1,721,126 research outputs found
Paolo Scandone: primo Direttore del Dipartimento di Scienze della Terra dell'Università di Pisa, docente e collega
No full textThe contribution first deals with the years of Paolo Scandone’s arrival in Pisa and of his election, in 1981, to the first Direction of the then-established Department of Earth Sciences. This first part is completed with some personal recollections related to his activity as professor in the class of Geologia Regionale and then as colleague until the year of his retiremen
Discussion on ‘Breaking up continents at magma-poor rifted margins: a seismic v. outcrop perspective’
No full textDiscussion on https://doi.org/10.1144/jgs2018-041 (Decarlis et al., 2018
New petrologic and 39Ar/40Ar data on the Palaeozoic metamorphic basement of the Northern Apennines (NW Italy): evidence from surface and subsurface units
No full textFold and shear zone development in a progressive compressional deformation: an example from the Alpi Apuane (NW Tuscany, Italy)
No full textStructural inheritance and style of reactivation at mid-crustal levels: A case study from the Apuane Alps (Tuscany, Italy)
No full textStructural analyses of the geometries and strain patterns of regional-scale folds in the Alpi Apuane, northwest
Tuscany, Italy, show that the analyzed structures formed at mid-crustal conditions during the Oligocene–
Miocene continental subduction of the Adria distal margin, and show evidence of structural inheritance in
terms of: a) minor thrusts derived from fully inverted normal faults, local examples of inversion structures
and their reactivation at mid-crustal depth; b) kilometer-scale variations in facies and thickness changes in
the stratigraphic successions closely related with structural positions within large scale folds; c) formation
of regional recumbent folds by initiation of fold nucleation and buckling on the site of former Jurassic faults
and related lateral layer heterogeneities; d) relationship between rotated fold-segments or cross-folds and
the primary shape of sub-basins, its original fault segmentation and the presence of transfer zones.
The overall data set underline the importance of structural heritage in shaping overall architecture and kinematic
development also in the internal metamorphic zones of orogens
'High-temperature' texture in naturally deformed Carrara marble from the Alpi Apuane, Italy
No full textFrom deformation experiments and numerical modelling, a large type variety of crystallographic preferred orientations (textures) are known for calcite. In contrast, naturally deformed samples usually show the 'low-temperature (LT)'-texture type with only minor texture variations. The 'high-temperature (HT)'-texture type is rarely described and mostly not very well defined. Based on neutron diffraction measurements and a quantitative texture analysis by means of the iterative series expansion method and the texture component model, this study gives evidence for the HT-texture type in a deformed marble from the Alpi Apuane in Italy. The microstructure of the sample shows elongated grains with long/short axis ratios of up to 10:1. The long axes of the grains are oriented parallel to the general direction of transport indicating prolate strain, but no shear sense. From the texture, a shear sense can be deduced that cannot be fully brought in line with the regional deformation and thermal history. The results indicate a larger texture variety of naturally deformed calcite rocks than generally assumed. This should stimulate further systematic texture studies for a better understanding of the texture forming mechanisms and the closely connected understanding of the kinematic significance of textures for the analysis of regional deformation histories. (C) 2002 Elsevier Science Ltd. All rights reserved
"High-Temperature" texture in naturally deformed Calcite marble from the Alpi Apuane, Italy
No full text
The granitoid rocks associated with MORB in the External Liguride Units (Northern Apennine, Italy)
No full textThe Compione Fault: damage zone structural and paleofluid characterization of a segment of the Lunigiana extensional fault systems, Northern Apennines
Get PDFA study of meso- and microstructural features of an exhumed high angle normal fault observed in Carrara marble of
the Alpi Apuane NW Tuscany (Italy) is here presented. The studied fault was formed at shallow crustal depth and related
with the recent deformation history of the Alpi Apuane metamorphic core (Molli et al. 2015, Molli et al., 2016). On the
basis of meso- and microscale deformation features different stages of fault zone evolution were recognized. Stage 1 was
associated with extensional and shear veins now observable in both hangingwall and footwall blocks as part of the
deformation zone developed at decameter-scale. Geochemical data indicate vein-development in a locally closed system
where a “stationary” fluid phase migrates over meter-scale distances (Molli et al., 2011). At stage 2, a localization of the
deformation took place. During this second stage, crystal-plastic deformation affected a millimeter-thick zone along the
main slip surfaces, whereas cataclastic deformation produced a decimeter to meter thick fault core with brecciation and
far-derived fluid channelling leading to significant geochemical alteration of the fault rocks with respect to the protolith
(Molli et al. 2011). Deformation was then localized within ultracataclasite of the fault core where diffusive-mass transfer
dominates the microstructural development (stage 3). The fault history ends with stage 4, associated with a vertical
shortening and development of slickolites at the contact between the main slip surface and fault core and microveins plus
stylolites within the fault core.
The analysis of the studied fault within Carrara marble reveals therefore a switching in the deformation mode in terms
of distributed vs localized and a changing in deformation mechanisms; these features may be associated, following the
most recent experimental work (e.g. Smith et al., 2012), with a “fossil” seismic cycle
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