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::04.04.02. Geochronology  (2)
  • 04. Solid Earth::04.06. Seismology::04.06.07. Tomography and anisotropy
  • 04.02. Exploration geophysics
  • Allgemeine Geographie
  • Blackwell  (2)
  • elsevier  (2)
Collection
Years
  • 1
    Publication Date: 2017-04-04
    Description: The island of Pantelleria (Sicily Strait), the type locality for pantellerite, has been the locus of major calderaforming eruptions that culminated, ca. 50 ka ago, in the formation of the Cinque Denti caldera produced by the Green Tuff eruption. The post-caldera silicic activity since that time has been mostly confined inside the caldera and consists of smaller-energy eruptions represented by more than twenty coalescing pantelleritic centers structurally controlled by resurgence and trapdoor faulting of the caldera floor. A high-resolution 40Ar/39Ar study was conducted on key units spanning the recent (post-20 ka) intracaldera activity to better characterize the present-day status (and forecast the short-term behavior of) the system based on the temporal evolution of the latest eruptions. The new 40Ar/39Ar data capture a long-term (N15 ka) decline in eruption frequency with a shift in eruptive pace from 3.5 ka−1 to 0.8 ka−1 associated with a prominent paleosol horizon marking the only recognizable volcanic stasis around 12–14 ka. This shift in extraction frequency occurswithoutmajor changes in eruptive style, and is paralleled by a subtle trend of decreasingmelt differentiation index. We speculate that this decline probably occurred (i) without short-term variations in melt production/differentiation rate in a steadystate compositionally-zoned silicic reservoir progressively tapped deeper through the sequence, and (ii) that it was possibly modulated by outboard eustatic forcing due to the 140 m sea level rise over the past 21 ka. The intracaldera system is experiencing a protracted stasis since 7 ka. Coupled with recent geodetic evidence of deflation and subsidence of the caldera floor, the system appears today to be on a wane with no temporal evidence for a short-term silicic eruption.
    Description: Published
    Description: 280-290
    Description: 3.5. Geologia e storia dei vulcani ed evoluzione dei magmi
    Description: JCR Journal
    Description: reserved
    Keywords: pantelleria 40Ar/39Ar xenocrysts excess 40Ar anorthoclase ; 04. Solid Earth::04.04. Geology::04.04.02. Geochronology
    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: To study the applicability of the passive seismic interferometry technique to near-surface geological studies, seismic noise recordings from a small scale 2-D array of seismic stations were performed in the test site of Nauen (Germany). Rayleigh wave Green's functions were estimated for different frequencies. A tomographic inversion of the traveltimes estimated for each frequency from the Green's functions is then performed, allowing the laterally varying 3-D surface wave velocity structure below the array to be retrieved at engineering–geotechnical scales. Furthermore, a 2-D S-wave velocity cross-section is obtained by combining 1-D velocity structures derived from the inversion of the dispersion curves extracted at several points along a profile where other geophysical analyses were performed. It is shown that the cross-section from passive seismic interferometry provides a clear image of the local structural heterogeneities that are in excellent agreement with georadar and geoelectrical results. Such findings indicate that the interferometry analysis of seismic noise is potentially of great interest for deriving the shallow 3-D velocity structure in urban areas.
    Description: Published
    Description: 164-174
    Description: 4.1. Metodologie sismologiche per l'ingegneria sismica
    Description: JCR Journal
    Description: open
    Keywords: Interferometry ; seismic tomography ; 04. Solid Earth::04.06. Seismology::04.06.07. Tomography and anisotropy
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2017-04-04
    Description: Buried sedimentary aggradational sections deposited between 800 ka and 600 ka in the Tiber River coastal alluvial plain have been studied using borecores from around Rome. 40Ar/39Ar ages on sanidine and/or leucite from intercalated tephra layers and paleomagnetic investigation of clay sections provide geochronologic constraints on the timing of aggradation of two alluvial sections, demonstrating that they were deposited in response to glacio–eustatic sea level rise caused by Glacial Terminations IX and VII. 40Ar/39Ar age data indicate ages of 802±8 ka (1σ full errors) and 649±3 ka (1σ full errors) for Glacial Terminations IX and VII, respectively, providing a rare test, beyond the range of U-series dating for corals and speleothems (∼500 ka), of the astronomically calibrated timescale developed for oxygen isotope records from deep sea cores.
    Description: Published
    Description: 61-80
    Description: 2.2. Laboratorio di paleomagnetismo
    Description: JCR Journal
    Description: reserved
    Keywords: glacial termination ; sea level ; 40Ar/39Ar ; Tiber River delta ; paleomagnetism ; 04. Solid Earth::04.04. Geology::04.04.02. Geochronology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2017-04-04
    Description: Stromboli volcano (Italy) is characterized by a permanent mild explosive activity disrupted by major and paroxysmal eruptions. These strong eruptions could be triggered by phreatomagmatic processes. With the aim of obtaining a better understanding of ground water flow in the vicinity of the active vents, we carried out a set of geophysical measurements along two profiles crossing the Fossa area (through the Pizzo, the Large and the Small Fossa craters). These measurements include electrical resistivity, induced polarization, self-potential, temperature and CO2 ground concentration. These methods are used in order to delineate the crater boundaries, which act as preferential fluid flow pathways for the upflow of hydrothermal fluids. The absence of fumarolic activity in the Fossa area and the ground temperature close to 100 °C at a depth of 30 cm indicate that the hydrothermal fluids condense close to the ground surface. Part of this condensed water forms a shallow drainage network (〈20 m) in which groundwater flows downslope toward a perched aquifer. The piezometric surface of this aquifer is located ∼20 m below the topographic low of the Small Fossa crater and is close (〈100 m) to the active vents. Electrical resistivity tomography, temperature and CO2 measurements show that this shallow aquifer separates the underlying hydrothermal body from the ground surface. Further studies are needed to ascertain the size of this aquifer and to check its possible implications for the major and paroxysmal events observed at the Stromboli volcano.
    Description: Published
    Description: 426–440
    Description: partially_open
    Keywords: fluid flow ; CO2 soil concentration ; Self-potential ; Stromboli ; volcanic activity ; 04. Solid Earth::04.02. Exploration geophysics::04.02.04. Magnetic and electrical methods ; 04. Solid Earth::04.04. Geology::04.04.11. Instruments and techniques ; 04. Solid Earth::04.06. Seismology::04.06.06. Surveys, measurements, and monitoring ; 04. Solid Earth::04.06. Seismology::04.06.07. Tomography and anisotropy
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Format: 878606 bytes
    Format: 543 bytes
    Format: application/pdf
    Format: text/html
    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...