The influence of subsurface geology on the distribution of earthquakes during the 2016‐–2017 Central Italy seismic sequence

Barchi, Massimiliano Rinaldo; Carboni, Filippo; Michele, Maddalena; Ercoli, Maurizio; Giorgetti, C.; Porreca, Massimiliano; Azzaro, Salvatore; Chiaraluce, L.

doi:10.1016/j.tecto.2021.228797

Cited by 40 publications

(42 citation statements)

References 84 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Previously unresolved, the new catalog unambiguously shows that the Mt. Gorzano fault is active and continuous throughout the whole entire crust (Figure 4c), progressively dipping steeper toward the surface where it correlates with the mapped fault trace (Barchi et al., 2021). The detachment zone in this area is again made up of two sub‐horizontal shear faults that are vertically separated by about 1 km (black lines in Figure 4c; see also Figure 2d).…”

Section: Discussionmentioning

confidence: 78%

“…The ST has been proposed to control rupture initiation and arrest of the mainshocks (Barchi et al., 2021; Improta et al., 2019; Tinti et al., 2016), although the Amatrice rupture crossed it. Chiaraluce et al.…”

Section: Discussionmentioning

confidence: 99%

“…The ST has been proposed to control rupture initiation and arrest of the mainshocks (Barchi et al, 2021;Improta et al, 2019;Tinti et al, 2016), although the Amatrice rupture crossed it. Chiaraluce et al (2017) proposed that rheological heterogeneities within the source volume controls slip distribution.…”

Section: Seismic Barriermentioning

confidence: 99%

See 2 more Smart Citations

Fault Planes, Fault Zone Structure and Detachment Fragmentation Resolved With High‐Precision Aftershock Locations of the 2016–2017 Central Italy Sequence

Waldhauser

Michele

Chiaraluce

et al. 2021

Geophysical Research Letters

View full text Add to dashboard Cite

The 2016-2017 earthquake sequence in central Italy has been one of the most vigorous and best recorded seismic events along the Apennine mountain chain. As frequently observed in regions of distributed continental faulting (Walters et al., 2018), the sequence was characterized by a series of large normal faulting earthquakes that span over a period of only a few months. The complex nature of the cascade of multi-segment fault ruptures resembles previous large (e.g., 1980, Irpinia, 1997 Colfiorito, 2009 L'Aquila; see Chiaraluce et al., 2017 and references therein) and smaller sequences (e.g., Sánchez-Reyes et al., 2021;Totaro et al., 2015) along the Apennines, all related to a network of interconnected and highly segmented active normal faults that respond to the present-day extensional stress field and interact with thrust structures inherited from a compressional tectonic phase during the Neogene.

show abstract

Section: Discussionmentioning

confidence: 78%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Fault Planes, Fault Zone Structure and Detachment Fragmentation Resolved With High‐Precision Aftershock Locations of the 2016–2017 Central Italy Sequence

Waldhauser

Michele

Chiaraluce

et al. 2021

Geophysical Research Letters

View full text Add to dashboard Cite

show abstract

“…Near the Norcia mainshock, seismic pro les (Fig. 1) image the geometry of the subsurface structures (see details in 14 ). Here the re ector corresponding to the top of the TE can be traced in the footwall of the M. Vettore fault, the structure that hosted the M w 6.5 earthquake and produced surface breaks 15 .…”

Section: Geology and Seismicity Distributionmentioning

confidence: 99%

“…Close to the Norcia hypocentre the subsurface geology can be schematically represented by carbonates and TE at depths < 4-5 km, TE at depths between 5 and 9 km and acoustic, phyllosilicate-rich basement below 9 km (Fig. 2a and details in 14 ). In this area, the presence of a dense seismic network and the application of improved earthquake detection and location techniques allowed the development of comprehensive earthquake catalogues 10,[19][20][21] .…”

Section: Geology and Seismicity Distributionmentioning

confidence: 99%

On fault vs. off-fault seismicity: the role of rock vs. fault rheology

Collettini

Paola

Barchi

et al. 2022

Preprint

View full text Add to dashboard Cite

Analysis of seismicity can illuminate active fault zone structures but also pervasive deformation occurring within large volumes of the seismogenic zone. Here we show that, for the Mw 6.5 2016–2017 Central Italy seismic sequence, seismicity not only localizes along SW-dipping normal faults, but also occurs within larger volumes of Triassic Evaporites, TE, composed of alternated anhydrites and dolostones. This off-fault and diffuse microseismicity shows a different frequency-magnitude distribution than on-fault seismicity along the structures hosting the largest events. We interpret that, during the sequence, shear strain-rate increase promoted widespread ductile deformation within TE that light-up with diffuse microseismicity. This interpretation is supported by field and laboratory observations showing that TE background ductile deformation is complex and dominated by distributed failure and folding of the anhydrites associated with boudinage fracturing and faulting of dolostones. Our results indicate that ductile crustal deformation can cause off-fault and diffuse microseismicity, which obeys to different scaling laws than on-fault seismicity on structures characterized by elasto-frictional stick-sip behaviour.

show abstract

Lateral Variations of P-Wave Velocity from Deep Borehole Data in the Southern Apennines, Italy

Montone

Mariucci

2023

Pure Appl. Geophys.

View full text Add to dashboard Cite

We have selected 28 deep wells in the Southern Apennine area, most of which are located along and around the Val d’Agri Basin. The Southern Apennines, one of the most seismically active regions of the Italian peninsula, is a NE-verging fold-and-thrust belt characterised by the Meso–Cenozoic Apulia carbonate duplex system overlain by a thick column of Apennine carbonate platform and Lagonegro basin units. These units are unconformably covered by Neogene siliciclastic successions. Among the many Quaternary tectonic basins in the area, the Val d’Agri Basin is the most important intramontane depression, and is bordered by a ~ NW–SE-trending active fault system that represents one of the main seismogenic structures of the region. Moreover, the Val d’Agri Basin is the largest onshore oil field basin in Europe. In this context, we have analysed sonic log records from 28 deep wells and compared them with the corresponding stratigraphy and the other geophysical logs. We have obtained detailed measurements of the P-wave velocity (Vp) for each well from 0 to ~ 6 km depth, and found important lateral variations of Vp over very small distances. From these values, we have retrieved the densities of the main units crossed by the wells and the range of the overburden gradient in this area.

show abstract

The influence of subsurface geology on the distribution of earthquakes during the 2016‐–2017 Central Italy seismic sequence

Cited by 40 publications

References 84 publications

Fault Planes, Fault Zone Structure and Detachment Fragmentation Resolved With High‐Precision Aftershock Locations of the 2016–2017 Central Italy Sequence

Fault Planes, Fault Zone Structure and Detachment Fragmentation Resolved With High‐Precision Aftershock Locations of the 2016–2017 Central Italy Sequence

On fault vs. off-fault seismicity: the role of rock vs. fault rheology

Lateral Variations of P-Wave Velocity from Deep Borehole Data in the Southern Apennines, Italy

Contact Info

Product

Resources

About