, which
are affected by intense seismicity and volcanic activity. Most of the coastal areas experienced
severe earthquakes, landslides, and tsunamis in historical and/or modern times. The most
prominent example is the Messina earthquake of Dec. 28, 1908 (Ms=7.3; 80,000 casualties),
which was characterized by the worst tsunami Italy experienced in the historical time (~2000
casualties). It is, however, still unclear, whether this tsunami was triggered by a sudden vertical
movement along a major fault during the earthquake or as a result of a giant marine slide
initiated by the earthquake. The recurrence rates of major landslides and therefore the risk
associated with landslides is also unknown. Based on detailed bathymetric data sets collected by
Italian colleagues in the frame of the MaGIC Project (Marine Geohazards along the Italian
Coast), we collected seismic data (2D and 3D) and gravity cores in three working areas (The
Messina Straits, off Eastern Sicily, the Gioia Basin). A dense grid of new 2D-seismic data in the
Messina Straits will allow to map fault patterns in great detail. One interesting outcome in this
context is the identification of a set of normal faults striking in an EW-direction, which is almost
perpendicular to the previously postulated faults. This EW-striking faults seem to be active. The
area off eastern Sicily is characterized by numerous landslides and a complex deformation
pattern. A 3D-seismic data set has been collected during the cruise using the so called P-cable in
order to investigate these deformation patterns in detail. The new data will be the basis for a risk
assessment in the working areas
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