Limestones from the Tuscan Nappe sequence, northern Apennines, Italy, have been deformed during c... more Limestones from the Tuscan Nappe sequence, northern Apennines, Italy, have been deformed during crustal thickening at temperatures less than 250°C. As part of this deformation, bedding-parallel shear zones have formed within two distinct protoliths: (1) very fine-grained (< 5μm) micritic calcite (with some veins) that comprises the host material and (2) initially coarse-grained vein calcite. Evolution of the shear zones produced extreme grain size reduction in the vein calcite such that at high strains, the grain size distribution and microstructure of host micrite and deformed vein calcite is essentially the same. Although vein calcite in the micrite experiences similar microstructural changes to that of the vein hosted shear zone, indicative of similar deformation conditions, the grain size of the deformed micrite is comparable or slightly larger than the starting material. In terms of the mechanical and microstructural changes, the variation in initial grain size would, at fir...
Alpine Corsica consists of a stack of variably metamorphosed units of continental and Tethys-deri... more Alpine Corsica consists of a stack of variably metamorphosed units of continental and Tethys-derived rocks. It represents an excellent example of high-pressure (HP) orogenic belt, such as the Western Alps, exposed over a small and accessible area. Compared to the Western Alps, the geology of Alpine Corsica is poorly unraveled. During the 1970s–80s, based on either lithostratigraphic or metamorphic field observations, various classifications of the belt have been proposed, but these classifications have been rarely matched together. ...
ABSTRACT The Alpi Apuane represent a large tectonic window within the Northern Apennine in Italy.... more ABSTRACT The Alpi Apuane represent a large tectonic window within the Northern Apennine in Italy. In this area, not only a complete succession of the tectonic units of the Northern Apennine can be studied, but also the structures that result from at least two Alpine deformational events. The rocks of the Alpi Apuane have been deposited from Triassic to Tertiary times on the Hercynian basement of the passive continental margin of the Apulian plate. The sedimentary succession included meta-dolostones, marbles, metacherts, schists, and turbiditic arenites. During late Oligocene more internal units (the Tuscan Nappe together with the overlying Ligurides and Sub- Ligurides) were thrusted over the External Tuscan Domain (Alpi Apuane). The Alpi Apuane stratigraphic sequence was subject to greenschist facies metamorphosis and severe deformation within a crustal scale shear zone. Kilometrescale tight recumbent folds developed during a first deformation event (D1). The successive crustal shortening resulted in a further tightening of folds and the formation of an antiformal stack geometry with a central culmination. This late phase of D1 produced a curving of N–S (Apenninic) trending folds towards an E–W (anti-Apenninic) trend. During Miocene the overthickened antiform underwent gravitational collapse resulting in the refolding of D1 structures producing D2 open and back folds. The studied field area is located in the Eastern Alpi Apuane between Arni and Isola Santa in an area of anti-Apenninic trending D1 folds. The purpose of this study is to contribute to an understanding of 1. how the anti-Apenninic fold trend is developed in the Eastern Alpi Apuane, 2. how the D2 deformational event influenced the D1 folds in the area, and 3. how the anti-Apenninic fold trend developed.
Limestones from the Tuscan Nappe sequence, northern Apennines, Italy, have been deformed during c... more Limestones from the Tuscan Nappe sequence, northern Apennines, Italy, have been deformed during crustal thickening at temperatures less than 250°C. As part of this deformation, bedding-parallel shear zones have formed within two distinct protoliths: (1) very fine-grained (&amp;amp;amp;amp;lt; 5mum) micritic calcite (with some veins) that comprises the host material and (2) initially coarse-grained vein calcite. Evolution of the shear zones
Per. Mineral. (2005), 74,1,117-140 http://go.to/permin I ] PERIODICO di MINERALOGIA established i... more Per. Mineral. (2005), 74,1,117-140 http://go.to/permin I ] PERIODICO di MINERALOGIA established in 1930 An International Journal of MINERALOGY, CRYSTALLOGRAPHY, GEOCHEMISTRY, ORE DEPOSITS, PETROLOGY, VOLCANOLOGY and applied topics ...
Fourth International Conference on Fault and Top Seals, 2015
ABSTRACT Structural architecture and paleofluid evolution of the Tellaro detachment fault (Northe... more ABSTRACT Structural architecture and paleofluid evolution of the Tellaro detachment fault (Northern Apennines, Italy)
In the Cerreto area metamorphic rocks belonging to the basement of the Northern Apennine are expo... more In the Cerreto area metamorphic rocks belonging to the basement of the Northern Apennine are exposed in association with Triassic evaporites and quartzites. The Cerreto basement rocks consist of lenses and plurimetric bodies of amphibolites included in a sequence of metapsammites (biotite and/or muscovite schists). Both metasediments and amphibolites underwent a retrograde evolution starting from an initial medium-pressure amphibolite stage (M1: P ~ 8 kbar, T ~ 650°C) down to greenschist condition. The amphibolites show a well preserved earlier foliation associated with development of green amphibole (aluminotschermakite) + plagioclase + quartz + ilmenite assemblage followed by partial retrograde recrystallization in epidote-amphibolite facies under static conditions and along shear zones (M2: ~ P 4-5 kbar, T ~ 530°C); pre-kinematic garnet porphyroblasts rimmed by amphibole + plagioclase coronas are widespread. Metasediments show a pervasive mylonitic deformation associated with amp...
During the last thirty years, many experimental studies allowed to better understand the main tec... more During the last thirty years, many experimental studies allowed to better understand the main tectonic processes involved in the development of accretionary wedges. Using this approach, the effects of numerous parameters on geometry, deformation mechanisms and faults kinematics have been investigated. More recently, the impact of surface processes has been shown to be major in the development orogenic wedges. Indeed erosion, and sedimentation influence wedge’s dynamics through surface and deep mass transfers (e.g. Davis et al., 1983; Mugnier et al., 1997; Konstantinovskaia & Malavieille, 2005; Cruz et al., 2008). New analogue experiments have been performed at Géosciences Montpellier Laboratory to study the evolution of eroded thrust wedges taking into account specific inherited structures of the downgoing plate. A classical sandbox set up has been improved to allow large shortening and to account for a more realistic geometry of lower plate structures. Thin layers of weak materials...
Limestones from the Tuscan Nappe sequence, northern Apennines, Italy, have been deformed during c... more Limestones from the Tuscan Nappe sequence, northern Apennines, Italy, have been deformed during crustal thickening at temperatures less than 250°C. As part of this deformation, bedding-parallel shear zones have formed within two distinct protoliths: (1) very fine-grained (< 5μm) micritic calcite (with some veins) that comprises the host material and (2) initially coarse-grained vein calcite. Evolution of the shear zones produced extreme grain size reduction in the vein calcite such that at high strains, the grain size distribution and microstructure of host micrite and deformed vein calcite is essentially the same. Although vein calcite in the micrite experiences similar microstructural changes to that of the vein hosted shear zone, indicative of similar deformation conditions, the grain size of the deformed micrite is comparable or slightly larger than the starting material. In terms of the mechanical and microstructural changes, the variation in initial grain size would, at fir...
Alpine Corsica consists of a stack of variably metamorphosed units of continental and Tethys-deri... more Alpine Corsica consists of a stack of variably metamorphosed units of continental and Tethys-derived rocks. It represents an excellent example of high-pressure (HP) orogenic belt, such as the Western Alps, exposed over a small and accessible area. Compared to the Western Alps, the geology of Alpine Corsica is poorly unraveled. During the 1970s–80s, based on either lithostratigraphic or metamorphic field observations, various classifications of the belt have been proposed, but these classifications have been rarely matched together. ...
ABSTRACT The Alpi Apuane represent a large tectonic window within the Northern Apennine in Italy.... more ABSTRACT The Alpi Apuane represent a large tectonic window within the Northern Apennine in Italy. In this area, not only a complete succession of the tectonic units of the Northern Apennine can be studied, but also the structures that result from at least two Alpine deformational events. The rocks of the Alpi Apuane have been deposited from Triassic to Tertiary times on the Hercynian basement of the passive continental margin of the Apulian plate. The sedimentary succession included meta-dolostones, marbles, metacherts, schists, and turbiditic arenites. During late Oligocene more internal units (the Tuscan Nappe together with the overlying Ligurides and Sub- Ligurides) were thrusted over the External Tuscan Domain (Alpi Apuane). The Alpi Apuane stratigraphic sequence was subject to greenschist facies metamorphosis and severe deformation within a crustal scale shear zone. Kilometrescale tight recumbent folds developed during a first deformation event (D1). The successive crustal shortening resulted in a further tightening of folds and the formation of an antiformal stack geometry with a central culmination. This late phase of D1 produced a curving of N–S (Apenninic) trending folds towards an E–W (anti-Apenninic) trend. During Miocene the overthickened antiform underwent gravitational collapse resulting in the refolding of D1 structures producing D2 open and back folds. The studied field area is located in the Eastern Alpi Apuane between Arni and Isola Santa in an area of anti-Apenninic trending D1 folds. The purpose of this study is to contribute to an understanding of 1. how the anti-Apenninic fold trend is developed in the Eastern Alpi Apuane, 2. how the D2 deformational event influenced the D1 folds in the area, and 3. how the anti-Apenninic fold trend developed.
Limestones from the Tuscan Nappe sequence, northern Apennines, Italy, have been deformed during c... more Limestones from the Tuscan Nappe sequence, northern Apennines, Italy, have been deformed during crustal thickening at temperatures less than 250°C. As part of this deformation, bedding-parallel shear zones have formed within two distinct protoliths: (1) very fine-grained (&amp;amp;amp;amp;lt; 5mum) micritic calcite (with some veins) that comprises the host material and (2) initially coarse-grained vein calcite. Evolution of the shear zones
Per. Mineral. (2005), 74,1,117-140 http://go.to/permin I ] PERIODICO di MINERALOGIA established i... more Per. Mineral. (2005), 74,1,117-140 http://go.to/permin I ] PERIODICO di MINERALOGIA established in 1930 An International Journal of MINERALOGY, CRYSTALLOGRAPHY, GEOCHEMISTRY, ORE DEPOSITS, PETROLOGY, VOLCANOLOGY and applied topics ...
Fourth International Conference on Fault and Top Seals, 2015
ABSTRACT Structural architecture and paleofluid evolution of the Tellaro detachment fault (Northe... more ABSTRACT Structural architecture and paleofluid evolution of the Tellaro detachment fault (Northern Apennines, Italy)
In the Cerreto area metamorphic rocks belonging to the basement of the Northern Apennine are expo... more In the Cerreto area metamorphic rocks belonging to the basement of the Northern Apennine are exposed in association with Triassic evaporites and quartzites. The Cerreto basement rocks consist of lenses and plurimetric bodies of amphibolites included in a sequence of metapsammites (biotite and/or muscovite schists). Both metasediments and amphibolites underwent a retrograde evolution starting from an initial medium-pressure amphibolite stage (M1: P ~ 8 kbar, T ~ 650°C) down to greenschist condition. The amphibolites show a well preserved earlier foliation associated with development of green amphibole (aluminotschermakite) + plagioclase + quartz + ilmenite assemblage followed by partial retrograde recrystallization in epidote-amphibolite facies under static conditions and along shear zones (M2: ~ P 4-5 kbar, T ~ 530°C); pre-kinematic garnet porphyroblasts rimmed by amphibole + plagioclase coronas are widespread. Metasediments show a pervasive mylonitic deformation associated with amp...
During the last thirty years, many experimental studies allowed to better understand the main tec... more During the last thirty years, many experimental studies allowed to better understand the main tectonic processes involved in the development of accretionary wedges. Using this approach, the effects of numerous parameters on geometry, deformation mechanisms and faults kinematics have been investigated. More recently, the impact of surface processes has been shown to be major in the development orogenic wedges. Indeed erosion, and sedimentation influence wedge’s dynamics through surface and deep mass transfers (e.g. Davis et al., 1983; Mugnier et al., 1997; Konstantinovskaia & Malavieille, 2005; Cruz et al., 2008). New analogue experiments have been performed at Géosciences Montpellier Laboratory to study the evolution of eroded thrust wedges taking into account specific inherited structures of the downgoing plate. A classical sandbox set up has been improved to allow large shortening and to account for a more realistic geometry of lower plate structures. Thin layers of weak materials...
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