GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Type of Medium: Book
    Pages: XX, S. 515-879 , Ill., graph. Darst.
    Series Statement: Annals of geophysics 49.2006,2/3
    Language: English
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2021-03-02
    Description: The deep seismicity and lateral distribution of seismic velocity in the CentralWesternMediterranean, point to the existence under the Alboran and Tyrrhenian Seas of two lithospheric slabs reaching the mantle transition zone. Gibraltar and Calabrian narrow arcs correspond to the slabs. Similarities in the tectonic and mantle structure of the two areas have been explained by a common subduction and roll-back mechanism, in which the two arcs are symmetrical end members. We present a new 3-D tomographic model at mantle scale for the Calabrian Arc and compare it with a recently published model for the Gibraltar Arc by Monna et al. (2013a). The two models, calculated with inversion of teleseismic phase arrivals, have a scale and parametrization that allow for a direct comparison. The inclusion in both inversions of ocean bottom seismometer broadband data improves the resolution of the areas underlying the seafloor networks. This additional information is used to resolve the deep structure and constrain the reconstruction of the Central Western Mediterranean geodynamic evolution. The Gibraltar tomography model suggests that the slab is separated from the Atlantic oceanic domain by a portion of African continental margin, whereas the Calabrian model displays a continuous oceanic slab that is connected, via a narrow passage (~350 km), to the Ionian basin oceanic domain. Starting from the comparison of the two models we propose the following interpretation: within the Mediterranean geodynamic regime (dominated by slab rollback) the geometry of the African continental margin, located on the lower plate, represents a critical control on the evolution of subduction. As buoyant continental lithosphere entered the subduction zones, slab pull caused tears in the subducted lithosphere. This tectonic response,which occurred in the final stages of arc evolution and was strongly controlled by the paleogeography of the subducted plates, explains the observed differences between the Gibraltar and Calabrian Arcs.
    Description: Published
    Description: 135-152
    Description: 7T. Struttura della Terra e geodinamica
    Description: JCR Journal
    Keywords: Teleseismic tomography ; Upper mantle ; Gibraltar Arc ; Calabrian Arc ; Subduction zone ; 04.06. Seismology ; 04.01. Earth Interior ; 04.07. Tectonophysics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2021-06-25
    Description: Understanding micro-seismicity is a critical question for earthquake hazard assessment. Since the devastating earthquakes of Izmit and Duzce in 1999, the seismicity along the submerged section of North Anatolian Fault within the Sea of Marmara (comprising the “Istanbul seismic gap”) has been extensively studied in order to infer its mechanical behaviour (creeping vs locked). So far, the seismicity has been interpreted only in terms of being tectonic-driven, although the Main Marmara Fault (MMF) is known to strike across multiple hydrocarbon gas sources. Here, we show that a large number of the aftershocks that followed the M 5.1 earthquake of July, 25th 2011 in the western Sea of Marmara, occurred within a zone of gas overpressuring in the 1.5–5 km depth range, from where pressurized gas is expected to migrate along the MMF, up to the surface sediment layers. Hence, gas-related processes should also be considered for a complete interpretation of the micro-seismicity (~M 〈 3) within the Istanbul offshore domain.
    Description: Published
    Description: id 6819
    Description: 3A. Geofisica marina e osservazioni multiparametriche a fondo mare
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2021-01-04
    Description: T-waves are acoustic waves generated by earthquakes at the land-water interface. They can propagate efficiently for thousands of kilometers within the ocean’s low-velocity waveguide - the SOund Fixing And Ranging (SOFAR) channel. In the present work we studied T-waves that propagate in the Ionian basin and are generated by regional earthquakes (epicentral distance 〈 1000 Km) located in the Hellenic Arc (Greece). The Ionian Sea is a small basin that has strong bathymetric variations and is limited at its western edge by a steep continental slope - the Malta Escarpment. T-waves from Greece were recorded by a broad band seismometer on-board of one of seafloor observing unit of the Western Ionian Regional Facility of EMSO- European Research Infrastructure (www.emso.eu) deployed in the western Ionian Sea (Italy) at about 2100 m water depth. By studying the particle motion and energy flux (TPEF) of the T-waves recorded at the observatory, we find that the western Ionian Sea bathymetry is an efficient reflector for T-phases within the SOFAR channel. To investigate if factors other than T-wave path effects drive TPEF levels, we also study the source part of the T-wave generation process.
    Description: Published
    Description: 481–493
    Description: 3A. Geofisica marina e osservazioni multiparametriche a fondo mare
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2021-01-27
    Description: The SEISMOFAULTS project (www.seismofaults.it) was set up in 2016 with the general plan of exploring the seismicity of marine areas using deep seafloor observatories. The activity of the first two years (Seismofaults 2017 and 2018) consisted of the installation of a geophysical-geochemical temporary monitoring network over the Ionian Sea floor. Eleven ocean-bottom seismometers with hydrophones (OBS/H) and two seafloor geochemical-geophysical multiparametric observatories were deployed to: (1) identify seismically active faults; (2) identify potential geochemical precursors of earthquakes; and (3) understand possible cause–effect relationships between earthquakes and submarine slides. Furthermore, five gravity cores were collected from the Ionian Sea bottom and ~4082 km of geophysical acquisition, including multibeam and single channel seismic reflection data, were acquired for a total of 4970 km2 high-resolution multibeam bathymetry. Using Niskin bottles, four water column samples were collected: two corresponding at the location of the two multiparametric observatories (i.e., along presumably-active fault zones), one corresponding at a recently discovered mud volcano, and one located above a presumably-active fault zone away from the other three sites. Preliminary results show: (1) a significant improvement in the quality and quantity of seismological records; (2) endogenous venting from presumably active faults; (3) active geofluid venting from a recently-discovered mud volcano; and (4) the correct use of most submarine devices. Preliminary results from the SEISMOFAULTS project show and confirm the potential of multidisciplinary marine studies, particularly in geologically active areas like southern Italy and the Mediterranean Sea.
    Description: Published
    Description: SE326
    Description: 3A. Geofisica marina e osservazioni multiparametriche a fondo mare
    Description: JCR Journal
    Keywords: Earthquake; Ionian Sea; OBS.
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2020-04-06
    Description: The Ionian Sea area is a known site of seismic hazard. Several historical highmagnitude earthquakes occurred in the area (e.g., 1193, M=6.6; 1693, M=7.4; 1908, M=7.2) [Boschi et al., 1997], whose tectonic sources and generation mechanism are still debated. Due to the lack of a seafloor seismic network the detection and location of marine earthquakes are often elusive. The SEISMOFAULTS experiment [http://www.seismofaults.it/] was performed between 2017 May and 2018 May to increase knowledge on the seismicity in the western Ionian Sea. Seven broadband Ocean Bottom Seismometers and Hydrophones
    Description: Published
    Description: Rome
    Description: 3A. Geofisica marina e osservazioni multiparametriche a fondo mare
    Keywords: Marine Geophysics ; Ocean Bottom Seismometer ; Active Tectonics ; 04.02. Exploration geophysics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: Conference paper
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2017-04-04
    Description: Science Festivals are events world wide organized, and they have became more and more one of the most effective playground where science meet people. Genova Science Festival, held since 2003, is the Italian most interesting event of that type. The Istituto Nazionale di Geofisica e Vulcanologia (INGV), one of the largest European scientific institution deal- ing with Earth Sciences research and real-time surveillance, early warning, and forecast activities in geophysics and volcanology, participates every year developing a specific educational path, concerning some of its research areas. For the 2010 Genova Science Festival, the INGV has produced an educational exhibition called “Mediterraneo Dinamico” (Dynamic Mediterranean). This is a journey in the geodynamical history of the Mediterranean region from 200 million years ago till present. This long process took place also through some instantaneous dramatic events as eruptions, tsunami, earthquakes, whose studies have revealed their strong impact on cultural Mediterranean evolution as well as on environmental aspects as climate. The exhibition path aim is to illustrate and explain to general public, and especially to teachers and students, the results from researches conducted by INGV also in collaboration with other Italian and International partners, as well as from the real time Mediterranean sea water monitoring. The chosen exhibition instruments are wide colourful illustrated posters, greatly illustrated, together with smart interactive exhibits. In particular the path starts with a “Time Machine”, that allows visitors to retrace the main steps of the Mediterranean geological evolution, supported by posters. The following section concerning the “Mediterranean catastrophic event” welcome visitors with a glass pyramid projecting a virtual eruption almost as an “ologramma”, and side panels with two short videos explaining two great explosive eruptions and a tsunami event. The section on Mediterranean Tsunami are equipped with an interactive large map of the location of Mediteranean where occurred tsunami events, illustrated posters and also a microscope with a camera where visitors can analyse a core with a tsunami deposits. Also an interactive model of a GEOSTAR - Geophisical and Oceanographic Station of Abyssal Research provide visitors an entertaining approach on how a submarine observatory works with all his sensors, while a computer station permits visitors to read real time measures of some marine environmental indicators. The exhibition journey trough the Mediterranean geo-history and Earth Science and Geophysical research shows how the continuous knowledge and monitoring of to this Region dynamics are fundamental to design a future bearable development for the 30 million people living along the Mediterranean shores.
    Description: Published
    Description: Vienna- Austria
    Description: 5.9. Formazione e informazione
    Description: open
    Keywords: science exibition ; 05. General::05.03. Educational, History of Science, Public Issues::05.03.99. General or miscellaneous
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: Poster session
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2020-04-27
    Description: The Marsili Seamount is the largest European underwater volcano. It is Plio-Pleistocenic in age, rising up to more than 3000m from the seafloor in the SE Tyrrhenian basin (Central Mediterranean), a back arc basin which began progressively opening 10 Ma ago (Kastens et al., 1988). The seamount lies in a key area for understanding the evolution of the Tyrrhenian region, characterized by high values of heat flow (Della Vedova et al., 2001) and low values of Moho isobaths (Locardi and Nicolich, 1988). In spite of the large dimensions of the Marsili seamount, we still have limited knowledge of its present activity. Ocean exploration is dependent on available technology and infrastructure, which started to develop strongly only after the 1980s. In fact, from its discovery in the 1920s, very little was known of the Marsili Seamount until the late 1990s when new techniques such as multibeam acoustic bathymetry were developed allowed to reveal at least the morphology. Some dedicated expeditions then obtained the first morpho-bathimetric map of the entire Tyrrhenian seafloor, based on multibeam swath-mapping together with seismic, gravimetric and magnetometric data (e.g. Marani and Gamberi, 2004). Although these data have greatly contributed to our understanding, the necessarily short measurement time limits the extent to which they reflect short- to medium-term geophysical processes in the Tyrrhenian basin. New technologies, such as multiparameter seafloor observatories, provide long-term continuous time-series in deep ocean waters, which are the basis for an original approach in ocean exploration. The observation of phenomena variability over time is key to understanding many Earth processes, among which we recall hydrothermal activity, active tectonics, and ecosystem life cycles. The development in Europe of multidisciplinary seafloor observatories has been pioneered under the EC Framework Programmes, specifically in the GEOSTAR projects (Beranzoli et al., 1988, 2000). From 2003 to 2005, long-term geophysical and oceanographic monitoring was conducted within the EC ORION-GEOSTAR3 project with two multiparameter observatories deployed on the seafloor 3320m below sea level (b.s.l.) in the vicinity of the Marsili Seamount. The two observatories were equipped with a set of sensors providing long-term continuous time-series of various physical measurements. The acquired time series are the longest continuous data record of the Marsili Basin available so far. This chaper intends to provide the main information on this experiment and present some results of the processing of the corresponding time-series, adding new valuable information on the still poorly explored activity of the volcano seamount. This chapter is organized as follows: The next section will provide the geological setting to understanding the importance of the Marsili Seamount and its basin; the ORION-GEOSTAR3 experiment is described in Section 24.3; some results from this unprecedented seismic, magnetic and gravimetric data analyses are shown in Section 24.4; and finally, in the last section we present our discussion with the main conclusions.
    Description: Published
    Description: 623-641
    Description: 3A. Geofisica marina e osservazioni multiparametriche a fondo mare
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: book chapter
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2021-08-30
    Description: Seismological data recorded in the Ionian Sea by a network of seven Ocean Bottom Seismometers (OBSs) during the 2017–2018 SEISMOFAULTS experiment provides a close-up view of seismogenic structures that are potential sources of medium-high magnitude earthquakes. The high-quality signal-to-noise ratio waveforms are observed for earthquakes at different scales: teleseismic, regional, and local earthquakes as well as single station earthquakes and small crack events. In this work, we focus on two different types of recording: 1) local earthquakes and 2) Short Duration Events (SDE) associated to micro-fracturing processes. During the SEISMOFAULTS experiment, 133 local earthquakes were recorded by both OBSs and land stations (local magnitude ranging between 0.9 and 3.8), while a group of local earthquakes (76), due to their low magnitude, were recorded only by the OBS network. We relocated 133 earthquakes by integrating onshore and offshore travel times and obtaining a significant improvement in accuracy, particularly for the offshore events. Moreover, the higher signal-to-noise ratio of the OBS network revealed a significant seismicity not detected onshore, which shed new light on the location and kinematics of seismogenic structures in the Calabrian Arc accretionary prism and associated to the subduction of the Ionian lithosphere beneath the Apennines. Other signals recorded only by the OBS network include a high number of Short Duration Events (SDE). The different waveforms of SDEs at two groups of OBSs and the close correlation between the occurrence of events recorded at single stations and SDEs suggest an endogenous fluid venting from mud volcanoes and active fault traces. Results from the analysis of seismological data collected during the SEISMOFAULTS experiment confirm the necessity and potential of marine studies with OBSs, particularly in those geologically active areas of the Mediterranean Sea prone to high seismic risk.
    Description: Published
    Description: 661311
    Description: 3A. Geofisica marina e osservazioni multiparametriche a fondo mare
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2023-01-30
    Description: In spite of numerous active and passive seismological investigations, the existence of continuous or interrupted continental subduction below the Western Alps is still open to debate. Many of the observations focus on the Moho or the deeper part of the mantle, while reliable information on the Lithosphere-Asthenosphere Boundary (LAB) below the Alpine region is scarce. Exploiting the data from the dense, broadband AlpArray Seismic Network we present a set of Receiver Function (RF) measurements on the Moho and LAB of a region encompassing the Western Alps, which includes the Ivrea Geophysical Body (IGB), a fragment of mantle placed at a few kilometers depth at the collision margin between Eurasia and Adria plates. We derive seismic velocity profiles of the crust-uppermost mantle below each station down to about 250 km, through the joint inversion of P and S RF. We constrain the lateral variations of the Moho and LAB topographies across the colliding plates, and quantify the errors related to our measurements. Our results allow us to considerably expand the published data of the Moho depth and to add a unique set of new measurements of the LAB. Our observations show that Eurasia and Adria lithospheres have a comparable thickness (on average 90–100 km), and are colliding below the IGB, and that Eurasia is not presently continuously subducting below Adria. These observations suggest that there is a gap between the superficial (continental) European lithosphere and the deep (oceanic) lithosphere, confirming the discontinuous structure imaged by some seismic tomography models.
    Description: Published
    Description: e2022JB025141
    Description: 1T. Struttura della Terra
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...