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The continental redbeds from the Internal Domains of the central-western Mediterranean Chains have an important role in the palaeogeographic and palaeotectonic reconstructions of the Alpine circum-Mediterranean orogen evolution since these redbeds mark the Triassic-Jurassic rift-valley stage of Tethyan rifting. The composition and the sedimentary evolution of the Middle Triassic to Lowermost Jurassic continental redbeds of the San Marco d'Alunzio Unit (Peloritani Mountains, Southern Italy), based on mineralogical and chemical analyses, suggests that the studied mudrock sediments share common features with continental redbeds that constitute the Internal Domains of the Alpine Mediterranean Chains. Phyllosilicates are the main components in the mudrocks. The 10 Å-minerals (illite and micas), the I-S mixed layers, and kaolinite are the most abundant phyllosilicates. The amount of illitic layers in I-S mixed layers coupled with the illite crystallinity values (IC) are typical of high degree of diagenesis, corresponding to a lithostatic/tectonic loading of about 4-5 km. The mineralogical assemblage coupled with the A-CN-K plot suggest post-depositional K-enrichments. Palaeoweathering proxies (PIA and CIW) record intense weathering at the source area. Further, the studied sediments are affected by reworking and recycling processes and, as consequence, it is likely these proxies monitor cumulative effect of weathering. The climate in the early Jurassic favoured recycling and weathering occurred under hot, episodically humid climate with a prolonged dry season. The source-area is the low-grade Paleozoic metasedimentary basement. Mafic supply is minor but not negligible as suggested by provenance proxies. [ABSTRACT FROM AUTHOR]

Abstract: This work discusses the synsedimentary structural control affecting the turbidites of the Marnoso-arenacea Formation (MAF) deposited in an elongate, NW-stretched foredeep basin formed in front of the growing Northern Apennines orogenic wedge. The stratigraphic succession of the MAF (about 4000 m thick) records the progressive closure of the Apennine foredeep basin due to the NE propagation of thrust fronts. In this setting, Langhian to Serravallian turbidites are overlain by Tortonian mixed turbidite deposits, i.e. sandstone-rich low-efficiency turbidites. The high-resolution stratigraphic framework of basin-plain turbidites has made it possible to identify five informal stratigraphic units (I, II, III, IV, V) mainly on the basis of the structural control highlighted by: 1) the presence of topographic highs and relative depocentres detected through a progressive flattening approach, and 2) the presence of thrust-related mass-transport complexes and the progressive appearance and disappearance of five bed types (Types 1, 2, 3, 4, 5) considered important to understand the interaction between flow efficiency and basin morphology. By contrast, the upper part of the MAF succession (Tortonian in age) is formed by more sandstone-rich systems characterized by beds whose origin is likely to depend, at least in part, upon flow decelerations related to topographic confinement due to the progressive closure of the foredeep. The vertical and lateral distribution of these types of beds is, therefore, useful for the reconstruction of the morphological evolution of structurally controlled basins; in the MAF example, this is mainly due to the progressive narrowing of the foredeep caused by the propagation of the main thrust fronts toward the foreland. [Copyright &y& Elsevier]

Abstract: Mainly on the basis of seismic data, we reconstruct magnitude and timing of Miocene to Present vertical movements in the region of the Savigliano basin, an up to 4 km thick succession of Neogene to Quaternary sediments accumulated inside the Alpine arc at the western termination of the Po Plain. We focus, in particular, on the margins of the basin which are the link between the mountain range and the subsiding basin. Seismic data from these regions allow for the definition of upward and downward vertical movements (uplift-exhumation and subsidence) with a spatial and temporal resolution which cannot be attained by other methods. The eastern, southern and western margins of the Savigliano basin display very different geometries of the sedimentary bodies and, therefore, document different vertical movements during Miocene to Present times. The eastern part of the Savigliano basin, and the regions to the E, experienced subsidence followed by exhumation. The southern margin of the basin, in the Cuneo area, was much more stable with Miocene to present formations all pinching-out close to the present day outcropping position of the basement-sedimentary cover contact. In the W, seismic sections record a stage of tilting until the Burdigalian, followed by generalized subsidence which affected also the adjacent regions of the SW Alps. The overall pattern of vertical movements is essentially controlled by the NW-ward migration of a syncline–anticline couple with the synclinal axis presently located in the center of the Savigliano basin. The width of the folds is in the order of 30–60 km (1/2 wavelength). In map view, the trace of the fold axes changes from N–S in the Savigliano basin to E–W in the Alessandria basin. [Copyright &y& Elsevier]

Ten samples from a Late Messinian section measured at Capo Rossello, a few hundred metres laterally from and stratigraphically, immediately below the Miocene Pliocene boundary stratotype, have been invesitigated by various techniques: carbonate content, grain-size analysis, loss on ignition, clay mineral composition, frequency of euryhaline ostracods, Two lithological sub-units, with different palaeoenvironmental implications, are recognized. Both sub-units were deposited after the termination of evaporitic conditions, and immediately after deposition of an ash fall tuff. The lower unit is the Congeria marl which yields the lago-mare' faunal assemblage, the autochthony of which is supported by biometrical analysis of Cyprides agrigentina, indicating brackish, shallow-water conditions with Paratethyan affinities, and the upper, the Arenazzolo, a thin sandy unit indicating a higher' energy environment whose duration is estimated at some thousand years. Marine faunas yielded by the Arenazzolo are interpreted as allochthonous, Sedimentary slructures suggest a littoral setting at the edge of the lake, or a delta lobe. The main environmental change occurs at the base of the immediately overlying Trubi Formation. where open marine condilions indicative of oceanic depths mark the termination of the Messinian salinity crisis. [ABSTRACT FROM AUTHOR]