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Allegretti

et al. 2009

Bull Earthquake Eng

Self Cite

Horizontal-to-vertical spectral ratios (HVSR) of ambient vibrations measured in the ancient town of Ston (Croatia) on 99 locations, are shown to be well matched to the theoretical ones computed for body-waves as well as for the surface waves. This match is poorer for sites on the slopes of nearby hills. The ratios of measured peak horizontal ground acceleration during the damaging earthquake in 1996 (M L = 6.0) and the ones obtained using empirical attenuation laws is approximately equal to the mapped value of the dynamic amplification factor determined on the basis of observed HVSR in the vicinity of the accelerometric station. The HVSR of the accelerogram is very similar to the HVSR of the ambient noise. The damage to the building stock in the old town centre caused by the earthquake series of 1996 is closely related to the estimated soil amplification and its fundamental frequency. More measurements in buildings are needed to arrive at confident conclusions about possible soil-structure resonance.

Section: Macroseismic Observationsmentioning

confidence: 99%

HVSR of ambient noise in Ston (Croatia): comparison with theoretical spectra and with the damage distribution after the 1996 Ston-Slano earthquake

Allegretti

et al. 2009

Bull Earthquake Eng

Self Cite

“…It is characterized by moderate-to-strong earthquakes that are the result of the subduction of the Adriatic microplate under the External Dinarides [25]. The most recent significant earthquake with a magnitude of 6.0 occurred near Ston in 1996 with a hypocenter at 15 km [14,[48][49][50]. The mainshock was felt around 400 km away, with numerous aftershocks within 50 km from the main epicenter, which lasted for a year [14].…”

Section: Structural Geology and Seismicitymentioning

confidence: 99%

Late Quaternary Evolution of a Submerged Karst Basin Influenced by Active Tectonics (Koločep Bay, Croatia)

Šolaja¹,

Miko

Brunović

et al. 2022

JMSE

Koločep bay is a 30 km elongated karst basin located between the Elafiti Islands and the mainland with a NW–SE general direction. The bay lies within the seismically active southern Dalmatia zone. Irregular grid sub-bottom profiles and two legacy reflection seismic profiles have been used to determine the overall morphology of the bay and to establish the seismic stratigraphy of its sedimentary infill. Three major seismic–stratigraphic units have been identified in the upper ~50 m of the ~120-meter-thick sedimentary sequence that lies above the karstified limestone bedrock. The karst polje basin was flooded due to sea-level rise before 12.1 kyr BP. The morphology of the bay implies complex influences of Late Glacial meltwater discharges, aeolian sand deposition, the existence of paleo–ponor/karst spring zones and buried Pleistocene river channels. The Pleistocene seismotectonic units are deformed in the NW and SE parts of the basin. The central part of the basin has no signatures of intensive tectonic activity during the Holocene. A major erosion event was identified that led to the formation of a basin within the older sedimentary infill. In the southern part of the basin, we have evidence of Holocene tectonic activity with the formation of erosional scarps on the seafloor of the bay.

“…1 DT: Centroid time minus hypocentre time; C: Centroid location; E: Microseismic epicentre; BDC: Best Double-Couple; FMS: The first P-wave polarity Focal Mechanism Solution. 2 USGS [32], GCMT [33], ISC [34], ISC-GEM [35], RCMT [36].…”

Section: Fault Mechanism Solutionsmentioning

confidence: 99%

“…The Ston-Slano earthquake sequence, with the mainshock of 5 September, 1996 (M w = 6.0, I max = VIII Medvedev-Sponheuer-Karnik scale, henceforth MSK), is the most important and the largest one in the southern Dalmatia zone, i.e., Dubrovnik epicentral area that occurred since the catastrophic Dubrovnik earthquake of 1667 (epicentral intensity I o = IX MSK). Described in detail by Markušić et al [1] and Herak et al [2], the mainshock was felt about 400 km away, and caused devastation at several localities in the epicentral area, where about 1400 buildings were damaged, of which 474 became uninhabitable [3]. Especially affected was the municipality of Ston.…”

Section: Introductionmentioning

confidence: 99%

“…External Dinarides are intensely folded and faulted as a result of intensive convergence of The earthquake sequence lasted for about a year, with more than 1800 located aftershocks within 50 km from the mainshock's epicentre. Numerical modeling of the aftershocks' rate of occurrence was done by Herak et al [2]. The largest aftershocks occurred on 9 September, 1996 (15:57 UTC, M w = 5.3, I max = VII MSK) and 17 September, 1996 (13:45 UTC, M w = 5.4).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Constraints on Complex Faulting during the 1996 Ston–Slano (Croatia) Earthquake Inferred from the DInSAR, Seismological, and Geological Observations

et al. 2020

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This study, involving remote sensing, seismology, and geology, revealed complex faulting during the mainshock of the Ston–Slano earthquake sequence (5 September, 1996, Mw = 6.0). The observed DInSAR interferogram fringe patterns could not be explained by a single fault rupture. Geological investigations assigned most of the interferogram features either to previously known faults or to those newly determined by field studies. Relocation of hypocentres and reassessment of fault mechanisms provided additional constraints on the evolution of stress release during this sequence. Available data support the scenario that the mainshock started with a reverse rupture with a left-lateral component on the Slano fault 4.5 km ESE of Slano, at the depth of about 11 km. The rupture proceeded unilaterally to the NW with the velocity of about 1.5 km/s for about 11 km, where the maximum stress release occurred. DInSAR interferograms suggest that several faults were activated in the process. The rupture terminated about 20 km away from the epicentre, close to the town of Ston, where the maximum DInSAR ground displacement reached 38 cm. Such a complicated and multiple rupture has never before been documented in the Dinarides. If this proves to be a common occurrence, it can pose problems in defining realistic hazard scenarios, especially in deterministic hazard assessment.