DTM-based morphometry of the Palinuro seamount (Eastern Tyrrhenian Sea): Geomorphological and volcanological implications

We present a high resolution DTM of the Palinuro Seamount (PS, Tyrrhenian Sea, Italy) resulting from the processing of multibeam swath bathymetry records acquired during the second leg of the “Aeolian 2007” cruise. PS consists of several superimposed volcanoes aligned along a N100°E strike and measures 55×25 km. The western and the central sectors result from the coalescence of collapse structures (calderas) with younger volcanic cones. The eastern sector reveals a more complex and articulated structure. In the central sector, a volcanic crater with a well-preserved rim not obliterated by erosional events suggests a volcanological rejuvenation of this sector. The presence of flat surfaces on the top of the seamount may be due to the formation of marine terraces during the last sea-level lowering. Lateral collapses on the northern and southern flanks of the seamount are probably related to slope instability, as suggested by the presence of steep slopes (25–40°). The main fault affecting PS strikes N65°E and shows a right lateral component of movement. E–W and N10°E striking faults are also present. Assuming that theN100°E deep-seated fault,which is responsible for theemplacement of PS,movedwith sinistral slips, we interpret the N65°E and the N10°E faults as right-lateral (second order) shear and left-lateral (third order) shear, respectively. Due to the particular location of the Palinuro Seamount, the data presented here allow us to better understand the volcanism and the geodynamic processes of the Tyrrhenian Sea

DTM-based morphometry of the Palinuro seamount (Eastern Tyrrhenian Sea): Geomorphological and volcanological implications

We present a high resolution DTM of the Palinuro Seamount (PS, Tyrrhenian Sea, Italy) resulting from the processing of multibeam swath bathymetry records acquired during the second leg of the “Aeolian 2007” cruise. PS consists of several superimposed volcanoes aligned along a N100°E strike and measures 55×25 km. The western and the central sectors result from the coalescence of collapse structures (calderas) with younger volcanic cones. The eastern sector reveals a more complex and articulated structure. In the central sector, a volcanic crater with a well-preserved rim not obliterated by erosional events suggests a volcanological rejuvenation of this sector. The presence of flat surfaces on the top of the seamount may be due to the formation of marine terraces during the last sea-level lowering. Lateral collapses on the northern and southern flanks of the seamount are probably related to slope instability, as suggested by the presence of steep slopes (25–40°). The main fault affecting PS strikes N65°E and shows a right lateral component of movement. E–W and N10°E striking faults are also present. Assuming that theN100°E deep-seated fault,which is responsible for theemplacement of PS,movedwith sinistral slips, we interpret the N65°E and the N10°E faults as right-lateral (second order) shear and left-lateral (third order) shear, respectively. Due to the particular location of the Palinuro Seamount, the data presented here allow us to better understand the volcanism and the geodynamic processes of the Tyrrhenian Sea

Integrated stratigraphic reconstruction for the last 80 kyr in a deep sector of the Sardinia Channel (Western Mediterranean)

A quantitative analysis of planktonic foraminifera, coupled with petrophysical and paleomagnetic measurements and 14C AMS calibrations, was carried out on a deep core recovered in the Sardinia Channel (Western Mediterranean Sea), during the CIESM Sub2 survey, providing an integrated stratigraphic time-framework over the last 80 kyr. Significant changes in the quantitative distribution of planktonic foraminifera allowed the identification of several eco-bioevents useful to accurately mark the boundaries of the eco-biozones widely recognised in the Western Mediterranean records and used for large scale correlations. Namely, 10 eco-biozones were identified based on the relative abundance of selected climate sensitive planktonic foraminiferal species. Sixteen codified eco-bioevents were correlated with the Alboran Sea planktonic foraminiferal data and four climatic global events (Sapropel S1, Younger Dryas, Greenland Isotope Interstadial 1, Greenland Isotope Stadial 2, Heinrich event H1-H6) were recognized. The eco-bioevents together with the 14C AMS calibrations allowed us to define an accurate age model, spanning between 2 and 83 kyr. The reliability of the age model was confirmed by comparing the colour reflectance (550 nm%) data of the studied record with the astronomically tuned record from the Ionian sea (ODP-Site 964). A mean sedimentation rate of about 7 cm/kyr included three turbidite event beds that were chronologically constrained within the relative low stand and lowering sea level phases of the MIS 4 and 3. The deep-sea sedimentary record includes a distinct tephra occurring at the base of the core which dates 78 ka cal. BP. The paleomagnetic data provide a well-defined record of the characteristic remanent magnetization that may be used to reconstruct the geomagnetic paleosecular variation for the Mediterranean back to 83 kyr

Integrated stratigraphic reconstruction for the last 80 kyr in a deep sector of the Sardinia Channel (Western Mediterranean)

A quantitative analysis of planktonic foraminifera, coupled with petrophysical and paleomagnetic measurements and 14C AMS calibrations, was carried out on a deep core recovered in the Sardinia Channel (Western Mediterranean Sea), during the CIESM Sub2 survey, providing an integrated stratigraphic time-framework over the last 80 kyr. Significant changes in the quantitative distribution of planktonic foraminifera allowed the identification of several eco-bioevents useful to accurately mark the boundaries of the eco-biozones widely recognised in the Western Mediterranean records and used for large scale correlations. Namely, 10 eco-biozones were identified based on the relative abundance of selected climate sensitive planktonic foraminiferal species. Sixteen codified eco-bioevents were correlated with the Alboran Sea planktonic foraminiferal data and four climatic global events (Sapropel S1, Younger Dryas, Greenland Isotope Interstadial 1, Greenland Isotope Stadial 2, Heinrich event H1-H6) were recognized. The eco-bioevents together with the 14C AMS calibrations concurred to define an accurate age model, spanning between 2 and 83 kyr cal. BP. The reliability of the age model was confirmed by comparing the colour reflectance (550 nm%) data of the studied record with the astronomically tuned one of the Ionian sea (ODP-Site 964). A mean sedimentation rate of about 7 cm/kyr was evaluated including three turbidite event beds that were chronologically constrained within the relative low stand and lowering sea level phases of the MIS 4 and MIS 3. The deep sea sedimentary record includes a distinct tephra occurring at the base of the core which dates 79 ka. The paleomagnetic data provide a well-defined record of the characteristic remanent magnetization that may be used to reconstruct the geomagnetic paleosecular variation for the Mediterranean back to 83 kyr cal. BP

Rapporto tecnino C/O Sonos2007: 5 - 30 Giugno 2007

Nel giugno 2007 si è svolta la Campagna Oceanografica "Sonos2007" a bordo della N/O Thetis. La campagna ha visto la collaborazione di due sezioni dell'IAMC (Istituto per l'Ambiente Marino Costiero - CNR), quella di Oristano e quella di Napoli nell'ambito del progetto Sigla (Sistema Integrato per monitoraggio e Gestione di Laguna e Ambiente) per la caratterizzazione litologica dei fondali nell'area di Oristano, nella Penisola del Sinis e dell'Isola di Mal di Ventre in una profondità compresa tra i 10 e i 60 metri. Come strumentazione acustica per acquisizione morfobatimetrica è stato utilizzato il Multibeam Seabat 8111, installato a chiglia della nave; mentre sono state effettuate campionature dirette con benna Van Veen per la caratterizzazione del fondale

Geohazard features of the Tyrrhenian Calabria

This paper accompanies the Maps of Geohazard features of the Cilento and the Calabro-Tyrrhenian continental margin in the southern Tyrrhenian Sea (Italy). The main geohazard-related features were derived from extensive seafloor mapping through the collection of high-resolution multibeam data acquired during several oceanographic cruises. They encompass many fluids seepage features, fault scarps, landslides scars, gullies, channels, and canyons. Hazards related to coastal landslides and shelf-indenting canyons are very high in these sectors (especially in southern Calabria) due to active seismicity coupled with rapid uplift, high sedimentation rates and narrow or totally absent continental shelf, thus promoting a direct connection between steep slopes and coastal areas. In this setting, mass-wasting features can directly impact coastal or submarine infrastructures or indirectly create local tsunami waves, as observed in historical times. Moreover, this physiographic setting of the margin facilitates the transfer of marine litter toward deep-sea areas

Rapporto tecnico C/O Sand-Waves 2002: 4 - 5 Settembre 2002

Nell’ambito del progetto di collaborazione tra l’Università degli Studi di Catania – Dipartimento di Ingegneria Civile ed Ambientale e l’Istituto per l’Ambiente Marino Costiero (IAMC) – sede Geomare del Consiglio Nazionale delle Ricerche (CNR), nei mesi di Settembre 2001 e Settembre 2002 sono state progettate e realizzate campagne oceanografiche per lo studio e il monitoraggio della “morfodinamica di macroforme di fondo” di un settore prospiciente lo Stretto di Messina. Nel presente lavoro vengono descritte le procedure di acquisizione e di elaborazione dei dati e vengono illustrati i risultati ottenuti

Rapporto tecnico C/O Carg06_03: 07 - 14 Novembre 2006

Nell'ambito del Progetto C.A.R.G. Nazionale inserito nell'accordo Servizio Geologico Nazionale - Regione Campania, si è instaurata una convenzione fra la Regione e l'Istituto per l'Ambiente Marino Costiero per la costruzione di Cartografia Geologica Marina. Tale progetto comprende, oltre all'acquisizione di dati batimetrici, anche quella di dati morofologici per mezzo di Side Scan Sonar, per garantire una giusta interpretazione geologica dei fondali. Nel periodo che va dal 7 al 14 novembre 2006 è stata organizzata la Campagna Oceanografica Carg06_03, svoltasi a bordo della N/O Thetis, per l'acquisizione di dati morfologici e campionature di fondo con benna Van Veen intorno all'isola di Ischia (Foglio 464)

New insights on the evolution of the Linosa volcano (Sicily Channel) from the study of its submarine portions

Linosa Island represents the emergent tip of a mostly submarine, much wider volcanic edifice, with at least 96% of its areal extent lying below sea level. Marine geological surveys carried out in 2016 and 2017 allowed to reconstruct the submarine portions of Linosa and to characterize the main volcanic features, providing new, unexpected insights on the evolution of this little-explored volcanic complex. In particular, the submarine setting of the NW offshore is represented by a ~10-km long volcanic belt punctuated by a number of small eruptive cones, appearing more recent with respect to the assumed Mid/Late-Quaternary age of volcanism on the island. This evidence suggests that the growth of the volcanic edifice has likely been more complex than that claimed on the base of subaerial volcanism only, and supports a north-westward migration of the activity over time. The submarine southern flank of the volcanic edifice is also characterized by eccentric eruptive cones, but mostly without evidences of recent activity. The main processes responsible for the growth and evolution of Linosa volcano and their possible relative chronology are discussed in the framework of what previously known on the base of the limited subaerial portions, with implications on the potential hazard of the volcanic edifice (considered as not-active in recent times). Similarity with the Pantelleria volcano, located in the NW Sicily Channel, are also evidenced, especially for what regards the distribution and morphometric characteristics of eruptive cones occurring in the submarine portions of both islands

VSS robust control techniques for AC motor drives

Robust control of AC asynchronous motor drives in the presence of strong parameter uncertainties is considered. Due to the different bandwidths associated with the controlled variables, a cascade structure is used. A multivariable sliding mode closed-loop controller with a hysteresis region is used to transform the voltage source inverter into a current source (CS) one. On the assumption of a CS inverter, the field-orientation principle is adopted for the design of a simplified torque and flux controller. A modified binary controller, ensuring robustness to mechanical parameter variations, is used in the outer velocity loop of the cascade control structure. Modifications to the basic binary controller are introduced to improve tracking capabilities. Performances of the proposed structure are verified by simulating a robotic application. Tracking of a velocity trajectory for a single-link robotic arm is considered. Simulation results show the feasibility and good performance of the robust control structure