Salt tectonics in the SW Alps (Italy–France): From rifting to the inversion of the European continental margin in a context of oblique convergence

Decarlis, Alessandro; Maino, M.; Dallagiovanna, Giorgio; Lualdi, Alberto; Masini, Emmanuel; Seno, Silvio; Toscani, Giovanni

doi:10.1016/j.tecto.2014.09.003

Cited by 29 publications

(21 citation statements)

References 89 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Instead, open chevron and kink folds are generally associated with a third ductile phase (D3), possibly generating asymmetric dome-and-basin interference patterns [8,10,21,25]. Brittle deformation became dominant since the upper Early Oligocene, when transtensional/transpressional fault systems, which are associated with the rifting of the Liguro-Provençal basin and the Corsica-Sardinia drifting, induced the~50 • Neogene rotation of the Ligurian and internal SW Alps [26][27][28][29][30][31]. The final emplacement of the Helminthoid Flysch nappes is constrained between 34 and 28 Ma by means of zircon (U-Th)/He absolute dating of the basal thrust [20].…”

Section: Geological Settingmentioning

confidence: 99%

Progressive Deformation Patterns from an Accretionary Prism (Helminthoid Flysch, Ligurian Alps, Italy)

2020

View full text Add to dashboard Cite

This paper reports the results of a field-based structural investigation of a well-exposed paleo-accretionary prism, which experienced complex deformation in a low-grade metamorphic setting. Field analyses focused on the description of structural fabrics, with the main emphasis upon parameters like the orientation, style and kinematics of foliations, folds and shear zones. We address the research to the south-westernmost part of the Alpine chain, the Ligurian Alps, where, despite their origin as turbidite sequences deposited into the closing Alpine Tethys Ocean, the Helminthoid Flysch Nappes are presently distributed in the outer part of the chain, above the foreland. The new dataset highlights different deformation patterns related to the different spatial distribution of the flysch units. This regional-scale partitioning of strain is hence associated with progressive deformation within a two-stage geodynamic evolution. Correlations among the different orogenic domains allow the proposal of a kinematic model that describes the motion of the Helminthoid Flysch from the inner to the outer part of the orogen, encompassing the shift from subduction- to collision-related Alpine geodynamic phases.

show abstract

Section: Geological Settingmentioning

confidence: 99%

Progressive Deformation Patterns from an Accretionary Prism (Helminthoid Flysch, Ligurian Alps, Italy)

2020

View full text Add to dashboard Cite

show abstract

“…It is common in foreland basin modeling and fold-and-thrust belt studies to analyze only one side of a doubly vergent orogen (e.g., Decarlis et al, 2014;Ershov et al, 2003;Fillon et al, 2013). However, several studies, mainly based on mechanical modeling, suggest that pro-and retro-wedges interact in accommodating plate convergence (Erdős et al, 2015;Hoth et al, 2007Hoth et al, , 2008Sinclair et al, 2005;Willett et al, 1993).…”

Section: Introductionmentioning

confidence: 99%

Insights Into the Crustal‐Scale Dynamics of a Doubly Vergent Orogen From a Quantitative Analysis of Its Forelands: A Case Study of the Eastern Pyrenees

et al. 2018

View full text Add to dashboard Cite

In natural doubly vergent orogens, the relationship between the pro‐ and retro‐wedges is, as yet, poorly constrained. We present a detailed tectonostratigraphic study of the retro‐wedge of the Eastern Pyrenees (Europe) and link its evolution to that of the pro‐wedge (Iberia) in order to derive insight into the crustal‐scale dynamics of doubly vergent orogens. Based on cross‐section restoration and subsidence analyses, we divide the East Pyrenean evolution into four phases. The first phase (Late Cretaceous) is characterized by closure of an exhumed mantle domain between the Iberian and European plates and inversion of a salt‐rich, thermally unequilibrated rift system. Overall shortening (~1 mm/yr) was distributed roughly equally between both margins over some 20 Myr. A quiescent phase (Paleocene) was apparently restricted to the retro‐wedge with slow, continuous deformation in the pro‐wedge (~0.4 mm/yr). This phase occurred between closure of the exhumed mantle domain and onset of main collision. The main collision phase (Eocene) records the highest shortening rate (~3.1 mm/yr), which was predominantly accommodated in the pro‐wedge. During the final phase (Oligocene), the retro‐wedge was apparently inactive, and shortening of the pro‐wedge slowed (~2.2 mm/yr). Minimum total shortening of the Eastern Pyrenees is ~111 km, excluding closure of the exhumed mantle domain. The retro‐wedge accommodated ~20 km of shortening. The shortening distribution between the pro‐ and retro‐wedges evolved from roughly equal during rift inversion to pro‐dominant during main collision. This change in shortening distribution may be intrinsic to all inverted rift systems.

show abstract

“…The Ligurian Alps are located at the southwestern end of the Western Alps arc, toward the transition with the Northern Apennine (Decarlis et al, ; Maino et al, ; Vanossi, ). They consist of a Variscan basement and of a Permian to Cenozoic sedimentary cover that were originally part of the paleo‐European margin, belonging to the Briançonnais‐Prepiedmont domains (Figures d and b).…”

Section: Geological Settingmentioning

confidence: 99%

Tectono‐thermal Evolution of a Distal Rifted Margin: Constraints From the Calizzano Massif (Prepiedmont‐Briançonnais Domain, Ligurian Alps)

et al. 2017

View full text Add to dashboard Cite

The thermal evolution of distal domains along rifted margins is at present poorly constrained. In this study, we show that a thermal pulse, most likely triggered by lithospheric thinning and asthenospheric rise, is recorded at upper crustal levels and may also influence the diagenetic processes in the overlying sediments, thus representing a critical aspect for the evaluation of hydrocarbon systems. The thermal history of a distal sector of the Alpine Tethys rifted margin preserved in the Ligurian Alps (Case Tuberto‐Calizzano unit) is investigated with thermochronological methods and petrologic observations. The studied unit is composed of a polymetamorphic basement and a sedimentary cover, providing a complete section through the prerift, synrift, and postrift system. Zircon fission track analyses on basement rocks samples suggest that temperatures exceeding ~240 ± 25°C were reached before ~150–160 Ma (Upper Jurassic) at few kilometer depth. Neoformation of green biotite, stable at temperatures of ~350 to 450°C, was synkinematic with this event. The tectonic setting of the studied unit suggests that the heating‐cooling cycle took place during the formation of the distal rifted margin and terminated during Late Jurassic (150–160 Ma). Major crustal and lithospheric thinning likely promoted high geothermal gradients (~60–90°C/km) and triggered the circulation of hot, deep‐seated fluids along brittle faults, causing the observed thermal anomaly. Our results suggest that rifting can generate thermal perturbations at relatively high temperatures (between ~240 and 450°C) at less than 3 km depth in the distal domains during major crustal thinning preceding breakup and onset of seafloor spreading.

show abstract

Salt tectonics in the SW Alps (Italy–France): From rifting to the inversion of the European continental margin in a context of oblique convergence

Cited by 29 publications

References 89 publications

Progressive Deformation Patterns from an Accretionary Prism (Helminthoid Flysch, Ligurian Alps, Italy)

Progressive Deformation Patterns from an Accretionary Prism (Helminthoid Flysch, Ligurian Alps, Italy)

Insights Into the Crustal‐Scale Dynamics of a Doubly Vergent Orogen From a Quantitative Analysis of Its Forelands: A Case Study of the Eastern Pyrenees

Tectono‐thermal Evolution of a Distal Rifted Margin: Constraints From the Calizzano Massif (Prepiedmont‐Briançonnais Domain, Ligurian Alps)

Contact Info

Product

Resources

About