From outcrop to subsurface model—Large-scale fractured zones in Apulian platform carbonates (Maiella Mountains, Central Apennines, Italy)

Abstract Several orogenic belts exhibit regional-scale anticlines characterized by prominent faults in their crestal/forelimb zone. These faults are also a common feature in the Neogene fold-and-thrust belt of the Apennines, where they have been contrastingly interpreted as younger-on-older thrust faults, large-scale strike-slip faults, and pre- or syn-thrusting normal faults. In this study, we analysed a NW–SE-trending fault (Montagna dei Fiori Fault) that affects the hinge-zone/forelimb of the Montagna dei Fiori Anticline. This fold is the outermost exposed contractional structure within the Pliocene–Quaternary antiformal stack of the outer Central Apennines. The integration of stratigraphic and structural data collected during a field geological survey enabled us to reconstruct a multiphase reactivation and deformation along the Montagna dei Fiori Fault. From the novel field data, a different interpretation for the evolution of the Montagna dei Fiori Fault is proposed. The fault originated as a Late Cretaceous – middle Miocene, NE-dipping, Dinaric up-thrust and was later reactivated, displaced and rotated during Pliocene Apennine thrusting and related folding, until assuming a present-day SW-dipping attitude with an apparent normal fault character. This newly proposed Dinaric origin of the Montagna dei Fiori structure is compared with an analogous subsurface example of a Palaeogene–Quaternary structure imaged by seismic reflection profile in the Adriatic foreland. The outcome of this combined field and subsurface investigation provides new elements to unravel the complex evolution of the Apennine thrust belt that developed at the expense of a previously deformed foreland, ahead of the advancing Dinaric chain.

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Diffuse mantle upwelling and melts accumulation beneath the Italian Apennines.

10.5194/egusphere-egu2020-11320 ◽

2020 ◽

Author(s):

Irene Bianchi ◽

Claudio Chiarabba ◽

Pasquale De Gori ◽

Nicola Piana Agostinetti

Keyword(s):

Large Scale ◽

Receiver Function ◽

Mantle Structure ◽

Mantle Upwelling ◽

Central Apennines ◽

Data Set ◽

The North ◽

Italian Apennines ◽

Velocity Zone ◽

Low Shear

The focus of this study is the mantle structure beneath the Apennines, and aims to understanding how deep processes are connected to shallow deformations. We present new observations from a rich receiver function data set from stations located along the North and Central Apennine chain, and use it for comparison and to strengthen the observations of previous seismic tomography images. The two methodologies define a low shear wave velocity zone (decrease of Vs in the order of 5%) and an increase of Vp/Vs (about 3%) in the shallow mantle between 50 and 90 km depth beneath the orogenic belt. The low Vs melt zone is not restricted to the mantle beneath the Quaternary volcanic areas, as previously thought, but is detected under the whole central Apennines suggesting future broad effects on a large scale.&#160; Our interpretation of the teleseismic RFs and tomography, reveals consistently a diffuse mantle upwelling beneath the Apennines, and we hypothesize that slab-derived fluids might interact with the sub-lithospheric mantle generating melts that accumulate at the top of the mantle feeding post-collisional extension. This mechanism can be potentially applied to other cases of extension that spread over wide continental regions.

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The upper crustal geological and structural setting in the area of the 2016-2018 Central Apennines seismic sequence. From subsurface modeling to seismotectonics.

10.5194/egusphere-egu2020-19316 ◽

2020 ◽

Author(s):

Francesco Emanuele Maesano ◽

Mauro Buttinelli ◽

Lorenzo Petracchini ◽

Chiara D'Ambrogi ◽

Davide Scrocca ◽

...

Keyword(s):

Large Scale ◽

Structural Complexity ◽

Seismic Hazard Assessment ◽

Strong Impact ◽

Large Set ◽

Seismic Sequence ◽

Central Apennines ◽

Tectonically Active ◽

Mountain Chain ◽

Inherited Faults

Central Apennines (Italy) is a young and tectonically active mountain chain characterized by a high structural complexity where structures related to various tectonic phases are interacting with each other leading to the reactivation of inherited structures and/or to the segmentation of newly formed ones with a strong impact on the current seismotectonics of the area.In this context, the surface geological and coseismic observations cannot always be extrapolated straightforward to depth and need to be interpreted in the context of the general upper crustal deformation history.These considerations apply also to the area struck by the 2016-2018 Central Apennines seismic sequence where the activation of both single faults and complex fault systems has been observed.In the framework of the RETRACE-3D project, we present a comprehensive 3D geological model derived from the interpretation of a large set of underground data acquired for hydrocarbons explorations and we discuss the implication of this geological reconstruction for the seismotectonics of the area by comparing our results with the coseismic observation.Our results primarily show that, although the area is currently affected by an extensional tectonic regime, the main architecture of this portion of the chain is still dominated by previous compressional large-scale structures with widespread evidence of segmentation, reactivation and even inversion of various sets of inherited faults.These results pose new points of discussion on information and input data needed to understand the seismogenesis in young and complex mountain chains, such as the Central Apennines, and strongly impact on the consequent seismic hazard assessment study.

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Tectonic history of a segment of the Pelagonian zone, northeastern Greece

Canadian Journal of Earth Sciences ◽

10.1139/e81-107 ◽

1981 ◽

Vol 18 (7) ◽

pp. 1111-1126 ◽

Cited By ~ 19

Author(s):

Damian Nance

Keyword(s):

Large Scale ◽

Root Zone ◽

Regional Metamorphism ◽

Late Eocene ◽

Metamorphic Rocks ◽

Tectonic History ◽

History Of ◽

Ophiolitic Rocks ◽

Platform Carbonates ◽

Pelagonian Zone

Continental metamorphic rocks and ophiolitic bodies within the Pelagonian zone of the Hellenides in the Livadi area, northeastern Greece, show repeated periods of deformation that accompany thermal events of Early Cretaceous and possibly Late Eocene age. Structures associated with the earlier deformation indicate thrusting towards the northeast accompanying regional metamorphism of upper greenschist to lower amphibolite facies. Later structures and a retrogression to lower greenschist facies associated with emplacement of the Livadi ophiolitic rocks into their present position are likewise attributed to northeast-directed thrusting and probably accompanied the allochthonous movement of the Pelagonian basement over the Mesozoic platform carbonates of Mt. Olympos.Emplacement vectors of northeast polarity are inconsistent with tectonic models of the Hellenides involving large-scale southwestward obduction of Mesozoic ophiolites from a single ocean located northeast of the Pelagonian zone. Tectonic models involving the converging emplacement of Mesozoic ophiolites from two oceans lying northeast and southwest of the Pelagonian zone are more compatible with the observed structures, the latter ocean providing a potential root zone for the deformed ophiolitic rocks at Livadi.The orientation of minor structures associated with thrusting that postdates the emplacement of the Livadi ophiolitic rocks is consistent with movement from north to south.

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Some comments about observations and image processing of comet 29P/Schwassmann-Wachmann 1

International Astronomical Union Colloquium ◽

10.1017/s0252921100031493 ◽

1999 ◽

Vol 173 ◽

pp. 243-248

Author(s):

D. Kubáček ◽

A. Galád ◽

A. Pravda

Keyword(s):

Image Processing ◽

Large Scale ◽

Harvard College ◽

Oak Ridge ◽

Large Scale Structures ◽

Short Period Comet ◽

Short Period ◽

Scale Structures ◽

Harvard College Observatory ◽

Period Comet

AbstractUnusual short-period comet 29P/Schwassmann-Wachmann 1 inspired many observers to explain its unpredictable outbursts. In this paper large scale structures and features from the inner part of the coma in time periods around outbursts are studied. CCD images were taken at Whipple Observatory, Mt. Hopkins, in 1989 and at Astronomical Observatory, Modra, from 1995 to 1998. Photographic plates of the comet were taken at Harvard College Observatory, Oak Ridge, from 1974 to 1982. The latter were digitized at first to apply the same techniques of image processing for optimizing the visibility of features in the coma during outbursts. Outbursts and coma structures show various shapes.

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Evolution of Large-Scale Coronal Structures

International Astronomical Union Colloquium ◽

10.1017/s0252921100024945 ◽

1994 ◽

Vol 144 ◽

pp. 29-33

Author(s):

P. Ambrož

Keyword(s):

Magnetic Field ◽

Field Line ◽

Large Scale ◽

Coronal Magnetic Field ◽

Source Surface ◽

Solar Cycles ◽

Characteristic Relationship ◽

The Magnetic Field ◽

Coronal Structures

AbstractThe large-scale coronal structures observed during the sporadically visible solar eclipses were compared with the numerically extrapolated field-line structures of coronal magnetic field. A characteristic relationship between the observed structures of coronal plasma and the magnetic field line configurations was determined. The long-term evolution of large scale coronal structures inferred from photospheric magnetic observations in the course of 11- and 22-year solar cycles is described.Some known parameters, such as the source surface radius, or coronal rotation rate are discussed and actually interpreted. A relation between the large-scale photospheric magnetic field evolution and the coronal structure rearrangement is demonstrated.

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Large-scale Motion of Solar Filaments

International Astronomical Union Colloquium ◽

10.1017/s0252921100064502 ◽

2000 ◽

Vol 179 ◽

pp. 205-208

Author(s):

Pavel Ambrož ◽

Alfred Schroll

Keyword(s):

Magnetic Flux ◽

Proper Motion ◽

Time Scale ◽

Large Scale ◽

Accuracy Of Measurements ◽

Solar Filaments ◽

General Movement ◽

Scale Motion ◽

Velocity Scatter

AbstractPrecise measurements of heliographic position of solar filaments were used for determination of the proper motion of solar filaments on the time-scale of days. The filaments have a tendency to make a shaking or waving of the external structure and to make a general movement of whole filament body, coinciding with the transport of the magnetic flux in the photosphere. The velocity scatter of individual measured points is about one order higher than the accuracy of measurements.

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