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In the Valmala sector of the southern Dora Maira Massif (Western Alps), two different eclogite- and blueschist-facies units (i.e. the Rocca Solei and Dronero units, respectively), are separated by a shear zone (i.e. the Valmala Tectonic Unit), which peculiarly consists of mixed slices of ophiolitic and continental rocks. A detailed geological map at 1:10,000 scale allowed to point out that the tectonic slices within the Valmala Tectonic Unit consist of 'native' rock slices wrenched from the overlying Dronero Unit, and 'exotic' rocks likely sourced from other units of the Dora Maira and from a continental margin and an oceanic basin. On the contrary, rock slices sourced from the underlying Rocca Solei Unit are lacking. The overall tectonic stack results after an early subduction-related deformation phase (i.e. the D1), and the pervasive overprinting of two subsequent exhumation-related deformation phases (i.e. the D2 and D3). The Valmala Tectonic Unit is inferred to have played a role in decoupling the southern Dora Maira Massif during subduction, and/or in driving exhumation of the ultra-high pressure rocks occurring in the adjoining Brossasco-Isasca Unit. [ABSTRACT FROM AUTHOR]

Depending on its chemical and mineralogical composition, the serpentinite represents a peculiar rocky material, which plays a significant role in influencing pedogenetic weathering, vegetation ecology, geo-mechanical and tectonic processes, as well as gravitational slope failure. In serpentinite-bearing environments the response to gravitational stress is more effective than in other rock types. In the Monviso meta-ophiolite Complex (Western Alps), a close relation between landsliding and serpentinite rock occurrences is particularly evident. Our geological map (), at a scale 1:10,000, illustrates the geology and geomorphological features of the Pui-Orgiera giant (2.98 km2) complex landslide, located on the southern slope of the Monviso Massif. This map clearly documents that the characteristics and kinematics of the landslide are closely associated to the anomalous thickening and widening increase of the Baracun Shear Zone, a remnants of an intra-oceanic detachment fault which separates serpentinite and meta-intrusives from metabasalt and metasediments of the Monviso meta-ophiolite Complex. [ABSTRACT FROM AUTHOR]

In the northwestern part of Northern Apennines, between Curone and Staffora Valleys, the tectonic superposition between the External Ligurian Units (i.e. the ophiolitic-bearing chaotic complex of the Groppallo Unit and the non-ophiolitic Cassio Unit), the Middle Eocene – Miocene wedge-top basin Epiligurian Units succession, and the Late Messinian – Pliocene Po Plain succession, records the multistage tectono-stratigraphic evolution from subduction to continental collision. Our geological map, at the 1:20,000 scale, allows us to define 6 main tectonic stages on the basis of (i) the crosscutting relationships between main faults and local to regional stratigraphic unconformities and (ii) the differentiation among different types of chaotic rock unit (olistostromes and broken formations) deposited since Late Cretaceous to late Messinian. This approach provides a new understanding on the tectono-stratigraphic evolution of this sector, and its meaning in the evolution of the northwestern part of Northern Apennines. [ABSTRACT FROM PUBLISHER]

The External Ligurian and Epiligurian Units in the Northern Apennines of Italy are tectonically juxtaposed with the Tertiary Piedmont Basin along the Villalvernia – Varzi Line, which represents a regional scale fault zone, E-striking. Our map, at the 1:20,000 scale, describes the tectono-stratigraphic evolution of this sector that resulted from multistage faulting along that fault zone. Four main tectonic stages are defined on the basis of the crosscutting relationships between mapped faults and stratigraphic unconformities: late Priabonian – Rupelian, Chattian – early Miocene, late Serravallian – Tortonian, and late Messinian – early Pliocene. Our results demonstrate that since the late Burdigalian, the Villalvernia – Varzi Line was sealed by the gravitational emplacement of a chaotic rock body. The deposition of the late Serravallian – early Messinian succession is controlled by NW-striking strike-slip faults that crosscut to the west the Villalvernia – Varzi Line. Extensional tectonics related to regional scale N-dipping tilting characterized the late Messinian – early Pliocene time interval. [ABSTRACT FROM PUBLISHER]

The Apenninic fold-and-thrust belt in Italy represents one of several interconnected circum-Mediterranean orogens developed after the Late Cretaceous – early Cenozoic closure of Tethys and convergence between the European and African plates. The Geological Map of the Aventino River Valley, at 1:25,000 scale, provides original mapping of the outermost sector of Central Apennines in the Abruzzi region. Focusing on detailed mapping of the crosscutting relationships between the main regional thrust faults and tectonically driven stratigraphic unconformities, the map describes the complex structural and stratigraphic relationships between the Outer Abruzzi units (i.e. Porrara Unit), Apulia – Adriatic deformed units (i.e. Majella and Casoli Units), and the allochthonous Molise and Sicilide units. These tectono-stratigraphic relationships result from four main tectonic stages that occurred sequentially over a short time interval from late Messinian to early Pliocene. [ABSTRACT FROM AUTHOR]

The External Ligurian Units in western Monferrato (NW-Italy) have been always described as an undifferentiated chaotic complex. This map, at 1:10,000 scale, describes in detail the tectono-stratigraphic setting of these Units in the sector of the Alps–Apennines junction. Here, the External Ligurian Units represent the northwestern prolongation of the Northern Apennines and consist of a Late Cretaceous chaotic succession represented by theArgille varicoloriand the overlaying Monte Cassio Flysch. The late Eocene–Miocene episutural succession of the Tertiary Piedmont Basin rests unconformably on the External Ligurian Units. The mapped crosscutting relationships between stratigraphic unconformities and faults allow us to describe a complex tectono-stratigraphic setting that is the product of four tectonic stages. Layer-parallel extension related to Late Cretaceous–early Eocene deformation occurred in the internal sector of the Alpine accretionary wedge and is preserved within the External Ligurian Units which is sealed by the late Eocene deposits of the Tertiary Piedmont Basin. The unconformity at the base of the Oligocene succession records the drowning of shelf sediments controlled by NW-striking left-lateral transtensive faulting. A WNW-striking and NE-verging thrust superposes the External Ligurian Units onto the late Eocene–Oligocene deposits and it is sealed by the gravitational emplacement of late Oligocene Polygenetic argillaceous breccias. Both the WNW-striking thrust and the Polygenetic argillaceous breccias are cut by NW-striking right-lateral transpressive faults that are, in turn, sealed by the Tortonian unconformity. [ABSTRACT FROM AUTHOR]