scholarly journals Connecting seismically active normal faults with Quaternary geological structures in a complex extensional environment: The Colfiorito 1997 case history (northern Apennines, Italy)

Tectonics ◽  
2005 ◽  
Vol 24 (1) ◽  
pp. n/a-n/a ◽  
Author(s):  
L. Chiaraluce ◽  
M. Barchi ◽  
C. Collettini ◽  
F. Mirabella ◽  
S. Pucci
Keyword(s):  
Case History ◽  
Northern Apennines ◽  
Normal Faults ◽  
Geological Structures

scholarly journals Applicability of the dipole-dipole method for structural studies: examples from the Northern Apennines

1998 ◽  
Vol 41 (3) ◽  
Author(s):  
M. Giudici ◽  
L. Alfano
Keyword(s):  
Northern Apennines ◽  
Structural Studies ◽  
Geological Structures ◽  
Vertical Electrical Soundings ◽  
North East ◽  
Field Activity ◽  
Electrical Soundings ◽  
Surrounding Areas

We present some results of a geoelectrical investigation program conducted in the Northern Apennines, namely in the Val d'Aveto and Bobbio window and surrounding areas. Field activity included the execution of more than 50 vertical electrical soundings with continuous polar dipole-dipole spread. We image the geometries of some deep geological structures; in particular we found a resistive background, whose resistivity is different along the geoelectrical profiles. In our interpretation the resistive background consists of subligurid and tuscan units underlying the alloctone Ligurid units in the area surrounding the Val d'Aveto and Bobbio window. The resistive background was not found, at least at the same depths, toward north-east. Therefore, the geoelectrical survey revealed the position of the front of the subligurid and Tuscan nappes toward the plain for a depth of about one kilometer.

scholarly journals Filling Materials in Brittle Structures as Indicator of Cenozoic Tectonic Events in Southeastern Brazil

2020 ◽  
Vol 43 (2) ◽  
Author(s):  
Salomão Silva Calegari ◽  
Thaís Ruy Aiolfi ◽  
Mirna Aparecida Neves ◽  
Caroline Cibele Vieira Soares ◽  
Rodson De Abreu Marques ◽  
...  
Keyword(s):  
Manganese Oxides ◽  
Southeastern Brazil ◽  
Normal Faults ◽  
Mineral Formation ◽  
Mineral Precipitation ◽  
Geological Structures ◽  
Weathering Processes ◽  
Mineralogical Association ◽  
Filling Materials ◽  
Tectonic Events

The filling materials in brittle structures can provide useful information about the Cenozoic evolution developed over proterozoic terrains. When these materials are affected by faults, they record deformation phases that can be determined chronologically and, in the occurrence of lateritic materials, it is possible to infer the paleoenvironmental conditions during the mineral formation. This work aimed to identify crystalline phases of brittle structure filling materials and to propose evolutionary interpretations for Cenozoic tectonic reactivation based on literature data. The study area is located in the Southern part of the Espírito Santo State, near the Brazilian Southeastern Continental Margin, where proterozoic geological structures have been reactivated since the mesozoic rift phase, up to the Holocene. The mineral assemblage found in the filling materials includes primary minerals such as quartz, muscovite, microcline, rutile, titanite, and bannisterite; and the weathering minerals such as kaolinite, illite, hematite, goethite, hydrobiotite, lithiophorite and, birnessite. The mineralogical association found in the filling materials denotes the action of fluid phases with mineral precipitation at the brittle discontinuities during the weathering processes that occurred during the Cenozoic, probably between the Miocene and the Pleistocene. The faults, which striations are marked on the filling materials, originated after (in the case of the manganese oxides) or during (in the case of the illite) the mineral formation, indicating that the maximum age of these faults is in the Miocene. The origin of the brittle structures that affected the filling materials studied here is linked to the uplifting of the Continental Brazilian Margin, when ancient geological structures were reactivated as normal faults due to the local action of an extensional regime.

The development and behaviour of low-angle normal faults during Cenozoic asymmetric extension in the Northern Apennines, Italy

2006 ◽  
Vol 28 (2) ◽  
pp. 333-352 ◽  
Author(s):  
C. Collettini ◽  
N. De Paola ◽  
R.E. Holdsworth ◽  
M.R. Barchi
Keyword(s):  
Northern Apennines ◽  
Normal Faults

Structural characterization of the wedge - top Epiligurian Units in the framework of the Northern Apennines tectonic evolution (northern Italy)

2021 ◽  
Author(s):  
Francesca Stendardi ◽  
Gianluca Vignaroli ◽  
Giulio Viola
Keyword(s):  
Tectonic Evolution ◽  
Middle Eocene ◽  
Sedimentary Cover ◽  
Northern Apennines ◽  
Coarse Grained ◽  
Normal Faults ◽  
Accretionary Wedge ◽  
Deformation Bands ◽  
Deformation Structures ◽  
Emilia Romagna Region

<p>The Northern Apennines are an accretionary wedge formed in response to the Late Cretaceous-Eocene closure of the Ligurian-Piedmont ocean and the subsequent Oligocene-Miocene convergence and collision between Africa and Europe. The wedge is formed by a stack of different paleogeographic units which, from the innermost to the outermost and from top to bottom, are: (i) the Ligurian Domain (formed by Jurassic ophiolites and their Cretaceous-to-Paleocene sedimentary cover); (ii) the Sub-Ligurian Domain (Paleocene-to-lower Miocene deep marine sediments and turbidites); (iii) the Tuscan-Umbria-Marche Domain (mostly including Jurassic-to-Oligocene platform and basinal carbonate successions, overlain by Miocene-Pliocene turbidites). The wedge is shaped by WNW-ESE-striking and SW-dipping thrusts, accommodating a general northeastward tectonic transport. Atop of the deformed Ligurian Domain there occur the Epiligurian Units, which consist of middle Eocene-upper Miocene bathyal to shallow-water siliciclastic deposits infilling wedge-top basins. These Units presently fill in separate basins with poor lateral interconnectivity due to erosion and deformation. Since the Miocene, thrusting toward the (eastern) orogenic foreland occurred simultaneously with extension in the (western) hinterland domain, causing the formation of NW-SE-striking normal faults. Presently, focal mechanisms of the stronger earthquakes constrain dominant thrusting associated with NE-SW regional shortening, whereas the extensional regime controls the seismicity along the axial portion of the wedge. This recently launched study aims to better characterize the deformation structures affecting the Epiligurian Units in the internal and external sectors of the Northern Apennines (Emilia-Romagna Region) with the goal to provide a comprehensive syn-to-post accretion evolutionary scenario for these shallow basins. In particular, deformation structures affecting these wedge-top sequences of the inner (southwestern) side of the wedge are being studied by their systematic geometric and kinematic multiscalar and multitechnique characterization. Top-to-the NE, WNW-ESE-striking thrusts/reverse faults, dipping moderately to SSW are defined by planar slip surfaces associated with thin clastic damage zones. Top-to-the SE, ENE-WSW-striking thrusts/reverse faults, are instead generally devoid of well-developed damage zones. These contractional faults are systematically cut by NW-SE and NE-SW-striking normal and oblique faults systems, characterized by mutually intersecting fault planes accommodating centimetric to decimetric throws. Associated with the extensional structures occur widespread cataclastic and disaggregation deformation bands. They are found as either single bands or clusters, cutting across upper Eocene coarse-grained sandstones. Our preliminary results show that the Epiligurian Units experienced a complex tectonic evolution, including NNE-SSW shortening followed by NE-SW extension. The structural record of these wedge top basins is useful to infer the kinematics and rate of wedge build up and tearing down during the progressive evolution of the continental collision. The Epiligurian Units can thus be considered as useful gages of the deformation history of the Northern Apennines wedge, with noteworthy implications on its current seismotectonic setting.</p>

Late evolution of the inner Northern Apennines from the structure of the Monti del Chianti-Monte Cetona Ridge (Tuscany, Italy)

2021 ◽  
Author(s):  
Andrea Brogi
Keyword(s):  
Middle Miocene ◽  
Sedimentary Basins ◽  
Northern Apennines ◽  
Normal Faults ◽  
Tyrrhenian Sea ◽  
Scientific Debate ◽  
Marine Deposits ◽  
Accommodation Space ◽  
Tectonic Events ◽  
Late Evolution

<p>The Neogene and Quaternary tectonic evolution of the inner Northern Apennines (i.e southern Tuscany and northern Tyrrhenian Sea), as well as its crustal features (i.e. low crustal thickness, Neogene-Quaternary magmatism, widespread geothermal anomalies, lateral segmentation of the stacked tectonic units, extensive deep sedimentary basins), are framed in different geodynamic scenarios: compressional, extensional or both, pulsing. Consequently, the basin and range structure that characterises the northern Tyrrhenian Sea and southern Tuscany is considered as a consequence of (i) out-of-sequence thrusts and related thrust-top-basins, (ii) polyphased normal faulting that formed horst and graben structures or (iii) a combination of both. This paper provides a new dataset from a sector of the eastern inner Northern Apennines (i.e. Monti del Chianti - Monte Cetona ridge) contributing to this scientific debate. New fieldwork and structural analysis carried out in selected areas along the ridge allowed to define the chronology of the main tectonic events on the basis of their influence on the marine and continental sedimentation. The dataset supports for early Miocene - (?) Serravallian in-sequence and out-of-sequence thrusting. Thrusting produced complex staking patterns of Tuscan and Ligurian Units. Extensional detachments developed since later middle Miocene and controlled the Neogene sedimentation in bowl-shaped structural depressions, later dissected by normal faults enhancing the accommodation space for Pliocene marine deposits in broad NNW-trending basins (Siena-Radicofani and Valdichiana Basins). In this perspective, no data supports for active, continuous or pulsing, compressional tectonics after late Serravalian. As a result, in the whole inland inner Northern Apennines the extensional tectonics was continuously active at least since middle Miocene and controlled the basins development, magmatism and structure of the crust and lithosphere.</p>

scholarly journals From accretion to exhumation in a fossil accretionary wedge: a case history from Gottero unit (Northern Apennines, Italy)

2004 ◽  
Vol 17 (1) ◽  
pp. 41-53 ◽  
Author(s):  
Michele Marroni ◽  
Francesca Meneghini ◽  
Luca Pandolfi
Keyword(s):  
Case History ◽  
Northern Apennines ◽  
Accretionary Wedge
Sign in / Sign up

Export Citation Format

Share Document