ABSTRACT The geometry of collisional mountain belts, which were formed at the expense of passive continental margins, is often complex because orogenic structures, such as thrusts and related folds, commonly interfere with pre-orogenic extensional structures, namely, normal faults, resulting in kinematically complex, composite structural assemblages. In these settings, analysis of the relationships between depositional and structural features may provide very useful tools to correctly unravel the local sedimentary and deformational history and relative ages of structures. Analysis of the relationships between minor normal faults and slumps near Frontale in the Umbria-Marche Apennines of Italy made it possible to correctly unravel the local chronology of events and hence to infer the depositional and deformation history of a part of the Upper Cretaceous–Paleogene Scaglia Rossa Formation pelagic basin. The results of this investigation made it possible to ascribe the normal faults to events that predate the construction of the Umbria-Marche mountain belt. Therefore, the normal faults at Frontale are distinct from those that overprint the main compressional structures responsible for the present-day seismicity of central Italy.

ABSTRACT The Popigai (100 km in diameter) and the Chesapeake Bay (40–85 km diameter) impact structures formed within ~10–20 k.y. in the late Eocene during a 2 m.y. period with enhanced flux of 3 He-rich interplanetary dust to Earth. Ejecta from the Siberian Popigai impact structure have been found in late Eocene marine sediments at numerous deep-sea drilling sites around the globe and also in a few marine sections outcropped on land, like the Massignano section near Ancona in Italy. In the Massignano section, the Popigai layer is associated with an iridium anomaly, shocked quartz, and abundant clinopyroxene-bearing (cpx) spherules, altered to smectite and flattened to “pancake spherules.” The ejecta are also associated with a significant enrichment of H-chondritic chromite grains (>63 μm), likely representing unmelted fragments of the impactor. The Massignano section also contains abundant terrestrial chrome-spinel grains, making reconstructions of the micrometeorite flux very difficult. We therefore searched for an alternative section that would be more useful for these types of studies. Here, we report the discovery of such a section, and also the first discovery of the Popigai ejecta in another locality in Italy, the Monte Vaccaro section, 90 km west of Ancona. The Monte Vaccaro section biostratigraphy was established based on calcareous nannoplankton, which allowed the identification of a sequence of distinct bioevents showing a good correlation with the Massignano section. In both the Monte Vaccaro and Massignano sections, the Popigai ejecta layer occurs in calcareous nannofossil zone CNE 19. The ejecta layer in the Monte Vaccaro section contains shocked quartz, abundant pancake spherules, and an iridium anomaly of 700 ppt, which is three times higher than the peak Ir measured in the ejecta layer at Massignano. In a 105-kg-size sample from just above the ejecta layer at Monte Vaccaro, we also found an enrichment of H-chondritic chromite grains. Because of its condensed nature and low content of terrestrial spinel grains, the Monte Vaccaro section holds great potential for reconstructions of the micrometeorite flux to Earth during the late Eocene using spinels.

ABSTRACT The complete and well-studied pelagic carbonate successions from the Umbria-Marche basin (Italy) permit the study of the event-rich stratigraphic interval around the Cretaceous-Paleogene boundary (e.g., Deccan volcanism, boundary impact, Paleocene recovery, and climate). To test the robustness of various proxy records (bulk carbonate δ 13 C, δ 18 O, 87 Sr/ 86 Sr, and Ca, Fe, Sr, and Mn concentrations) inside the Umbria-Marche basin, several stratigraphically equivalent sections were investigated (Bottaccione Gorge, Contessa Highway, Fornaci East quarry, Frontale, Morello, and Petriccio core). Besides the classical Gubbio sections of Bottaccione and Contessa, the new Morello section is put forward as an alternative location for this stratigraphic interval because it is less altered by burial diagenesis. Elemental profiles (Ca, Fe, Sr, Mn) acquired by handheld X-ray fluorescence (pXRF) efficiently provide regional chemostratigraphic and paleoenvironmental information. The Deccan volcanism, the Cretaceous-Paleogene boundary, the characteristic pattern of the Sr/Ca profile across the boundary driven by the extinction and recovery of coccolithophores, and the Dan-C2 hyperthermal event are examples of such recorded paleoenvironmental events. Moreover, cyclostratigraphic analyses of proxies of detrital input (magnetic susceptibility and Fe concentrations) show the imprint in the sedimentary record of a 2.4 m.y. eccentricity minimum around 66.45–66.25 Ma, and suggest that the occurrence of the Dan-C2 hyperthermal event was astronomically paced.

ABSTRACT We reconstructed a record of the micrometeorite flux in the Late Cretaceous using the distribution of extraterrestrial spinel grains across an ~2 m.y. interval of elevated 3 He in the Turonian Stage (ca. 92–90 Ma). From ~30 m of the limestone succession in the Bottaccione section, Italy, a total of 979 kg of rock from levels below and within the 3 He excursion yielded 603 spinel grains (32–355 μm size). Of those, 115 represent equilibrated ordinary chondritic chromite (EC). Within the 3 He excursion, there is no change in the number of EC grains per kilogram of sediment, but H-chondritic grains dominate over L and LL grains (70%, 27%, and 3%), contrary to the interval before the excursion, where the relation between the three groups (50%, 44%, and 6%) is similar to today and to the Early Cretaceous. Intriguingly, within the 3 He anomaly, there is also a factor-of-five increase of vanadium-rich chrome spinels likely originating from achondritic and unequilibrated ordinary chondritic meteorites. The 3 He anomaly has an unusually spiky and temporal progression not readily explained by present models for delivery of extraterrestrial dust to Earth. Previous suggestions of a relation to a comet or asteroid shower possibly associated with dust-producing lunar impacts are not supported by our data. Instead, the spinel data preliminary indicate a more general disturbance of the asteroid belt, where different parent bodies or source regions of micrometeorites were affected at the same time. More spinel grains need to be recovered and more oxygen isotopic analyses of grains are required to resolve the origin of the 3 He anomaly.

ABSTRACT The present-day ocean-climate system configuration took shape during the Miocene Epoch. Toward the end of the epoch, in the late Tortonian at ca. 8.5 Ma, there was an exceptional event: collisional disruption of an >150-km-diameter asteroid, which created the Veritas family of asteroids in the asteroid belt. This event increased the flux of interplanetary dust particles rich in 3 He to Earth and probably caused a period of increased dust in the atmosphere, with consequent alteration of global and local environmental conditions. A late Miocene 3 He anomaly likely related to the Veritas event has been registered in deep-sea sediments from Ocean Drilling Program (ODP) Site 926 (Atlantic Ocean), ODP Site 757 (Indian Ocean), and in the late Tortonian–early Messinian Monte dei Corvi section near Ancona, Italy. Here, we report the results of a study in the Monte dei Corvi section aimed to recover extraterrestrial chrome-spinel grains across the 3 He anomaly interval, as has been done for the similar late Eocene 3 He anomaly in the nearby Massignano section. In this study, three ~100 kg samples were collected from the Monte dei Corvi section: two within the 3 He peak interval and one outside the anomaly interval as a background reference sample. In total, 1151 chrome-spinel grains (>63 µm) were recovered, but based on chemical composition, none of the grains has a clear extraterrestrial origin. This supports the inference that the 3 He anomaly is indeed related to the Veritas event and not to an approximately coeval breakup of a smaller H-chondritic body in the asteroid belt, an event registered in meteoritic cosmic-ray exposure ages. Spectral studies of the Veritas asteroids indicate that they are made up of carbonaceous chondritic material. Such meteorites generally have very low chrome-spinel concentrations in the grain-size range considered here, contrary to the very chromite-rich ordinary chondrites. The terrestrial grains recovered were classified, and their composition showed that all the grains have an ophiolitic origin with no substantial compositional and distributional change through the section. The source area of the terrestrial grains was probably the Dinarides orogen.

ABSTRACT An ~10-m-thick sequence of Quaternary eolian sands from the island of Vis (Croatia) was investigated with the aim to unravel and understand their origin, characteristics, and age. The sand deposit is situated in a karstic depression in the eastern part of the island at an altitude of ~100 m above sea level (a.s.l.), and it is composed of a subhorizontally laminated unit at the bottom underlying a cross-bedded unit. The sand is very well sorted and fine grained and composed predominantly of carbonate lithic fragments, which most likely originated from the Dinaric karst region. The siliciclastic component of these sands reflects a more complex lithological source, including older sedimentary (e.g., flysch successions in the area, as well as older Quaternary deposits), magmatic, and metamorphic rocks probably originating from the Inner Dinarides, which were eroded and comminuted by glacial and periglacial activity during the last glacial period, and transported toward the Adriatic foreland by major rivers such as the Cetina and Neretva. Grain size and shape characteristics of the sands as well as their sedimentary structure indicate their eolian origin. Optically stimulated luminescence (OSL) dating was applied to determine the depositional age of the sediment. The obtained ages can be correlated to the Last Glacial Maximum (oxygen isotope stage [OIS] 2), implying that during the peak of that glaciation, the central Adriatic basin was dry land, a vast plain exposed to eolian deflation.

ABSTRACT In this paper, we present a case study to demonstrate the potential of photogrammetry in cyclostratigraphic applications. To this end, we considered an ~300-m-thick section exposing the Lower Jurassic Calcare Massiccio Formation in the Marche Apennines of central Italy. The Calcare Massiccio comprises a thick succession of peritidal shallow-water carbonates displaying a prominent sedimentary cyclicity, where supratidal and subtidal facies alternate. The section investigated in this study is exposed on the wall of an active quarry and is almost completely inaccessible because it is vertical and because of safety and liability regulations. This setting prevents the application of standard sampling and facies analysis techniques on the whole series. An accurate three-dimensional model of the quarry wall was therefore produced by processing ~360 digital images through photogrammetry and generating a high-resolution (centimeter-scale) point cloud of the outcrop with red-green-blue (RGB) values associated with each point. An ~150-m-long log representing color variations on a continuous portion of the exposed succession was then extracted from the point cloud by converting the original RGB values to grayscale values. The main facies were directly investigated in an ~10-m-long accessible section that was logged and sampled, and it was established that supratidal facies with planar stromatolites and teepee structures are darker in color, while subtidal facies, made of bioturbated mudstones to floatstones with gastropods and oncoids, display lighter color. This provided ground-truth data with which to interpret the grayscale variations in terms of facies alternations. Time-series analysis was then carried out on the grayscale series, and this revealed prominent cyclicities. Because the biochronostratigraphic framework of the Calcare Massiccio is poor, the potential orbital origin of these frequencies was tested with the average spectral misfit technique. Preliminary results suggest that the observed spectral features are compatible with Milankovitch periods and that astronomical forcing might have been a major driver in the deposition of the Calcare Massiccio Formation. Furthermore, they testify to the great potential of photogrammetry in cyclostratigraphic applications, especially when large-scale, inaccessible outcrops have to be investigated.

ABSTRACT The late Eocene was marked by multiple impact events, possibly related to a comet or asteroid shower. Marine sediments worldwide contain evidence for at least two closely spaced impactoclastic layers. The upper layer might be correlated with the North American tektite-strewn field (with the 85-km-diameter Chesapeake Bay impact structure [USA] as its source crater), although this is debated, whereas the lower, microkrystite layer (with clinopyroxene [cpx]-bearing spherules) was most likely derived from the 100-km-diameter Popigai impact crater (Russia). The Eocene-Oligocene global stratotype section and point is located at Massignano, Italy, and below the boundary, in the late Eocene, at the 5.61 m level, shocked quartz and pancake-shaped smectite spherules that contain (Ni- and Cr-rich) magnesioferrite spinel crystals are found. These are associated with a positive Ir anomaly in deposits with the same age as the Popigai-derived cpx spherule layer. This layer is overlain by another Ir-rich layer, likely due to another large impact event. From a large amount of “pancake-bearing” rock, we isolated a few hundred milligrams of this spinel-rich material. The tungsten isotopic composition of this material shows more or less a terrestrial composition. However, the spinel-rich materials have excess 54 Cr values (expressed as ε 54 Cr, which is the per ten thousand deviation of the 54 Cr/ 52 Cr ratio from a terrestrial standard) of around –0.4 to –0.5 ε 54 Cr, which distinctly point to an ordinary chondritic impactor. This result supports the asteroid impact interpretation but not the comet impact hypothesis.

ABSTRACT The earliest Pleistocene fossil forest of Dunarobba (Umbria, Italy) consists of a set of more than 70 tree trunks of an extinct species of sequoia or cypress with original cellulose still preserved. Spectral analyses of tree-ring series (325 and 448 yr in duration) combined with oxygen isotope analyses of the cellulose provide a glimpse into the mean annual temperature and the interannual climate variability that characterized this region at the beginning of the Pleistocene, when the concentration of atmospheric CO 2 was ~400 ppm. The high-frequency variability of the ring width time series shows significant spectral components that are consistent with the influence from the North Atlantic Oscillation, and to a lesser extent, solar cycles and El Niño–Southern Oscillation. The mean annual temperature estimate of ~19 °C, based on a model that combines ring widths and oxygen isotope values, is a full 6 °C warmer than the present-day value for this region. These elevated temperatures are consistent with estimates from pollen analyses and with estimates from higher latitudes.

ABSTRACT In this study, we discuss the results from different luminescence dating methods applied to four samples of Pleistocene slack-water sediments from the Frasassi hypogenic cave system, in the northeastern Apennines of Italy. Two samples came from a well-sorted, fine sand deposit in the Grotta Grande del Vento cave (SDS site), while two others were taken from a borehole through a clayey deposit in the adjacent Caverna del Carbone cave (CDC site). Both sites are located at an elevation of ~235 m above sea level (asl), which corresponds to ~30 m above the thalweg of the Sentino River flowing through the Frasassi Gorge outside the cave. In the Frasassi multistory cave system, the elevation of 235 ± 5 m asl corresponds to the third karst level or “floor,” the minimum age of which from speleothem U-Th dating is ca. 130 ± 15 ka. The luminescence ages for the two samples from the SDS site are in good agreement with each other within error, just like the two samples from the CDC profile. Different luminescence dating protocols were used to determine the ages for each individual sample. By applying this comparative approach, and taking the luminescence characteristics of the samples into consideration (quartz optically stimulated luminescence, different feldspar luminescence signals), the ages could be based on the most robust measurement protocol. The ages presented here were all derived from measurements using the post-infrared infrared signal of potassium-rich feldspar stimulated at a temperature of 225 °C (pIRIR225). Incomplete bleaching of the luminescence signal prior to deposition, leading to age overestimation when not detected and corrected for, was not a significant factor for the samples under investigation, because ages calculated for luminescence signals with different bleachability yielded results in agreement within error. Bleaching can therefore be assumed to have been sufficient before the samples entered the cave system. The ages determined for both sites are reliable from a methodological standpoint. The pIRIR225 luminescence dates from the SDS sand range between 129 and 101 ka and are consistent with the minimum age for the third cave floor (~235 m asl) as obtained from previous U-Th dating. In contrast, the pIRIR225 luminescence dates obtained from the clay-rich CDC deposit range from 217 to 158 ka, which is consistent with the minimum age for the fifth subhorizontal cave level when measured from the modern water table, found at ~65 m above the present river thalweg. This apparent discrepancy may be due to the fact that the present entrance of the CDC cave was incised by the river on the south side of Frasassi Gorge sometime during the Eemian interglacial period (marine isotope stage [MIS] 5e), but, being part of a hypogenic karst system in an uplifting tectonic structure, the actual third floor was preexisting, thus anteceding the river incision. On the other hand, the fifth floor of the cave system, some 30 m above the third floor, was incised sometime during the interglacial MIS 7 at around 200 ka, at a time when the saturated phreatic third floor had already been formed and thus was capable of collecting the fine suspension sediment settling from muddy river water flooding the cave.

ABSTRACT In this study, we present a composite δ 18 O and δ 13 C record obtained from four speleothems from the Grotta Grande del Vento Cave, located within the Frasassi karst system, northeastern Apennines of central Italy. The ages were determined by U-series analysis, employing thermal ionization mass spectrometry (TIMS), and the composite isotopic profile covers most of the time period from ca. 95,000 yr B.P. until ca. 10,000 yr B.P., including the last part of marine isotope stage (MIS) 5, most of the last glacial (MIS 4–2), and the earliest Holocene (MIS 1), with a hiatus lasting from ca. 65,000 to ca. 55,000 yr B.P. We compared this record with other speleothem records from the Eastern Mediterranean, with caves from western Portugal, with two marine records from the Eastern Mediterranean and the Aegean Sea, and with the North Greenland Ice Core Project (NGRIP) ice-core record. The Frasassi speleothem record provides further insight for a wider regional understanding of the paleoclimate record through the discrepancies and similarities between the northeastern Apennines of central Italy and the Western, Eastern, and northeastern Mediterranean regions. The time interval between ca. 86,000 and 83,000 yr B.P. shows low δ 18 O values in the Western and Eastern Mediterranean speleothems and the marine records. This period coincides with sapropel (S3) and is associated with increased hydrological activity and warming. On the other hand, Frasassi speleothem δ 18 O data do not show a similar low trend, suggesting that increased hydrological activity either did not reach the Frasassi region and/or the region received rainfall from other sources and/or the proportion of winter-summer rainfall was different. Another interval in which different conditions prevailed in the Frasassi region is during the transition from MIS 5 to glacial MIS 4, from ca. 83,000 to 65,000 yr B.P., when Frasassi speleothem δ 18 O values decreased, whereas all other records show a clear increase in δ 18 O. Comparison with the NGRIP record suggests that Northern Hemisphere temperature changes are reflected in Frasassi speleothem δ 18 O fluctuations during this interval. A major pronounced isotopic event associated with warming and pluvial conditions during the last glacial evident in the entire Mediterranean region between ca. 54,500 and 52,500 yr B.P. is recorded also in the Frasassi speleothem isotopic profile. This event is followed by a transition from wet and warm climatic conditions to cold conditions. The end of the last glacial is associated with climate instability, evident mainly from the very large oscillations in the Frasassi δ 13 C record. The transition from the last glacial to early Holocene is characterized by a decreasing trend in δ 18 O and a sharp increase in δ 13 C values.

ABSTRACT The massive Jurassic limestone making up the core of the Frasassi-Valmontagnana blind thrust anticline hosts a large sulfidic cave complex, which, due to Pleistocene tectonic uplift, has been incised by the Sentino River, forming the deep Frasassi Gorge. The Frasassi cave complex is organized into seven horizontal levels, with the youngest and presently active one at river level, and the oldest (ca. 1.2 Ma) one some 200 m above the Sentino River. Therefore, the Frasassi cave complex records the river incision history of this still-active Apennine mountain belt. In addition to an uplift rate of ~0.55 mm/yr for the Holocene, previous radioisotopic dating and surveying of phreatic calcite deposits revealed an overall tilting of the Frasassi anticline of ~0.2° toward N60E for the past 9000 or so years. Our study adds to this history of tectonic tilting by focusing on a group of 30 tilted stalagmites found at the bottom of the Abisso Ancona of the Grotta Grande del Vento (the largest room in the Frasassi complex). These stalagmites have a fairly uniform plunge of ~81° trending toward N30W, and we interpret this to record a tilt of the cave toward S30E during the formation of the stalagmites. From U-Th dating of these paleotiltmeters, we deduce that the Frasassi anticline was tilted by ~0.3° from 32 to 7 k.y. B.P., and the tilt rate gradually increased during this period. The 60° (NE) direction of oblique-slip faults in this area and the local focal mechanisms of recent seismic activity suggest that the tilting is caused by movement along a listric oblique strike-slip zone south of the Frasassi anticline. Our findings also demonstrate that given the right conditions, stalagmites can be used as paleotiltmeters that provide insight into recent crustal deformation.

ABSTRACT In this paper, we review ~140 yr of investigations about pelagosite, a usually black aragonitic encrustation with a vitreous luster that forms in the splash zone of Mediterranean rocky coasts. Prior to the mid-1920s, the geologic community considered pelagosite to be a separate mineral of uncertain composition, but then in 1926, Italian mineralogist Ettore Onorato determined that pelagosite has the same structure as aragonite (orthorhombic CaCO 3 ), and also that it contained cells of blue-green algae (i.e., cyanobacteria). Once pelagosite was declassed from the status of a mineral, and its name was eliminated from catalogues and textbooks, Onorato’s documentation of the cyanobacterial cells contained in this encrustation seems to have fallen into almost total oblivion during the rest of the twentieth century. We revisited pelagosite in its original type locality, the remote southern Adriatic island of Pelagosa (today’s Croatian island of Palagruža), as well as in the Dalmatian island of Hvar. Using modern analytical methods and techniques, we redefined the mineralogical and geochemical composition of pelagosite, the nature and significance of its microbial content, and the origin of its pisolitic “tree-ring” internal structure, which probably reflects cyclic climate changes.

The Bottaccione Gorge at Gubbio, Italy, a source of many discoveries in Earth history, was first recognized as an outstanding geological section by Guido Bonarelli (1871–1951). Bonarelli is remembered today mainly for the meter-thick Bonarelli Level, the local manifestation of oceanic anoxic event 2 (OAE 2), which he first recognized and described. Setting aside Bonarelli’s long and distinguished career as a petroleum geologist in Borneo and Argentina, this paper concentrates on his role in the long and difficult effort to date the Scaglia rossa pelagic limestone of the Bottaccione Gorge and the surrounding Umbria-Marche Apennines. Old photographs show a barren Bottaccione Gorge a century ago; Bonarelli apparently had much better outcrops than we do today, after reforestation shortly before the middle of the twentieth century. In the absence of macrofossils, and with the inability to extract isolated foraminifera from these hard limestones, the Scaglia was dated indirectly in the late nineteenth century, and believed to be entirely of Cretaceous age, implying errors as great as 40 m.y. We can now understand why this dating seemed satisfactory at the time, because it did not conflict with Charles Lyell’s view that there should be a huge hiatus corresponding to a major faunal overturn like the Cretaceous-Paleogene (K-Pg) boundary, and because thrust faulting that contradicted it had not yet been discovered. The K-Pg boundary was correctly placed within the Scaglia in 1936 when Otto Renz identified the foraminifera in thin section. Renz wrote with pleasure of a field trip with Bonarelli, who later presented Renz’s new dating to the Società Geologica Italiana on a 1940 field trip to Gubbio. These two are the predecessors of all the geologists who have worked in the Bottaccione Gorge since the Second World War.

The doctoral thesis of Otto Renz on the Scaglia in the Central Apennines, published in 1936, led the foundation for the enduring fame of the region of Gubbio, Italy, as a special place to study the geohistory of the Cretaceous and the Paleogene.

The Mesozoic and Paleogene pelagic carbonate rocks of the Northern Apennines have proved to be a fertile source for paleomagnetic research. Investigations of the magnetic properties of the Scaglia limestones illuminated the processes by which they were magnetized. Their directions of remanent magnetization contributed to an understanding of the geodynamic history of Adria as a promontory of the African plate and have been used to refine the Mesozoic part of the African polar wander path. Magnetic stratigraphy in the Umbrian sequence and in similar facies in the southern Alps has established an independent record of geomagnetic polarity history since the Middle Jurassic. Correlation with the record derived from interpretation of oceanic magnetic anomalies mutually confirmed the global nature of the polarity history. This enabled the dating of plate motions and the development of a geomagnetic polarity time scale for the late Mesozoic and Cenozoic.

Soft-sediment deformation structures crop out in the Lower Cretaceous succession of the Gubbio anticline in the Umbria-Marche Apennines of Italy. The deformation interval is ~13 m thick and occurs between the upper Hauterivian–lower Aptian Maiolica Formation and the Aptian Marne a Fucoidi Formation. It can be observed along the anticline for a distance of 12 km. Different types of deformation structures are distributed in several outcrops, with detachment extensional structures prevailing in the southeast sector. Imbricated slides, slump structures, and chaotic layers are distributed vertically and longitudinally in the middle and/or lower part of the deformed sediments. In the northwest sector of the anticline, compressional duplex structures can be considered the lower section of a large sediment failure. Geometrical and kinematic analysis of the fold axis trends and sliding surfaces have led to infer a single, large gravitational event possibly Albian in age. The synsedimentary deformation could be activated by several internal trigger mechanisms induced by external regional tectonic events such as earthquakes. An orthogonal system of calcite veins crossing the limestone layers represents the primary pathway for fluid-driven breaching of joint seals. These fluids can be related to the significant increase in the total organic carbon in the Hauterivian–Aptian layer of the Maiolica and Marne a Fucoidi Formations. This suggests the possibility that the limestone layer, sandwiched and sealed between clay of the organic-rich black shales, could have favored a pore pressure increase approaching lithostatic stress. With a thin overburden, lithostatic stress is more easily reached at low hydrostatic pressure. This slump sheet occurrence suggests the existence of a local paleoslope dipping toward the north-northwest, where the mass involved in the deformation is distributed over an estimated area of 60 km 2 for a volume of 0.8 km 3 of displaced sediments. The restoration and rotation of the slump fold hinges to the Early Cretaceous direction, in line with available paleomagnetic data, have shown that the strike of the slope corresponds to the main trend of the oldest Jurassic extensional lineaments and is linked to transform faults of the westernmost Tethys rifting systems.