The Tuscan successions of the Western sector of the Foglio 289 - Citta di Castello area have been attributed, by means of the new field mapping carried out as part of the CARG Project and related sedimentological-biostratigraphical-petrographical analyses, to the following formations, from the bottom up: Scaglia toscana Fm (Rupelian-Chattian in age, between the NP21-22 and the MNP25b Biozone), Macigno Fm (Chattian, MNP25b Biozone-Aquitanian, MNNId Biozone), Celle Sandstones Fm (Aquitanian-MNNId), Vicchio Marls (Aquitanian-Burdigalian, MNN1d-MNN3b). The Macigno Fm (feldspathic and lithofeldspathic arenites, with a homogeneous fine grained lithics composition-Lm>70%) has been subdivided into three members: the Molin Nuovo Member, the Poggio Belvedere Member and the Lippiano Member. The Celle Sanstones form the stratigraphic top of the Macigno Fm in the western sector of the study area. The Vicchio Marls, lying unconformably over the Lippiano Member and over the Celle Sandstones, are interpreted as a piggy-back deposit. None of the turbiditic siliciclastic deposits cropping out in this area can be correlated with the Cervarola Sanstones Fm of the type area. From a structural point of view the Scaglia toscana, Macigno and Celle Sandstones Fms belong to the Tuscan Nappe, whose emplacement (Middle Burdigalian, about 18 MY ago in absolute chronology) is sealed by the M. S. Maria Tiberina Fm (Late Burdigalian-Late Serravallian in age) belonging to the Western edge of the Umbrian Domain and probably etheropic in origin of the upper part of the Marnoso-Arenacea Fm. The Tuscan Nappe is subdivided into four main Structural Elements (horses). The thrusts related folds have a more Apenninic trend in the inner Elements and a more meridian trend in the outer ones.

This work deals with the Cretaceous-Tertiary Helminthoid flysch successions of the Emilian Apennines and related basal complexes (Mt. Caio, Val Baganza, Solignano, Mt. Venere-Monghidoro and Mt. Cassio Units); it is based on an integrated approach which included stratigraphic, petrographic and structural observations. Detailed stratigraphic sections measured in the various successions evidenced the specific features of the different Flysch formations. The main framework composition analysis of the arenites pointed out a partly 'oceanic' alimentation for the Mr. Caio Flysch Fm; the Mt. Venere-Monghidoro, and Mr. Cassio Flysch Fms have been alimented exclusively by a terrigenous detritus mainly derived from continental basement source areas. The heavy mineral assemblage of the Mt. Caio Flysch Fm is characterized by picotite, that of the Mt. Venere-Monghidoro, Solignano and Mt. Cassio Flysch Fms commonly contains straurolite, garnet and chloritoid, generally considered to be typical products of the Adriatic continental margin. The calcareous nannofossils biostratigraphy indicated that the flysch sedimentation started during the Late Campanian and ended between the Paleocene (Mt. Cassio Flysch Fm and Mt. Venere-Monghidoro Fms) and the Middle Eocene (Mt. Caio Flysch Fm). We propose a schematic paleogeographic restoration for the External Ligurian Domain which implies a more internal position For the Mt. Caio succession and a more external one for the Mt. Venere-Monghidoro and Mt. Cassio successions. The Helminthoid flyschs sedimented after and during deformation and subduction phases in perched and fore-are basins partly overlying the marginal part of the Adriatic plate. The External Ligurian nappes' stacking consists, in the study area, from the bottom, of the following units: Caio Unit, Val Baganza Ophiolitic Unit, Monghidoro Unit, Cassio Unit. This pile of thrust-nappes, sealed by the Epiligurian succession, has been already realized before Late Eocene. In our opinion it was generated by a frontal west-verging frontal accretion process (offscraping), which let the: flysch successions remain, in this phase, quite undeformed. This westverging thrusting phase, starting from the Middle-Late Eocene, has been followed by an important folding event which generated striking hectometric and kilometric 'Apenninic' reverse folds, sometimes associated with NE-verging thrust surfaces. The Oligocene and post-Oligocene evolution is characterized by a block-translation of the Ligurian staking over the Subligurian, Tuscan and Umbrian Domains, associated with a new generation of minor thrusts and thrust related Apenninic folds. (C) 2000 Editions scientifiques et medicales Elsevier SAS.

The high Reggio Emilia-Parma Apennines is one of the more classic and interesting areas of the Apenninic chain. The outcropping tectonic units are the following from the bottom: - The Tuscan Nappe. It consists of an Adriatic-type sedimentary sequence starting from the Upper Trias and reaching the Aquitanian. It begins with quartzites and evaporites (Upper Trias), followed upward by marine calcareous and marly formations (Jurassic and Early Cretaceous in age) sedimented in a contest of mechanical and thermal subsidence. The sequence is closed by Upper Cretaceous-Tertiary shales (the Scaglia toscana Fm) and by an Upper Oligocene-Aquitanian arenaceous flysch (the Macigno Fm) which represents a typical foredeep deposit. - The Modino Unit (Modino-Pievepelago Sub-Unit). It is formed by a basal tectonic melange of and Sub-Ligurian origin and by a terrigenous piggy-back slope and basin succession, Bartonian-Aquitanian in age. - The Cervarola succession. It consists of Aquitanian-Burdigalian marly and arenaceous sediments (slope marls, basinal turbidites and pebbly sandstones). It sedimented, East of the Apuane Alps, over the Modino Unit during the outwards movement of the latter. In Burdigalian time the Cervarola succession was overthrust by the Ventasso Sub-Unit.- The Ventasso Sub-Unit. It is formed by a sedimentary succession similar to that of the Modino Unit. - The Canetolo Sub-Ligurian Unit. It is formed by an Upper Coniacian-Upper Oligocene succession sedimented over the Adriatic continental margin. in an intermediate position between the and the Tuscan Domain. - The External Units (Caio and Ophiolitic Units, the latter limited to a small area in the NE corner of the map). The Caio Unit is made up of a shaly-calcareous basal (Lower Cretaceous?- Campanian) and by a Helminthoid flysch (Campanian-Maastrichtian). Both the basal and the flysch are alimented by continental Adriatic source-areas and by the oceanic ophiolitic lithosphere. Large masses of Triassic evaporites and quartzites (Scaglie del Secchia) are included, North-East of the Tuscan Nappe front, in the basal part of the allochthonous, mainly in the Ventasso Sub-Unit. They are interpreted as tectonic slices pulled away from mega-extensional structures (in particular the extensional structure of the Cerreto Pass) and pushed outwards by the allochthonous units. The general setting of the Reggio Emilia Apennines is fairly similar to that of adjacent sectors. The evolution of the units is the expression of several extensional (Jurassic) and compression-al phases (Cretaceous and Tertiary). The main compressional in the Domain is the Ligurian phase pre-Upper Eocene in age and, in our opinion, characterized by an Alpine vergence. Starting from the Upper Eocene-Lower Oligocene the compressive deformation became Est-verging and progressively migrated outwards, as it is well documented by the closure times of the turbiditic sedimentation in the foredeep and piggy-back basins. The Tuscan Nappe has been affected by an anchizonal deformation characterized by a slaty cleavage in the argillitic layers and by a spaced or pressure-solution cleavage in the more resistent ones. The uppermost successions (M. Modino, Cervarola, Canetolo and successions) are non-metamorphic and generally characterized by a brittle-ductile deformation, without a pervasive cleavage. The Reggio Emilia Apennines acquired the features of a fold and thrust belt during the Oligo-Miocene phases. The general structure derived from these phases can be compared with that of a duplex, whose roof thrust corresponds with the basis of the Canetolo Unit and whose floor thrust can be supposed within the Tuscan-Umbrian evaporites. The horses of the duplex are well represented in the chain by the structures of the Tuscan Nappe and of the M. Modino-M. Cervarola complex (fault-propagation folds and related thrusts).

Other| January 01, 1975 La nappe de Canetolo G. Plesi G. Plesi Author Search for other works by this author on: GSW Google Scholar Bulletin de la Société Géologique de France (1975) S7-XVII (6): 979–983. https://doi.org/10.2113/gssgfbull.S7-XVII.6.979 Article history first online: 03 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation G. Plesi; La nappe de Canetolo. Bulletin de la Société Géologique de France 1975;; S7-XVII (6): 979–983. doi: https://doi.org/10.2113/gssgfbull.S7-XVII.6.979 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyBulletin de la Société Géologique de France Search Advanced Search This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.