ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • 04. Solid Earth::04.04. Geology::04.04.09. Structural geology  (9)
  • 04. Solid Earth::04.06. Seismology::04.06.06. Surveys, measurements, and monitoring
  • 04.07. Tectonophysics
  • AGU  (14)
  • Wiley  (7)
Collection
  • 1
    Publication Date: 2020-10-16
    Description: Recent satellite geodetic measurements help to clearly define the velocity field in the Aegean-Anatolian area. The velocity field can be broadly characterized by anticlockwise rotation of this region relative to Eurasia, around a pole located at Lat. 32.73, Long. 32.03, north of the Egyptian shoreline. Studies of the fault kinematics in the region also provide information on the time evolution of the stress field. In this work, we model deformation in the Aegean-Anatolian region to better understand the tectonic origin of the observed stress and velocity fields. We found that the observed deformation pattern can be well reproduced by imposing simple boundary conditions including: (1) northward displacement of the Arabian plate, (2) locking of eastward motion in northwestern Greece and (3) suction force at the Hellenic trench. The observed variation in the stress field occurred at 0.9 Ma can be partially explained by a change in the activity of the North Anatolian fault.
    Description: Published
    Description: 2087-2090
    Description: 2T. Deformazione crostale attiva
    Description: JCR Journal
    Keywords: Plate Motion ; Continental tectonics ; Dynamics of lithosphere and mantle ; Plate boundary ; 04.07. Tectonophysics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2017-04-04
    Description: Radon emissions are frequently monitored in volcanically and tectonically active areas in order to reveal changes in soil degassing, as radon acts a tracer for the more abundant CO2 degassing commonly observed in such areas. Between July 2002 and May 2003 a series of discrete measurements of radon concentrations in soil were made with high spatial resolution (∼5–100 m) in the Santa Venerina area on Mt. Etna. These measurements revealed well-defined linear anomalies that we interpret as being caused by active faults whose higher porosity than surrounding soils allows an increased CO2 flux, carrying radon from beneath. These faults were not visible at the surface and were therefore revealed at high spatial resolution by our radon survey. Our hypothesis that the positive anomalies are attributable to active faults was strengthened by the observation of concentrated damage along this geometry during the earthquakes that struck this area in late October 2003.
    Description: Published
    Description: 4
    Description: partially_open
    Keywords: Structural Geology: Role of fluids ; Structural Geology: Fractures and faults ; Structural Geology: Instruments and techniques ; Volcanology: Instruments and techniques ; 04. Solid Earth::04.04. Geology::04.04.09. Structural geology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Format: 713186 bytes
    Format: 490 bytes
    Format: application/pdf
    Format: text/html
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2017-04-04
    Description: Source and Qp parameters were estimated from the inversion of first arrival P waveform durations of about 300 microearthquakes recorded at a digital seismic network operating in southeastern Sicily. The average risetime and pulse width at each station do not show large differences, allowing us to exclude significant differential attenuation site effects. A first Qp estimate was obtained by applying the classical risetime method, under the assumption of a point-like source time function. In order to investigate the effect of directivity due to the finiteness of seismic sources, new nonlinear relationships, based on a circular crack model rupturing at a constant velocity, were numerically built. These relationships were used to formulate a nonlinear inverse method for retrieving source (radius, dip, and strike of the circular crack) and Qp parameters from the inversion of risetime and pulse width data. The application of the method produced a better fit of the observed data and a Qp value higher than that obtained by applying the risetime method. The discrepancy between the different Q estimates may be due to a trade-off among source dimension and Qp, as we inferred from a test on a subset of low-magnitude events (Ml ≤ 2.5). A good agreement with independent estimates of fault plane solutions, as inferred from P polarities and S polarizations, was found. The estimated stress drops are generally very low (0.1–10 bars). This suggests that the background seismic activity in southeastern Sicily is related to fault segments and/or weakened zones where great stress accumulations are hindered.
    Description: Published
    Description: 1-14
    Description: partially_open
    Keywords: source and Qp parameters ; risetime ; pulse width ; attenuation ; 04. Solid Earth::04.06. Seismology::04.06.01. Earthquake faults: properties and evolution ; 04. Solid Earth::04.06. Seismology::04.06.02. Earthquake interactions and probability ; 04. Solid Earth::04.06. Seismology::04.06.06. Surveys, measurements, and monitoring
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Format: 490 bytes
    Format: 654914 bytes
    Format: text/html
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2017-04-04
    Description: This study concerns the unstable scarp named Sciara del Fuoco (SDF) at Stromboli volcano, merging geostructural observations, live-cam records in the visible and IR bands, analysis of vertical aerial photographs, and seismic records. These are used to assess morpho-structural changes between 2002 and 2004. The onset of the lava effusion on 28 December, 2002 preceded a gravitational collapse by two days, affecting a wide area of the SDF above and below sea level. We surmise that the collapse enhanced latent instability of the scarp. The 2002–2003 lava flows had a remarkable stabilizing effect on wide portions (〉50%) of the SDF, whilst erosive phenomena continued in the zone not covered by lava. This caused unrelenting regression of the upper landslide scarp toward the summit craters in the form of rockfalls and debris flows. If the crater conduit were involved in the sliding, then a change in eruptive behavior cannot be excluded.
    Description: Published
    Description: L09304
    Description: reserved
    Keywords: NONE ; 04. Solid Earth::04.02. Exploration geophysics::04.02.99. General or miscellaneous ; 04. Solid Earth::04.04. Geology::04.04.09. Structural geology ; 04. Solid Earth::04.07. Tectonophysics::04.07.07. Tectonics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Format: 3767834 bytes
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2017-04-04
    Description: Soil radon emissions have been proved as a useful tool for predicting earthquakes and volcanic eruptions and furthermore aided in determining the location of active faults. Continuous radon monitoring was carried out near Southeast Crater of Mt. Etna in September–November 1998, during a period of frequent eruptive episodes at that crater. Radon anomalies were detected when eruptive episodes and the accompanying volcanic tremor became increasingly intense: no anomalies in radon activity were observed during the first five, and weaker, eruptive episodes, whereas significant spikes in radon activity preceded the latter five episodes by ≥46 hours. This probably reflects increased gas leakage through fractures intersecting the shallow plumbing system, as gas pressure in the Southeast Crater conduit became higher with time. Radon monitoring thus might serve to better understand eruptive mechanisms and possible precursors, making further studies in this field a promising perspective.
    Description: Published
    Description: 1-4
    Description: partially_open
    Keywords: Seismology: Volcano seismology ; Structural Geology: Role of fluids ; Volcanology: Volcano monitoring ; Volcanology: Instruments and techniques ; 04. Solid Earth::04.04. Geology::04.04.09. Structural geology ; 04. Solid Earth::04.06. Seismology::04.06.08. Volcano seismology ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring ; 04. Solid Earth::04.08. Volcanology::04.08.07. Instruments and techniques
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Format: 490 bytes
    Format: 152534 bytes
    Format: text/html
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2017-04-04
    Description: Dikes provide crucial information on how magma propagates within volcanoes. Somma-Vesuvio (Italy) consists of the active Vesuvio cone, partly bordered by the older Mt. Somma edifice. Historical chronicles on the fissure eruptions in 1694–1944 are matched with an analytical solution to define the propagation path of the related dikes and to study any control of the Mt. Somma relief. The fissures always consisted of the downslope migration of vents from an open summit conduit, indicating lateral propagation as the predominant mechanism for shallow dike emplacement. No fissure emplaced beyond Mt. Somma, suggesting that its buttressing hinders the propagation of the radial dikes. An analytical solution is defined to describe the mechanism of formation of the laterally propagating dikes and to evaluate the effect of topography. The application to Somma-Vesuvio suggests that, under ordinary excess magmatic pressures, the dikes should not propagate laterally at depths 〉240–480 m below the surface, as the increased lithostatic pressure requires magmatic pressures higher than average. This implies that, when the conduit is open, the lateral emplacement of dikes is expectable on the S, Wand E slopes. The lack of fissures N of Mt. Somma is explained by its buttressing, which hinders dike propagation. Citation: Acocella, V., M. Porreca, M. Neri, E. Massimi, and M. Mattei (2006), Propagation of dikes at Vesuvio (Italy) and the effect of Mt. Somma, Geophys. Res. Lett., 33, L08301, doi:10.1029/2005GL025590.
    Description: Published
    Description: L08301
    Description: reserved
    Keywords: NONE ; 01. Atmosphere::01.01. Atmosphere::01.01.03. Pollution ; 04. Solid Earth::04.04. Geology::04.04.09. Structural geology ; 04. Solid Earth::04.07. Tectonophysics::04.07.07. Tectonics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Format: 5097648 bytes
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2017-04-04
    Description: Understanding how shallow magma is emplaced within volcanoes is crucial for hazard assessment. The 2002–2003 Stromboli eruption provides the opportunity to investigate shallow magma emplacement resulting from orthogonal feeder dikes and its possible effects. Stromboli erupted in 2002–2003, when effusive activity replaced Strombolian activity. On December 28, a NE-SW fissure propagated from the lava-filled northernmost summit crater. On December 29, a NW-SE fissure propagated north of the craters, feeding NW-SE aligned vents. On December 30, this area collapsed, reaching the sea and generating a tsunami. In mid February 2003, the NW-SE fissure became inactive, while the NE-SW effusive fissure continued until July. A model for shallow magma emplacement is proposed. The lateral propagation of a NE-SW dike from the northernmost crater was triggered. Below, a NW-SE dike, propagating from the magma-filled NE tip of the NE-SW elongated conduit, fed the NW-SE aligned vents. In February, the conduit periphery became solidified, freezing the NW-SE dike, and the transport of magma was limited to the central part, focusing its rise below the craters. This fed the NE-SW fissure until the supply decreased further (July), returning to the ordinary level sustaining Strombolian activity. Orthogonal dike emplacement followed the trajectories of the maximum (gravitational) stress s1, partly controlled by the irregular topography of the uppermost edifice. The emplacement of orthogonal dikes in a limited area is feasible at non-perfectly conical active volcanoes, where the maximum gravitational stress may show variations from a purely radial path.
    Description: Published
    Description: L17310
    Description: reserved
    Keywords: NONE ; 04. Solid Earth::04.04. Geology::04.04.09. Structural geology ; 04. Solid Earth::04.07. Tectonophysics::04.07.05. Stress ; 04. Solid Earth::04.07. Tectonophysics::04.07.07. Tectonics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Format: 3375462 bytes
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2017-04-04
    Description: We detect seismic wave velocity changes at Mt. Vesuvius, using doublets and the Coda Wave Interferometry method. The high sensitivity of multiply scattered coda waves to temporal changes in the medium allows us to detect velocity variation smaller than 0.4%. We use 17 doublets, some of them grouped in families of multiplets, spanning January 1996 to December 1999. Data show a systematic increase in velocity from 1996 to end- September 1999, followed by a rapid drop in velocity. This drop immediately precedes a sustained swarm of VT-type earthquakes, including the 9th October 1999 M = 3.6 event, the largest in the region since at least 1972. We propose a long term fluid pressurization followed by influx as a possible causative mechanism.
    Description: Published
    Description: L06306
    Description: reserved
    Keywords: NONE ; 04. Solid Earth::04.06. Seismology::04.06.06. Surveys, measurements, and monitoring
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Format: 1508425 bytes
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2017-04-04
    Description: The Institute for Geophysics at Hamburg University and the Research Center for Marine Geoscience (GEOMAR) of Kiel University have developed new, wideband ocean bottom seismic stations for long-term, deep sea deplyments of up to 1 year.
    Description: Published
    Description: 309-315
    Description: 1.4. TTC - Sorveglianza sismologica delle aree vulcaniche attive
    Description: open
    Keywords: Ocean Bottom Seismometer ; Tyrrhenian Sea ; 04. Solid Earth::04.06. Seismology::04.06.06. Surveys, measurements, and monitoring
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2017-04-04
    Description: During local and regional earthquakes, an evident amplification of horizontal ground motion is observed at two seismological stations near the Tremestieri fault, on the southeastern flank of Mt. Etna volcano. Rotated-component spectral ratios show a narrow spectral peak around 4-Hz along a N40°E direction. A conventional polarization analysis using the eigenvectors of the covariance matrix confirms the very stable directional effect enhancing the approximately NE-SW elongation of the horizontal ground motion in the fault zone. The effect is evident during the entire seismogram and independent of source backazimuth as well as distance and depth of earthquakes. The same polarization is observed in ambient noise as well. This consistency allowed us to use microtremors for checking ground motion polarization along and across the Tremestieri fault zone with a high spatial resolution. The result is a stable polarization of horizontal motion in the entire area, interesting a broad frequency band. To check whether this ground motion property is recurrent and understand a possible relationship with fault strike, faulting style, or orientation of fractures, ambient noise was recorded on other mapped faults of the Mt. Etna area, the Moscarello, Acicatena and Pernicana faults. The latter, in particular, is characterized by different strike and faulting style. A systematic tendency of ambient noise to be polarized is found in all of the faults. A picture emerges where normal faults of the eastern flank show a E-W to NE-SW polarization that changes on the Pernicana fault, which develops approximately E-W and is characterized by a prevailing NW-SE to NS polarization. Directions of polarization were never parallel to the fault strike. Moreover, polarization persists too far away from the fault trace, excluding an effect limited to a narrow low velocity zone hosted between harder wall rocks. Both these observations rule out an interpretation in terms of fault-trapped waves. The cause of observed polarizations will be the subject of future studies. However, the consistency with recent results of velocity anisotropy in a part of the investigated area suggests a possible role of attenuation anisotropy on horizontal amplitude variations versus azimuth.
    Description: Published
    Description: B10306
    Description: 4.1. Metodologie sismologiche per l'ingegneria sismica
    Description: JCR Journal
    Description: open
    Keywords: polarization ; fault zones ; Etna volcano ; microtremors ; 04. Solid Earth::04.06. Seismology::04.06.04. Ground motion ; 04. Solid Earth::04.06. Seismology::04.06.06. Surveys, measurements, and monitoring ; 04. Solid Earth::04.06. Seismology::04.06.08. Volcano seismology ; 04. Solid Earth::04.06. Seismology::04.06.09. Waves and wave analysis ; 04. Solid Earth::04.06. Seismology::04.06.11. Seismic risk
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...