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In this work we present new AMS and structural results from the Ferdows active fold-thrust system (Lut block, Central Iran). AMS analyses show that the Miocene units of the Upper Red Formation have a well defined magnetic fabric of tectonic origin, with both magnetic lineation and magnetic foliation oriented parallel to the regional fold axes. In most of the cases the magnetic fabric, acquired when the bedding was still horizontal, is related to different degrees of LPS shortening. In some other cases, the magnetic foliation is vertical and oblique to the bedding, suggesting that in the Ferdows thrust-fold structure a cleavage system, not visible at the outcrop scale, has been developed as a consequence of later shortening related to the activity of the thrust system, responsible of the recent earthquakes in the area. Results from this study establish a relationships between the recent tectonics of the area and the evolution of the magnetic fabric and demonstrate that a well defined magnetic fabric of pure tectonic origin can also develop in poorly deformed rocks lacking field evidence of pervasive internal deformation. (C) 2015 Elsevier Ltd. All rights reserved.

According to previous paleomagnetic analyses, the northward latitudinal drift of Iran related to the closure of the Paleo-Tethys Ocean resulted in the Late Triassic collision of Iran with the Eurasian plate and Cimmerian orogeny. The post-Cimmerian paleogeographic and tectonic evolution of Iran is instead less well known. Here we present new paleomagnetic data from the Upper Jurassic Bidou Formation of Central Iran, which we used in conjunction with published paleomagnetic data to reconstruct the history of paleomagnetic rotations and latitudinal drift of Iran during the Mesozoic and Cenozoic. Paleomagnetic inclination values indicate that, during the Late Jurassic, the Central-East-Iranian Microcontinent (CEIM), consisting of the Yazd, Tabas, and Lut continental blocks, was located at low latitudes close to the Eurasian margin, in agreement with the position expected from apparent polar wander paths (APWP) incorporating the so-called Jurassic massive polar shift, a major event of plate motion occurring in the Late Jurassic from 160 Ma to 145–140 Ma. At these times, the CEIM was oriented WSW–ENE, with the Lut Block bordered to the south by the Neo-Tethys Ocean and to the southeast by the Neo-Sistan oceanic seaway. Subsequently, the CEIM underwent significant counter-clockwise (CCW) rotation during the Early Cretaceous. This rotation may have resulted from the northward propagation of the Sistan rifting- spreading axis during Late Jurassic–Early Cretaceous, or to the subsequent (late Early Cretaceous?) eastward subduction and closure of the Sistan oceanic seaway underneath the continental margin of the Afghan Block. No rotations of, or within, the CEIM occurred during the Late Cretaceous–Oligocene, whereas a second phase of CCW rotation occurred after the Middle-Late Miocene. Both the Late Jurassic–Early Cretaceous and post Miocene CCW rotations are confined to the CEIM and do not seem to extend to other tectonic regions of Iran. Finally, an oroclinal bending mechanism is proposed for the origin of the curved Alborz Mountains, which acquired most of its curvature in the last 8 Myr.

The study of two sedimentary records sampled in the fluvio-lacustrine succession of high Salto river valley (Rieti, central Italy) was originated in the frame of the Geomorphologic Map of Italy ( APAT, 2008 ) field survey and improved with a multidisciplinary approach addressed to a better knowledge of the Plio-Pleistocene continental environments of central Apennines. The two successions are associated to different sedimentary facies, with lateral heteropic relations: the deposits cropping out at Marano de' Marsi are thought to represent deposition in the distal portion of a lacustrine delta, while those of Borgorose took place in a frankly lacustrine environment. The sediment succession from Marano de' Marsi (11 m) was sampled from an outcrop, the one from Borgorose (24.5 m) from a drillhole. Palaeomagnetic investigations carried out on both sediment records indicate a normal magnetic polarity and very low magnetic susceptibility values. In the record from Marano de' Marsi section, gymnosperm pollen is prevailing. Four main and short angiosperm arboreal pollen oscillations can however be observed, the oldest of which more marked. The gymnosperms are mainly represented by Pinus haploxylon type, Pinus sylvestris type, Cedrus , Picea , Abies , Cathaya , Tsuga , Taxodium type. Among angiosperms the dominant taxa , some of which at present extinct in Italy, are Quercus , Zelkova , Ulmus , Carya and Pterocarya . The presence of pollen of subtropical taxa as Nyssa , cfr. Rhoiptelea , Liquidambar , Engelhardia is worth to be mentioned. The investigation was integrated also by a preliminary study of macrofossils. Fossil impressions with some organic matter of angiosperm and gymnosperm leaves and seeds/fruits were ascribed to Acer cfr. monspessulanum , Carpinus cfr. orientalis , Engelhardia , Fagus , Hedera , Liquidambar , Quercus , Rosa , Abies and Pinus . The 24.5 m long sediment core from Borgorose resulted very poor in pollen, with the same list of arboreal taxa, at present extinct in Italy, found at Marano de' Marsi, and a diagram was drawn only for the stretch of the core between 3 and 8.2 m. Gymnosperms ( P. haploxylon type is dominant, and accompanied by P. sylvestris type, Picea , Taxodium type, Cedrus , and Tsuga ) are always prevailing. The results obtained by this interdisciplinary investigation indicate that Marano de' Marsi and Borgorose successions can be possibly attributed to the Upper Pliocene (normal polarity Olduvai subchron) even if an older age, considering the present state of the art on Pliocene continental records, and the peculiarity of the site and of the region, cannot be excluded.

The present-day arcuate shape of the Calabrian Arc has been accomplished during Neogene and Early Pleistocene by large and opposite vertical axis rotations along the two arms of the Arc. Clockwise (CW) rotations have been systematically registered in Sicily and Calabria, whereas counterclockwise (CCW) rotations were measured in Southern Apennines. Such opposite vertical axis rotations ceased in the uppermost part of the Lower Pleistocene (about 1 Ma ago) along almost the entire Calabrian Arc and are not observed in the present-day GPS velocity field. The end of the Calabrian Arc bending during the Quaternary marks a decrease in the efficiency of the tectonic processes related to the long-lived subduction of the Ionian slab, which caused the halting of the back-arc opening in the Southern Tyrrhenian Sea.

9 figures, 1 table., New paleomagnetic results from Neogene sedimentary sequences from the Betic chain (Spain) are here presented. Sedimentary basins located in different areas were selected in order to obtain paleomagnetic data from structural domains that experienced different tectonic evolution during the Neogene. Whereas no rotations have been evidenced in the Late Tortonian sediments in the Guadalquivir foreland basin, clockwise vertical axis rotations have been measured in sedimentary basins located in the central part of the Betics: the Aquitanian to Messinian sediments in the Alcalà la Real basin and the Tortonian and Messinian sediments in the Granada basin. Moreover, counterclockwise vertical axis rotations, associated to left lateral strike-slip faults have been locally measured from sedimetary basins in the eastern Betics: the Middle Miocene to Lower Pliocene sites from the Lorca and Vera basins and, locally, the Tortonian units of the Huercal-Overa basin. Our results show that, conversely from what was believed up to now, paleomagnetic rotations continued in the Betics after Late Miocene, enhancing the role of vertical axis rotations in the recent tectonic evolution of the Gibraltar Arc., Financial support for this work was provided by Projects: a) 01-LECEMA22F [WESTMED] by the European Science Foundation under the EUROCORES Programme EUROMARGINS, through contract No. ERAS-CT-2003-980409 of the European Commission, DG Research, FP6 (M.M., F.C., M.P. and C.F.); b) BTE2003-05057-C02 (A.C–B) and c) REN2001-3868-C03-01 (M.C.) from the MEC and FEDER founding (Spain). We thank G. Booth-Rea for his help in taking samples in the eastern Betics. M.M. and C.F. are particularly grateful to Victor Garcia Duenas who introduce them to the geology of the Betics.

An integrated structural, anisotropy of magnetic susceptibility (AMS) and paleomagnetic study was carried out on Plio-Pleistocene sedimentary basins in eastern Sicily. These basins belong to three main tectonic domains: the Tyrrhenian hinterland domain, the Catania foredeep domain, and the Hyblean foreland domain. We sampled 329 oriented samples from 25 sites in selected areas from the different tectonic domains. The AMS is typical for weakly deformed sediments, with a magnetic foliation sub-parallel to the bedding plane, and a well-defined magnetic lineation. The orientation of the magnetic lineation is strongly controlled by the main tectonic deformation recorded in the basins. Structural and AMS data define a transition from NW–SE extension in the Tyrrhenian hinterland domain, to E–W compression in the Catania foredeep domain, to E–W extension in the Hyblean foreland domain, respectively. Reliable paleomagnetic results have been obtained in 12 out of 25 sampled sites. Data show that no significant rotations occurred in any of the studied basins at least since the middle Pleistocene. These results allow us to define an upper limit to the large rotations about vertical axes that have been previously found in the Calabria and Sicily regions.

We present the results of anisotropy of magnetic susceptibility (AMS) analysis carried out in weakly deformed, Upper Cretaceous marine marls from the Southern Pyrenees. The data refer to 23 sites distributed in the fine-grained intervals of the Vallcarga and Barbaruens formations, extending along the hangingwall and footwall of the Cotiella-Boixols thrust. The observed magnetic fabrics are typical of early stages of deformation, and show oblate, triaxial and prolate magnetic ellipsoids. In most of the sites, a magnetic foliation parallel to bedding can be observed. A well-defined magnetic lineation, which is correlated with the main tectonic features of the studied region, can be recognised. We interpret the observed magnetic fabric as related to a tectonic overprint on an original, compaction, sedimentary fabric. The tectonic AMS fabric is related to the superimposition of two sequential, and non-coaxial fold-and-thrust events: N–S to NNW–SSE folding, related to oblique ramps of Late Cretaceous thrusts, and WNW–ESE folding, related to the main, Eocene Pyrenean thrusting stage.

Results are presented of structural analysis and anisotropy of magnetic susceptibility (AMS) analysis of Plio-Pleistocene clayey units from the extensional Tyrrhenian margin of central Italy. Data have been collected in different tectonic settings, mainly strike-slip and transverse extensional structures. At the sites with major evidence of Plio-Pleistocene tectonics, there appears a close relationship between magnetic lineations and stretching directions. Stretching processes that were able to modify the original magnetic fabric pre-dated significant normal-fault-related tilting, and therefore were active at the very first stage of extensional deformation. The relationships between AMS and structural trends in an extensional regime seem distinctively different from those reported in compressional regimes. This kind of analysis may be useful in the geodynamic interpretation of ambiguous structures.