Analysis and interpretation of Landsat synthetic stereo pair for the detection of active fault zones in the Abruzzi Region (central Italy)

On September 13, 1986, a shallow earthquake (Ms=6.2) struck the city of Kalamata and the surrounding areas (SW Peloponnese, Greece) resulting in 20 fatalities, over 300 injuries, extensive structural damage and many earthquake environmental effects (EEE). The main shock was followed by several aftershocks, the strongest of which occurred two days later (Ms=5.4). The EEE induced by the 1986 Kalamata earthquake sequence include ground subsidence, seismic faults, seismic fractures, rockfalls and hydrological anomalies. The maximum ESI 2007 intensity for the main shock has been evaluated as IXESI 2007, strongly related to the active fault zones and the reactivated faults observed in the area as well as to the intense morphology of the activated Dimiova-Perivolakia graben, which is a 2nd order neotectonic structure located in the SE margin of the Kalamata-Kyparissia mega-graben and bounded by active fault zones. The major structural damage of the main shock was selective and limited to villages founded on the activated Dimiova-Perivolakia graben (IXEMS-98) and to the Kalamata city (IXEMS-98) and its eastern suburbs (IXEMS-98) located at the crossing of the prolongation of two major active fault zones of the affected area. On the contrary, damage of this size was not observed in the surrounding neotectonic structures, which were not activated during this earthquake sequence. It is concluded that both intensity scales fit in with the neotectonic regime of the area. The ESI 2007 scale complemented the EMS-98 seismic intensities and provided a completed picture of the strength and the effects of the September 13, 1986, Kalamata earthquake on the natural and the manmade environment. Moreover, it contributed to a better picture of the earthquake scenario and represents a useful and reliable tool for seismic hazard assessment.

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A Proposition for Geodetic Recording of Active Fault Zones

Geologija ◽

10.5474/geologija.2007.030 ◽

2007 ◽

Vol 50 (2) ◽

pp. 445-454 ◽

Cited By ~ 1

Author(s):

Ladislav Placer ◽

Božo Koler

Keyword(s):

Active Fault ◽

Fault Zones

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CONTEMPORARY GEODYNAMICS OF THE GAROMAI ACTIVE FAULT (SAKHALIN ISLAND)

Geodynamics & Tectonophysics ◽

10.5800/gt-2019-10-2-0426 ◽

2019 ◽

Vol 10 (2) ◽

pp. 561-567

Author(s):

N. F. Vasilenko ◽

A. S. Prytkov

Keyword(s):

Fault Zone ◽

Active Fault ◽

Surface Deformation ◽

Fault Zones ◽

Sakhalin Island ◽

Tectonic Activity ◽

Relative Deformation ◽

Survey Period ◽

Potential Threat ◽

Deformation Processes

In the northern Sakhalin Island, the tectonic activity of the fault zones is a potential threat to the industrial infrastructure of the petroleum fields. Recently, the background seismicity has increased at the Hokkaido‐Sakhalin fault that consists of several segments, including the Garomai active fault. In the studies of the regional deformation processes, it is important not only to analyze the seismic activity, but also to quantitatively assess the dynamics of deformation accumulation in the fault zones. In order to study the contemporary geodynamics of the Garomai fault, a local GPS/GLONASS network has been established in the area wherein trunk oil and gas pipelines are installed across the fault zone. Based on the annual periodic measurements taken in 2006–2016, we study the features of surface deformation and calculate the rates of displacements caused by the tectonic activity in the fault zone. During the survey period, no significant displacement of the fault wings was revealed. In the immediate vicinity of the fault zone, multidirectional horizontal displacements occur at a rate up to 1.6 mm/yr, and uplifting of the ground surface takes place at a rate of 3.4 mm/yr. This pattern of displacements is a reflection of local deformation processes in the fault zone. At the western wing of the fault, a maximum deformation rate amounts to 1110–6 per year. The fault is a boundary mark of a transition from lower deformation rates at the eastern wing to higher ones at the west wing. In contrast to the general regional compression setting that is typical of the northern Sakhalin Island, extension is currently dominant in the Garomai fault zone. The estimated rates of relative deformation in the vicinity of the Garomai fault give grounds to classify it as ‘hazardous’.

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Active Fault Systems in the inner North West Apennines: an updated view

10.5194/egusphere-egu21-1473 ◽

2021 ◽

Author(s):

Giancarlo Molli ◽

Rick Bennett ◽

Jacques Malavieille ◽

Enrico Serpelloni ◽

Fabrizio Storti ◽

...

Keyword(s):

Active Fault ◽

Central Italy ◽

Structural Features ◽

Structural Studies ◽

Data Set ◽

Structural Domains ◽

North West ◽

Fault Systems ◽

Internal Fault ◽

Fault Characterization

As part of an ongoing project of mapping, structural studies and fault characterization we present an updated tectonic scheme and data set for the active fault systems that shaped the inner portion of the Apennines north of the Arno river. Geomorphology, stratigraphy of Plio-Quaternary sediments, GPS data, historical and instrumental seismicity have been reviewed and combined with structural studies to define the neotectonic history of the investigated region. Within the studied area, first-order physiographic and structural features allow to define different structural domains related to a set of ranges with a dominant NW-SE direction separated by intramontane or continental/marine morphotectonic depressions of the Lunigiana, Garfagnana, Lucca-Mt.Albano, La Spezia-Carrara and the off-shore Viareggio basin. The main boundary faults and internal fault segments of the different structural domains were described while the Plio-Quaternary sedimentary records has been used to constrain their long to short term deformation and rates, with the aim to improve current Italian catalogues - DISS (INGV) and Ithaca (ISPRA) - with some utilities for the seismic microzonation local projects. Moreover, our work aims to draw the attention of the scientific community to the seismotectonics of a region in which the seismic hazard is largely considered medium to low despite the occurrence, one century ago, of one of the most destructive earthquakes that have struck the Italian peninsula, the 1920 Fivizzano EQ, with an estimated Mw 6.5 similar to the main shock of the 2016 Central Italy seismic sequence.&#160;

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