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Abstract: Alpine orogens in the central Mediterranean region have revealed the concomitance of crustal extension in back-arc domain and crustal shortening in frontal domain. Quantitative data of deformation in the frontal orogenic wedges are necessary to understand how the shortening-extension pair evolves in terms of structures, orogenic transport, timing, and exhumation rate. This paper deals with kinematics and ages of the frontal thrust systems of the Calabria-Peloritani Arc (Italy) exposed in the eastern Sila Massif. We first present structural fieldwork, onshore and offshore well log data, and new apatite fission-track (AFT) thermochronology. Then, we describe the structural architecture of the studied area as an ENE-verging stacking of thrust sheets involving basement units and syn-orogenic sediments. The AFT study documents that thrust sheets entered the partial annealing zone from 18Ma to 13Ma. This Early-Middle Miocene thrusting phase was coeval with exhumation of high-pressure/low temperature metamorphic rocks in the hinterland of the orogen (Coastal Chain area), mainly driven by top-to-the-W extensional tectonics. Opposite kinematic shear senses (contractional top-to-the-E and extensional top-to-the-W) and different exhumation rates (slow in the frontal, more rapid in the hinterland) are framed in a tectonic scenario of a critically tapered orogenic wedge during the eastward retreating of the Apennine slab. [Copyright &y& Elsevier]

Summary: The Porto Torres (NW Sardinia) coastal aquifer is hosted in the carbonate rocks of the Miocene succession, which fills a NNW oriented half-graben. This aquifer is an important contributor to the fresh water supply of the local area. It is increasingly being degraded by salinization processes, mainly associated with intense groundwater over-exploitation. A combined hydrochemical and hydrogeological study has been carried out to identify the origin of the salinity in the groundwater. The behavior of the major ions showed that the changes in the chemical composition of the groundwater have been mainly controlled by the encroachment of seawater, accompanied by cation exchange reactions. Since seawater intrusion is a dynamic process, an Hydrochemical Facies Evolution Diagram, HFE-D () approach was taken to establish whether the aquifer was in the seawater intrusion or in the freshening phase. The assessment model developed provides regional authorities with a basic tools for sustainable water management in the framework of multi-disciplinary research activities aiming to combat and/or mitigate desertification and land degradation processes. [Copyright &y& Elsevier]

Abstract: The western segment of the Sicilian Apennines (southern Italy) is affected by poly phase deformation characterized by non-coaxial structural associations. In particular, this study is focused on two narrow ∼E–W oriented structural and topographic culminations of the fold and thrust belt (Mt. Kumeta and Rocca Busambra ridges), resulting from the exhumation of a deep-seated tectonic unit. A detailed field mapping and meso-structural analysis reveals that since Pliocene time the region was tectonically controlled by the propagation of two major NW–SE oriented right-lateral shear zones and associated structures that often propagated along inherited discontinuities. In particular, the left-stepping geometry and the sense of motion of these regional strike-slip fault systems produced in the overlapping area a wide rhomboidal-shaped contractional region characterized by the occurrence of double-verging ∼E–W striking compressive structures. These bound the Mt. Kumeta and Rocca Busambra carbonate ridges, forming a pair of pop-up structures which link the coeval transcurrent boundary faults. Field data show that contractional structures are affected by significant bending along strike that increases close to the major shear zones. Structural rotations around the vertical axis allowed the carbonate ridges to develop a typical sigmoidal shape. The topographic expression and the internal structural architecture, compared with experimental models describing deformations associated with segmented strike-slip faults, suggest that the analyzed segment of Sicilian fold and thrust belt can be interpreted as a restraining stepover in which crustal shortening, exhumation and vertical axis rotation occurred. Moreover, field data, compared to the subsurface setting imaged by the analysis of available geophysical data (e.g. gravimetric maps and available/interpreted seismic profiles), reveal that, since Pliocene times, the restraining stepover deformation was transversally superimposed on a pre-existing NE–SW oriented thrust and fold system related to the Miocene Africa–Europe collision. [Copyright &y& Elsevier]

Abstract: The Oligo-Miocene carbonates pertaining to the Bolognano Formation, cropping out at the Majella Mountain, Italy, are diffusely crosscut by bed-parallel structural elements such as compaction bands and pressure solution seams. These bed-parallel structural elements formed under a vertical loading, during the progressive burial of the carbonates. The present work focuses on the control exerted on their development and distribution by compositional, sedimentological and pore network characteristics of the studied carbonates. The main results are consistent with the following statements: (i) bed-parallel compaction bands developed only within the poorly cemented, porous grainstones (2D porosity > 10%; 3D porosity > 15%); (ii) distribution of these bands was strongly controlled by both sorting and sphericity of the carbonate grains, as well as by the amount of intergranular macroporosity; (iii) bed-parallel pressure solution seams formed, mainly, within the fine-grained packstones, which are characterized by small amounts of clayish matrix (2–4% of total rock volume), and well-sorted, spherical carbonate grains. Considering the impact that burial-related, bed-parallel structures may have on fluid flow, the results provided in this contribution can help the management of subsurface geofluids, and overall prediction of carbonate reservoir quality, by mapping/simulating/assessing carbonate facies. [Copyright &y& Elsevier]

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]

In this paper we present a model for the growth of a maar-diatreme complex in a shallow marine environment. The Miocene-age Costa Giardini diatreme near Sortino, in the region of the Iblei Mountains of southern Sicily, has an outer tuff ring formed by the accumulation of debris flows and surge deposits during hydromagmatic eruptions. Vesicular lava clasts, accretionary lapilli and bombs in the older ejecta indicate that initial eruptions were of gas-rich magma. Abundant xenoliths in the upper, late-deposited beds of the ring suggest rapid magma ascent, and deepening of the eruptive vent is shown by the change in slope of the country rock. The interior of the diatreme contains nonbedded breccia composed of both volcanic and country rock clasts of variable size and amount. The occurrence of bedded hyaloclastite breccia in an isolated outcrop in the middle-lower part of the diatreme suggests subaqueous effusion at a low rate following the end of explosive activity. Intrusions of nonvesicular magma, forming plugs and dikes, occur on the western side of the diatreme, and at the margins, close to the contact between breccia deposits and country rock; they indicate involvement of volatile-poor magma, possibly during late stages of activity. We propose that initial hydromagmatic explosive activity occurred in a shallow marine environment and the ejecta created a rampart that isolated for a short time the inner crater from the surrounding marine environment. This allowed explosive activity to draw down the water table in the vicinity of the vent and caused deepening of the explosive center. A subsequent decrease in the effusion rate and cessation of explosive eruptions allowed the crater to refill with water, at which time the hyaloclastite was deposited. Emplacement of dikes and plugs occurred nonexplosively while the breccia sediment was mostly still soft and unconsolidated, locally forming peperites. The sheltered, low-energy lagoon filled with marine limestones mixed with volcaniclastic material eroded from the surrounding ramparts. Ultimately, lagoonal sediments accumulated in the crater until subsidence or erosion of the tuff ring caused a return to normal shallow marine conditions. [ABSTRACT FROM AUTHOR]

Abstract: Oreopithecus bambolii is one of the few hominoids that evolved under insular conditions, resulting in the development of unique adaptations that have fueled an intensive debate. The palaeoenvironment associated with this great ape has been the subject of great controversy as well. On the one hand, palaeobotanical data indicate that Oreopithecus likely inhabited mixed mesophytic forests interrupted by swamps; on the other hand, an abundance of hypsodont bovids points towards the existence of dry and open environments. Here, we provide a new approach based on the ecomorphology of the extinct endemic Muridae (rats and mice) of the so-called Oreopithecus faunas. Our results show that the successive species of endemic insular murids (Huerzelerimys and Anthracomys) evolved a number of adaptations observed only in extant family members that include significant proportions of grass in their diet. While this fits the pattern exhibited by large mammals, it contrasts with the available palaeobotanical information, which indicates that grasses were minor components of the vegetation. This contradiction may be explained because these endemic murids may have been adapted to the consumption of particular food items such as hard parts of aquatic plants (as shown by some extant murid species). However, because it is unlikely that the remaining herbivore mammals were adapted to this diet as well, we favour an alternative hypothesis that takes into account the peculiar ecological conditions of insular ecosystems leading to a density-dependent selective regime with strong competition. Such a regime would promote the selection of dental adaptations to increase feeding efficiency and durability of the dentition (such as hypsodonty) as seen in some fossil insular ruminants. This hypothesis requires further testing, but may partly account for parallel evolution of dental traits in phylogenetically unrelated insular mammals. [Copyright &y& Elsevier]

Abstract: Tuscany (Central Italy) is a key area for studying the Messinian Salinity Crisis and overlying Lower Pliocene deposits due to the high number and excellence of the outcrops. Although the Miocene/Pliocene transition is well exposed and suitable for detailed analyses, a high-resolution integrated stratigraphic study of such a crucial time span for the geological history of the Mediterranean has never been attempted. In the Fine Basin (Central Tuscany), the Cava Serredi section is one of the best exposures of the upper Messinian–Lower Pliocene transition of the Northern Apennines. The Miocene/Pliocene boundary corresponds to a surface separating thinly laminated lacustrine (“Lago-Mare”) marls from homogeneous circalittoral to upper bathyal marly clays. Detailed quantitative micropalaeontological analyses have been performed on 111 samples from the 22m-thick Lower Pliocene succession. They resulted in the improvement of the biostratigraphic resolution of the basal Zanclean interval due to the recognition of several chronologically constrained bioevents typical of the Mediterranean region and based on benthic and planktonic foraminifera and calcareous nannofossils. Moreover, to unravel cyclical patterns of deposition, and given that the investigated succession shows no evident lithological pattern, micropalaeontological analyses have been coupled with calcium carbonate content variations. The latter revealed more-regular fluctuations, which are especially evident if the exclusive contribution of the planktonic foraminifer fraction (PCaCO3) is considered. Spectral analysis of the CaCO3 curve indicates that sedimentation occurred under the control of Earth''s precession. This datum is also confirmed by the cyclical patterns of Neogloboquadrina acostaensis and Sphenolithus spp. among foraminifers and nannofossils, respectively. According to the proposed cyclostratigraphic and astrochronological reconstruction, the Lower Pliocene interval of the Cava Serredi section consists of eight precession-controlled cycles ranging from the i-cycle 510 (5.33Ma) to the i-cycle 494 (5.16Ma). Finally, the comparison with other astronomically calibrated sections, including the Zanclean GSSP (Eraclea Minoa, Sicily), allowed us to prove the completeness of the basal Zanclean interval of the study section and to state that Pliocene re-flooding after the Messinian Salinity Crisis occurred synchronously with respect to other deeper sectors of the Mediterranean Basin. [Copyright &y& Elsevier]

Abstract: This study has the aim of dating the latest Miocene Hominoid Oreopithecus bambolii bearing succession of the Baccinello–Cinigiano Basin (BCB) in southern Tuscany (Italy). Since the 1960s biochronology has been the source for rough age estimations. Geochronological techniques have started to provide significant time constraints after the absolute dating obtained from a single point in the BCB, where a relatively thick and continuous lithostratigraphic record is found together with a succession of several mammal sites. Chronological control of the sedimentary succession and age range of Oreopithecus faunal assemblage has nowadays only been possible with the characterization of the magnetostratigraphy of the BCB sedimentary succession. This study demonstrates that: i) the oldest Oreopithecus bearing sediments in BCB (V1) has an age older than 8.1Ma; ii) the IGF 4883V Oreopithecus from Trasubbie creek has an age of 8.1–7.7Ma; iii) the youngest Oreopithecus remains (from the so called V2 assemblages) have an age between 7.1 and 6.7Ma; iv) the Oreopithecus chronologic range within the BCB is about 1.5Ma long bracketed between 8.3 and 6.7Ma; v) the post-Oreopithecus faunal complex V3-bearing deposits, likely to have an age between 6.7 and 6.4Ma, belonging to the very early MN13 unit (early Messinian); and finally, vi) Oreopithecus is confirmed to be the youngest dryopithecine record from Eurasia, extending his last occurrence into the early Messinian. [Copyright &y& Elsevier]

Abstract: This paper deals with the effects of pre-existing fractures on the development of damage zones related to meter and decameter strike-slip faults, which affected Late Oligocene-Early Miocene sandstone in the Calcione area, southern Tuscany (Italy). Strike-slip faults dissected rock masses locally affected by pervasive, pre-existing fractures related to previous deformational events. Two different domains were identified: rock masses affected and unaffected (or relatively unaffected) by pre-existing fractures. Strike-slip faults affecting the two domains made it possible to compare the different configurations of fracture patterns related to isolated or interacting fault segments. New data is provided on scaling relations between: i) fault length and the length of related fractures; ii) mean step length and width for overstepping fault segments; iii) angular values at the intersection of the fault plane and related fractures. Scaling relations obeyed a positive power law for faults dissecting sandstone unaffected by pre-existing fractures. On the contrary, no scaling relations were recognized for faults dissecting sandstone affected by pre-existing fractures. The development of strike-slip faults on rock masses affected by pre-existing fractures can simulate splays apparently related to faulting. Three main points were categorized for detecting deceptive cases. There is a real chance of a deceptive fracture pattern if: i) the angular values at the intersection of the fault and its fractures (mode I opening fracture) exceed 50° in the wall damage zone; ii) the scaling relation between fault length and maximum fracture length does not fit a power law; iii) fractures acted as shear fractures. The resulting framework provides additional data for understanding the development and architecture of strike-slip faults. [Copyright &y& Elsevier]

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: During the Miocene, hydrocarbon seep-carbonates located atop intrabasinal highs and associated with sediment instability, formed commonly at the deformation front of the Northern Apennine collisional orogen. The parallelism between the structural trend and the distribution of seep-carbonates suggests a close relationship between tectonics and gas/fluid emission. The “Montepetra intrabasinal high” was formed during the closure stage of the foredeep, being related to the synsedimentary growth of an anticline. Field geometry suggests that detachment folding was the leading mechanism of anticline growth and synsedimentary instability along the anticline flanks. Ten different bodies of seep-carbonates occur in the Tortonian–early Messinian sediments: nine in the hinge zone and one in the southern backlimb of the anticline. Foraminiferal study, geochemistry, facies investigation and the three-dimensional geometry of carbonate bodies with respect to the encasing terrigenous sediments indicate a protracted (late Tortonian–early Messinian) activity of fluid migration with re-mobilization and ascent of sediments from the core of the anticline, stabilization of chemosynthesis-related communities, and in-situ brecciation. Seepage atop the intrabasinal high was fed by different circuits: one related to the compaction-dewatering of shallow (Tortonian–early Messinian) sediments, and a deeper one related to the deformation of the anticline core and to the activity of detachment surfaces and of faults propagating through the sedimentary cover. [ABSTRACT FROM AUTHOR]

The Monte Orfano Conglomerate (MOC), exposed in the foothills of the Southern Alps (northern Italy), is one of the few outcrops of sediments documenting the Cenozoic tectonic evolution of the Alpine retrowedge. Calcareous nannofossil biostratigraphy allowed us to constrain the upper part of the MOC, formerly attributed to the Early-Middle Miocene in the type-locality, to the earliest Miocene (Neogene part of the NN1 nannofossil zone). A likely latest Oligocene age is therefore suggested for the bulk of the underlying conglomerates, whose base is not exposed. Deposition of the MOC can be placed within the post-collisional tectonic uplift of the Alps, documented in the Lake Como area by the Como Conglomerate (CC) at the base of the Gonfolite Lombarda Group, and supports the correlation with Upper Oligocene clastic sediments cropping out further to the East, in the Lake Garda and in the Veneto-Friuli areas (“ molassa”). The remarkable difference in petrographic composition between the western (CC) and eastern (MOC) clastics deposited in the Alpine retro-foreland basin highlights the synchronous tectonic activity of two structural domains involving different crustal levels. Whilst the bulk of the CC, that straddles the Oligocene/Miocene boundary, records largely the tectonic exhumation of the Alpine axial chain crystalline complexes, the coeval MOC consists of detritus derived from the superficial crustal section (Triassic to Paleogene sedimentary rocks) of the Alpine retrowedge and constrains the onset of the post-collisional deformation phase of the Southern Alps as not younger than the Late Oligocene. [ABSTRACT FROM AUTHOR]

Abstract: Continuous marine successions covering the Middle Miocene Climate Transition (MMCT; ∼15–13.7Ma) are scarce and the lack of a high-resolution magnetobiostratigraphic framework hampers the construction of astronomically tuned age models for this time interval. The La Vedova High Cliff section, exposed along the coast of the Cònero Riviera near Ancona (Italy), is one of the few Mediterranean sections covering the critical time interval of the MMCT. Starting from an initial magnetobiostratigraphic age model, a robust astronomical tuning was constructed for the interval between 14.2 and 13.5Ma, using geochemical element data and time series analysis. A shift in δ 18O of bulk sediment towards heavier values occurs between ∼13.92 and 13.78Ma and could be related to the Mi3b oxygen isotope event, which reflects the rapid expansion of the East Antarctic Ice Sheet in the middle Miocene. The onset of the CM6 carbon excursion is reflected in the bulk record by a rapid increase in δ 13C at 13.86Ma. Our results confirm the proposition that these events coincide with a 405-kyr minimum in eccentricity and a node in obliquity related to the ∼1.2Myr cycle. From 13.8Ma onwards, distinct quadruplet cycles containing sapropelitic sediments were deposited. This may suggest a causal connection between the main middle Miocene cooling step and the onset of sapropel formation in the Mediterranean. [ABSTRACT FROM AUTHOR]

Abstract: The lower Messinian marine sediments of the Capo San Marco Formation in the Sinis area (Sardinia, Italy) contain extensive carbonate buildups mainly made of microbialites. These microbialites exhibit general thrombolitic fabric and occur in meso-macroscopic scale as dominant cauliflower-like structures, digitations and encrusting rings. All the microbialites are here associated with serpulid tubes and bryozoan colonies. Examination of thin sections from microbialite samples reveal the presence of dense flexuous, not ramified and erect tubular micritic structures, with an external diameter ranging from 30 to 40μm, all characters being very close to those of the Girvanella-type filaments. Although all microbialites show quite similar structural aspects, only two levels contain clearly visible networks of such filaments. The associated marine biota is diverse (cemented, borers, burrowers) related to the available biotopes (hard substrates, fine grained sediment, cavities…). The general scarcity of microbial remains in Messinian microbialites points out to the problem of taphonomic processes allowing a good preservation of microbial structures. The concept of Lagerstätten could well be extended to the preservation of microscopic organisms in the carbonate material. The discovery of Girvanella-like filaments demonstrates the implication of cyanobacterial organisms in the construction processes of the Messinian thrombolitic buildups. Furthermore, it is the first time that Girvanella-like microbialites are documented from Upper Miocene marine rocks. [ABSTRACT FROM AUTHOR]

Terra Nova, 00, 1–7, 2010 The C-isotope composition of a Miocene carbonate succession from the Latium-Abruzzi sector of the Central Apennines was studied to evaluate the influence of local vs . global factors in changing δ13C. We propose that the Oligo-Miocene igneous activity of the Western Mediterranean and the closure of the Indo-Pacific connection influenced climate change and Mediterranean sea-water circulation. The huge Aquitanian–Burdigalian volcanic activity during the formation of the Ligurian–Provençal Basin, with related increase in atmospheric CO2, may have accelerated weathering and hydrological cycling of nutrient inputs in coastal environments. The closure of the Indo-Pacific connection altered the circulation by changing and reversing the western exchange flow. The existence of warm and seasonally humid climate favoured the development of estuarine circulation, which was to lead to a dramatic increase in productivity in the euphotic zone. [ABSTRACT FROM AUTHOR]

Abstract: An integrated analysis of rhodolith assemblages and associated trace fossils (borings) found in hemipelagic Middle Miocene Orbulina marls (Vitulano area, Taburno–Camposauro area, Southern Apennines, Italy) has revealed that both the biodiversity of the constituent components and taphonomic signatures represent important aspects which allow a detailed palaeoecological and palaeoenvironmental interpretation. On the basis of shape, inner arrangement, growth forms and taxonomic coralline algal composition, two rhodolith growth stages were distinguished: (1) nucleation and growth of the rhodoliths, and (2) a final growth stage before burial. Nucleation is characterized by melobesioids and subordinately mastophoroids, with rare sporolithaceans and lithophylloids. The rhodolith growth (main increase in size) is represented by abundant melobesioids and rare to common mastophoroids; very rare sporolithaceans are also present. The final growth stage is dominated by melobesioids with rare mastophoroids and very rare sporolithaceans. Each rhodolith growth stage is characterized by a distinct suite of inner arrangement and growth form successions. Well diversified ichnocoenoeses (Gastrochaenolites, Trypanites, Meandropolydora and/or Caulostrepsis, Entobia, Uniglobites, micro-borings) related to bivalves, sponges, polychaetes, barnacles, algae, fungi, and bacteria are distinguished in the inner/intermediate rhodolith growth stage, while mainly algal, fungal and bacterial micro-borings are present in the outer final growth stage. Rhodolith growth stages and associated ichnocoenoeses indicate significant change in the depositional setting during the rhodolith growth. In the Vitulano area, the Middle Miocene rhodolith assemblages formed in a shallow-water open-shelf carbonate platform, were susceptible to exportation from their production area and then to sedimentation down to deeper-water hemipelagic settings, where the rhodoliths shortly kept growth and were finally buried. Such re-deposition of unlithified or only weakly lithified (i.e. rhodoliths and intraclasts) shallow-water carbonates into deeper-water settings was likely favoured by storm-generated offshore return currents rather than sediment gravity flows. [Copyright &y& Elsevier]

Earth scientists have searched for signs of microscopic life in ancient samples of permafrost, ice, deep-sea sediments, amber, salt and chert. Until now, evidence of cyanobacteria has not been reported in any studies of ancient DNA older than a few thousand years. Here, we investigate morphologically, biochemically and genetically primary evaporites deposited in situ during the late Miocene (Messinian) Salinity Crisis from the north-eastern Apennines of Italy. The evaporites contain fossilized bacterial structures having identical morphological forms as modern microbes. We successfully extracted and amplified genetic material belonging to ancient cyanobacteria from gypsum crystals dating back to 5.910–5.816 Ma, when the Mediterranean became a giant hypersaline brine pool. This finding represents the oldest ancient cyanobacterial DNA to date. Our clone library and its phylogenetic comparison with present cyanobacterial populations point to a marine origin for the depositional basin. This investigation opens the possibility of including fossil cyanobacterial DNA into the palaeo-reconstruction of various environments and could also be used to quantify the ecological importance of cyanobacteria through geological time. These genetic markers serve as biosignatures providing important clues about ancient life and begin a new discussion concerning the debate on the origin of late Miocene evaporites in the Mediterranean. [ABSTRACT FROM AUTHOR]

Abstract: An integrated high-resolution magnetobiocyclostratigraphy including radioisotopic dating and astronomical tuning is presented for the interval between 15.29 and 14.17Ma in the marine La Vedova section in northern Italy. The natural remanent magnetization is carried by the iron sulphide greigite and the resultant magnetostratigraphy can be correlated straightforwardly to the interval ranging from C5Bn.2n to C5ADn in the Astronomically Tuned Neogene Time Scale (ATNTS2004). Spectral analysis on high-resolution magnetic susceptibility and geochemical proxy records in the depth domain and, using our magnetobiostratigraphic age model, in the time domain demonstrate that the various scales of cyclicity in the section are related to astronomical climate forcing. Starting from our initial age model, larger-scale cycles were first tuned to eccentricity. This first-order tuning was followed by tuning the basic cycle to precession and boreal summer insolation using inferred phase relations between maxima in Ca/Al, redox-sensitive elements and Ba, and minima in magnetic susceptibility, and maxima in precession and minima in obliquity and boreal summer insolation. Our astronomical ages for reversal boundaries are supported by analysis of sea floor spreading rates and should replace the existing ages in the ATNTS2004 lacking direct astronomical control. Two major steps in the geochemical proxy records, astronomically dated at 15.074 and 14.489Ma, coincide with abrupt changes in sedimentation rate, and are the result of the combined effect of the ∼400-kyr eccentricity cycle superimposed upon a longer-term climatic or tectonic induced trend. [Copyright &y& Elsevier]

Abstract: In SW Sardinia, the continental Tertiary successions referred up to now to the Cixerri Fm. (Middle Eocene–Lower Oligocene?) have been investigated. Sedimentological analysis suggests these deposits lied down in fluvial environments and comprised between distal braided streams passing eastward to meandering streams/coastal environments (?) under sub-arid climates. The scrutinization of the Cixerri Fm. westernmost successions allowed one to split locally the upper from the lower part based on sedimentological and mineralogical features and indirect dating. Unfortunately, this separation cannot be set everywhere. The few upper outcrops plainly evidenced and well-constrained have been newly named Flumentepido Fm. and assigned to Late Oligocene–Early Miocene: they figure out alluvial fans and proximal braided rivers. This way, the SW Sardinia Tertiary continental sedimentation extends its persistence, contemporaneously changing its tectostratigraphic meaning: from a molassoid context related to the Pyrenean wedge dismantling (Eocene–Oligocene) to a rift-margin succession connected with the opening of the Algero-Provençal back-arc basin due to the Apennine subduction in Oligocene–Miocene times. [Copyright &y& Elsevier]

Abstract: The astronomically tuned marls of the Monte Gibliscemi section, Sicily, constitute an archive to trace the late Miocene palaeoenvironmental conditions (~9.7–7.0Ma) in North Africa. Here we have utilised carbonate content and Al-normalised geochemical proxies to trace changes in terrigenous source area and bottom-water ventilation. The terrigenous input into the section is dominated by North African river systems draining into the Eastern Mediterranean. The proxy parameters indicate that the palaeoenvironmental conditions in North Africa were humid from 9.5Ma onward with high fluvial input to the Mediterranean. Increases in the Si/Al and Mg/Al ratios occurred from 8.4 to 8.2Ma and from 8.05 to 7.75Ma, with maximum values similar to those of Messinian diatomites. These peaks indicate conditions of enhanced biosiliceous productivity and the presence of authigenic clay formation. Sluggish water circulation in the Mediterranean during those times is inferred from the Mn/Al and V/Al behaviour. Late Miocene changes of the Betic (southern Spain) and Rifian (Morocco) Mediterranean–Atlantic gateways are interpreted as the driving force for the changes in water circulation and the transgression associated with the opening of the Rifian corridor is interpreted to occur at 7.8Ma. [Copyright &y& Elsevier]

Abstract: Benthic foraminifera from seep carbonates and from enclosing non-seep marls present within Miocene formations in the Northern Apennines (Italy) were investigated as proxies of methane seepage in the marine environment. Negative δ13C values of benthic foraminifera from these seeps indicate unambiguously the local influence of CO2 produced by microbial anaerobic methane oxidation on the benthic ecosystem. Calcareous species living within methane seeps display δ13C values ranging from −9.04 to −25.74‰ PDB, whereas in the coeval surrounding marls the same species display δ13C values from −1.54 to 0.62‰ PDB. Different species (Cibicidoides kullenbergi, C. pachyderma, Siphonina rethiculata, Planulina wuellestorfi, Bolivina miocenica, Brizalina dilatata, Vulvulina pennatula, and Cibicides praecinctus) in different seep carbonates indicate that benthic foraminifera, independently of the taxa and of microhabitat preferences, have more negative δ13C values than those found in the enclosing marls. Therefore each species represents a potential proxy for past seafloor methane emissions. In addition to the calcareous species, the agglutinated species Vulvulina pennatula displays −27.5‰ PDB in seep carbonates against −2.69‰ PDB in the enclosing marls. This suggests that the species utilized strongly 13C depleted carbonate particles from authigenic carbonate precipitation during the mineralization of their tests. [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]

Abstract  Hydrogeological and geophysical surveys confirm that the aquifers of the Capoterra plain in Sardinia (Italy) constitute a complex, multilayer system. In the north-east of the plain, this system is composed of a shallow aquifer of recent alluvium and a deeper aquifer separated from the former by a clay layer; in the south-west there is no separation between the two aquifers. The deepest and most important member of the multilayer aquifer system is situated at the transition from Quaternary to Miocene sediments. With respect to deep structures and stratigraphy, several differentiations inside the Miocene sedimentary filling, whose overall thickness is in the order of 300 m, have been found. The combined interpretation of several datasets allows the Capoterra plain to be reliably modelled from surface to a depth of several hundreds of metres and provides the possibility of finding deeper groundwater resources. Concerning the latter, since Miocene materials are known to be impermeable in the middle of the plain, in contrast to the aquifers hosted in the Quaternary sediments and alluvium, the probability of finding fresh water at a depth of less than 350–400 m is very low. The condition of seawater intrusion affecting the aquifers is also elucidated. [ABSTRACT FROM AUTHOR]

Abstract: A high-resolution integrated stratigraphy including biostratigraphy, magnetostratigraphy, tephrostratigraphy and cyclostratigraphy is presented for the upper Tortonian and lower Messinian (Upper Miocene) at Monte dei Corvi. Numerical age control comes from a combination of magnetobiostratigrapic dating and astronomical tuning, while radioisotope dating of ash layers produced less reliable ages. The deep marine succession is characterized by large-scale non-repetitive stratigraphic changes allowing the discrimination between a Lower, Brownish, Rossini and Euxinic Shale Interval. The sedimentary cycles, which occur superimposed on these large-scale changes, are related to astronomical climate forcing. Astronomical tuning of the sedimentary cycles provides not only absolute ages for biostratigraphic events, reversal boundaries and volcanic ash layers, but also for the observed non-cyclic changes. These can be linked to environmental and geodynamic changes in the Mediterranean region preceding the Messinian Salinity Crisis. The beginning of the Brownish Interval marked by tripartite cycles at 8.017 Ma coincides with tectonic re-arrangements in the Mediterranean, such as compression in the Betics and opening of the Rifian corridor. At 7.616 Ma the change to the calcareous Rossini Interval can be linked to tectonic uplift in the northern Apennines and the deepening of the Rifian corridor, while the Betic corridor became restricted coinciding with the end of evaporite deposition in the eastern Betics. The change to euxinic shales at 7.168 Ma reflects basin-wide restriction marked by diatomite and sapropel formation in the Mediterranean basin related to the severely constricted Betic and Rifian corridors. The occurrence of a tripartite construction of cycles in the euxinic shales at 6.719 Ma coincides with diatomite formation in the eastern Mediterranean, uplift and shallowing in the Northern Apennines and further constriction of the Atlantic gateways. We conclude that late Tortonian–early Messinian tectonic and environmental events occur remarkably synchronously in the Mediterranean basin and most likely result from a combination of geodynamic processes and eccentricity-controlled climatic changes. In combination with the upper Serravallian and lower Tortonian interval, which includes the formal Tortonian Global Stratotype Section and Point (GSSP), the Monte dei Corvi is the only complete section in the Mediterranean covering the entire Tortonian Stage. We therefore propose the Monte dei Corvi section as Tortonian reference section, particularly for the Mediterranean region. In addition, it may serve as a unit-stratotype for the Tortonian. [Copyright &y& Elsevier]

Abstract: In the area of Punta Funtanas (Arbus, Central-West Sardinia) some small surfaces of Miocene limestones crop out, partially covered with Quaternary calcarenites and Plio-Quaternary basalts. The biggest of these outcrops forms a fossil wave-cut shore platform of up to 50 m wide with an altitude above sea level of approximately 4–5 m. On this platform a wide variety of dissolution landforms can be observed. These morphologies are related to the influence of the seawater (zone of wave action, marine splash and spray zone, up to progressively more continental environments) and to biokarst processes (erosional action of marine organisms, algae and micro-organisms) and are arranged in bands parallel to the coast, corresponding to different morphological zones. This paper describes all the karst landforms observed in this coastal area from a morphological and genetic point of view. [Copyright &y& Elsevier]

Apatite fission-track analyses on samples from eastern Sardinia document a complex tectonic history, whose reconstruction is problematic because of the reactivation of faults and structures at different times from Jurassic to Miocene. The oldest ages (150–154 Ma) have been detected on the southern margin of the Gulf of Orosei and are related to the extensional tectonics that characterize the European passive margin during Early and Middle Jurassic times. Thermal modelling of these data allows reconstruction of the burial history of the Mesozoic basin and estimation of a sedimentary thickness of 2000 m. Part of these sediments was eroded during the following uplift, documented by mid-Cretaceous fission-track ages. A further exhumation episode of Eocene age has been revealed by fission-track data on granite samples, and has been inferred to be related to the Alpine orogenic phase. This tectonic episode caused the exhumation of crustal blocks bound by faults that were finally reactivated during the Late Oligocene–Early Miocene. [ABSTRACT FROM AUTHOR]

Abstract: Two possible alternative interpretations of the claimed Zanclean age () of two historical lithostratigraphic units of the Northern Apennines, usually referred to as Late Messinian in age and recording the so called Lagomare final event of the Messinian salinity crisis (MSC), are here discussed. The wrong age attribution of the Colombacci and “tetto” Fms. is ruled out based on data from the Maccarone and other sections showing that the Colombacci-Argille Azzurre Fm. boundary is basin wide synchronous and coincident with the Miocene-Pliocene boundary as far as it has been formally defined in the Eraclea Minoa GSSP. Alternatively, the opportunity of emending the Zanclean GSSP to a stratigraphically lower horizon recording the first evidence of marine influences in the Mediterranean following the MSC peak, seems not suitable, as (1) the marine signature of uppermost Messinian deposits is weak and still controversial and (2) no significant bio- and magnetostratigraphic events, well chronologically defined and recognizable at a global scale appear to be available to such a purpose. [Copyright &y& Elsevier]

This paper reports the results of a study of more than 2400 specimens in the collection of fossil vertebrates from Fiume Santo in north-west Sardinia. This locality represents the westernmost documentation of the Tusco-Sardinian palaeobioprovince, which was in existence during the late Tortonian in the North Tyrrhenian area. During the Tortonian, the region that presently corresponds to southern Tuscany and the Sardinian Massif (Central Italy) was occupied by a complex of large islands characterised by endemic vertebrate populations. Morphological features, adaptations and trophic structure (e.g. low diversity and scarce carnivore taxa), mainly in the mammal faunas, attest to a long period of isolation from the continental palaeobioprovinces of the Mediterranean and Central Europe. The greatest numbers of fossil remains of the well-known endemic Oreopithecus fauna of the so called V0–V2 assemblages, are found at several sites in southern Tuscany (e.g. Montebamboli, Casteani, Baccinello). In Sardinia this endemic fauna occurs only at the Fiume Santo locality, from which 11 taxa have been recognized: Crocodylia indet., Chelonii indet., Oreopithecus bambolii, Mustelidae indet., Eumaiochoerus cf. E. etruscus, Umbrotherium azzarolii gen. et sp. nov., Tyrrhenotragus gracillimus, Bovidae gen. et sp. indet. (?Neotragini), Maremmia cf. M. lorenzi, Etruria viallii gen. et sp. nov., Turritragus casteanensis gen. et sp. nov. Analysis of these fossils and comparison with material from localities in Tuscany has led to a re-evaluation of the latter and to the description of three new endemic taxa among the ruminants. [ABSTRACT FROM AUTHOR]

The article describes a new stomatopod crustacean species called lenisquilla californiensis from the collections of the Museo Civico di Storia Naturale in Milan, Italy. It mentions that the species is belong to the superfamily Squilloidea and is originated from the Miocene of California. Information of the analysis about the physical form of the species is offered. It notes that the researchers had encountered difficulties in the reconstruction of the species' dactyls due to their preservation.

Abstract: A leaf physiognomic analysis has been carried out on 980 specimens of Messinian leaves collected during the last three decades of the 20th century from the Gessoso Solfifera Formation (Messinian, Late Miocene) in NW Italy. The material is stored at the F. Eusebio Museum of Alba, and originates from a few sites located in close proximity to each other in the valley of the Tanaro River near Alba. According to recently published age models, the studied plant-bearing sites can be dated between 6.0 and 5.7 Ma. The physiognomic analysis was preceded by a taxonomic one, which allowed separation of 74 to 77 dicotyledonous taxa (morphotypes). The botanical affinity of a large proportion of the taxa is not yet defined, because they either belong to the so-called “leguminosoid” types or consist of entire-margined leaves with a coriaceous texture, whose affiliations with a known plant family are not definable solely on the basis of gross morphology. Several recently published univariate and multivariate correlations between climate and leaf physiognomy were applied to the individual floras in order to estimate selected palaeoclimatic parameters. The results obtained for the two richest assemblages, as well as the combined flora from all localities, point to warm-temperate and humid palaeoclimatic conditions, also indicated by the taxonomic composition of these floras. One other assemblage, which consists of fewer taxa, provides significantly lower temperature and precipitation estimates. However, in this case, it is rather likely that the estimates have been influenced by the low number of taxa, caused by taphonomic biases, reducing the representation of entire-margined taxa. Our results imply that at least some existing leaf physiognomic techniques can reliably be used for the reconstruction of palaeoclimatic conditions based on floras from Europe, although previous data from other European floras suggested that some of these methods may produce erroneous results. [Copyright &y& Elsevier]

Miocene volcanic rocks from northeast of Lopburi, Thailand, include a suite of highly potassic (<6.3% K2O) perlitic rhyolites that are similar chemically to rhyolites from Sardinia (which are also perlitic) and Vulcano. Electron microprobe analysis using a defocussed beam has shown that glass compositions contain up to 12.9% K2O (0.9% Na2O), and within the same samples spherulites are enriched in Na2O (<6.2%) and depleted in K2O (2.1%). The perlitic rhyolites contain up to 4% water of meteoric origin; from Fourier transform infra-red spectroscopy data, expansion on heating involves a reduction in both hydroxyl and molecular water contents. When expanded using a laboratory test furnace, specific gravities as low as 26 kg/m3 have been achieved for a 0.15–0.3-mm feed size fraction (reference perlite ores from Milos and Sardinia gave 47 and 33 kg/m3, respectively), and 10 kg/m3 for a 0.5–1-mm fraction separated after expansion. Expansion involves the loss of fluorine from the perlite, presumably as HF; unexpanded perlite contains 90–550 mg/kg F, which is reduced on expansion by 4–65%. Water-soluble fluorine after expansion is increased by a factor of 10 up to 3.3 mg/kg. Expansion also increases the availability of K to plants by a factor of up to 6, with a maximum available K content of 1245 mg K/kg perlite. This contrasts markedly with the chemically inert character of other, commercial, perlites, suggesting that the distinctive K-enrichment of the perlitic rhyolite has given a raw material capable of generating products with nutritional functionality for plant growers. [ABSTRACT FROM AUTHOR]

Abstract: In this paper the ostracod assemblages recovered from several brackish Late Miocene Italian deposits have been analysed from a palaeobiogeographical perspective. During late Tortonian-early Messinian it is possible to recognize in Italy rich ostracod assemblages characterized by a wide contingent of taxa with central European or Mediterranean affinity, while only few brackish and freshwater ostracods show Paratethyan affinity. The recognized composition of the ostracod assemblages matches the palaeogeographic setting of the palaeo-Mediterranean/Paratethys at that moment. In fact during late Tortonian-early Messinian the palaeo-Mediterranean and Paratethysian domains were divided and, even if the connection via the present Marmara Sea-Strimon Basin was still open, the different salinity between them represented an ecological barrier, preventing faunal exchanges. Since normal aquatic migration was impossible, it must be assumed that the Paratethyan-like taxa entered the palaeo-Mediterranean area via passive dispersal by aquatic birds. On the contrary, the ostracod assemblages from the Italian Lago-Mare deposits show the absolute predominance of Paratethyan taxa, which, according to the known palaeogeographic setting during the late Messinian Lago-Mare event, could actively migrate from the Paratethys domain, colonizing the palaeo-Mediterranean, whose endemic fauna was severely impoverished by the Messinian salinity crisis and the following water dilution. [Copyright &y& Elsevier]

Abstract: Vertebrate remains from the lower Burdigalian (early Miocene) carbonates of Montagna della Maiella, central Italy, are described. These remains mostly consist of teeth belonging to 11 elasmobranch taxa (Carcharias acutissima, Carcharias cuspidata, Carcharodon subauriculatus, Isurus hastalis, Isurus oxyrinchus, Isurus sp., Parotodus benedeni, Hemipristis serra, Galeocerdo aduncus, Galeocerdo contortus, Negaprion cf. eurybathrodon), eight teleost taxa (Diplodus sp. and two indeterminate sparids, Labrodon sp., Trigonodon jugleri, Sphyraena sp., Chilomycterus sp., Diodon sp.), an indeterminate crocodile, and two odontocete cetaceans (Squalodon sp. and an indeterminate kentriodontid). Paleoenvironmental and paleogeographical implications are discussed. [Copyright &y& Elsevier]

Abstract: The Mondragone 1 well, drilled in 1968 by Agip, for hydrocarbon exploration, cut across siliciclastic fine-to-coarse-grained upper Miocene–Quaternary deposits, for a total depth of 2002 m. Thirteen cores have been recovered from 495 down to 2002 m. This paper deals with both the results of the biostratigraphical analyses performed on a new sampling of the cores and the significance of the well stratigraphy in the context of the late Messinian Lago–Mare episode in central Mediterranean. The Lago–Mare biofacies has been characterised from 675 down to 2002 m by the ostracod assemblages that are made of species belonging to the Loxocorniculina djafarovi Zone, as defined by Carbonnel [Carbonnel, G., 1978. La zone a Loxoconcha djaffarovi Schneider (Ostracoda, Miocène supérieur) ou le Messinien de la Vallée du Rhône. Rev. Micropaleontol. 21, 106–118.] (e.g. L. djafarovi, Loxoconcha eichwaldi, Cyprideis anlavauxensis, Amnicythere palimpsesta, Zalanyiella venusta). Thus, the Lago–Mare deposits have a true thickness of about 938 m since the strata show a mean dip value of 45°. Similar thickness (530 m) has been measured in the pre-Pliocene sediments drilled at ODP Site 652, which can be correlated with Mondragone 1 by the occurrence of brackish-water forms. In both these areas syn-rift depositional processes have been suggested to explain the unusual thickness of the late Messinian sediments. Data from seismic lines have been used to reconstruct the geometry and the structural setting of the Garigliano Basin during the latest Messinian. Moreover, the analysis of the SP log integrated with the palaeoecological indications from the ostracod assemblages allows us to suggest a possible sequence stratigraphy evolution of the Garigliano Basin during the late Messinian Lago–Mare episode. Different tectonic behaviour with differences in subsidence rates between the northern and the southern Tyrrhenian Basin have been suggested since the uppermost Messinian syn-rift clastic wedges recognized in the onshore of northern Latium and Tuscany show thickness lower than that drilled at the ODP Site 652 and at the Mondragone 1 well. [Copyright &y& Elsevier]

Abstract: During the Miocene time, the Atlas-pelagian block, which is limited northward by the atlasic-alpin chain of North Africa-Sicily, southward by the Gafsa–Jeffara–Azizia fault and eastward by the Malta escarpment, resulted from the extension-compression regime, mainly controlled by the subduction–collision processes. This regime induced the opening of many Miocene microbasins, which have been infilled by silicoclastic materials showing lateral and vertical facies variations and several hiatus associated to tectonic and stratigraphic unconformities. Excepting the very local transgressive regimes, such as those of Langhian and Messinian periods, most of the Miocene deposits took place on internal platforms, especially at the NE part of the country. The fluviodeltaic and alluvial sediments are, in fact, lateral equivalents which infilled the valley and depression enclosed systems towards the SW. In this context (rapid facies variations in time and space, superposition of tectonic and eustatic unconformities, climatic variations, rare or absent stratigraphic markers…), some controversies remain as regards the correlation and dating of these series. This work consists of a study of the lateral and vertical facies and thickness variations, coupled to the identification of the main unconformities. It is also a study of significance of the main sedimentological mechanisms and an inventory of the different palynological and paleontological content of the sediments. The aim of this work is to propose a new vision on the Miocene deposits in Tunisia along a NE–SW axis. Then, using these data, we have correlated the different lithological formations, discuss their age and, finally, proposed paleogeographical drafts for them. [Copyright &y& Elsevier]

Metre-scale siliciclastic–carbonate cycles are the basic depositional motif of the lower Miocene Guadagnolo Formation outcropping in the central Apennines. The mechanisms which formed the mixed-lithology cycles are still a matter of debate. The mixed siliciclastic–carbonate system discussed in this paper provides a new case study to illustrate the role of orbital forcing in controlling the facies evolution and cyclic stacking of small-scale sequences deposited on the outer sector of a ramp. Two sections are discussed that display mixed siliciclastics and carbonates arranged in upward-shallowing cycles. Each cycle shows an upward decrease in the terrigenous input and a parallel increase in benthic fauna. Time-series analyses indicate the cyclic carbonate-terrigenous pattern to be largely controlled by orbital forcing in the Milankovitch frequency band. Coupling of climate change and sea-level fluctuations in tune with orbital cycles are proposed as driving mechanisms. [ABSTRACT FROM AUTHOR]

Foreland contraction and hinterland extension in the Southern Apennines orogen of Italy produced a complex spatial and temporal pattern of vertical and horizontal displacement. Remarkably, Late Miocene to mid-Pleistocene foreland migration of the contractional front at∼16 mm yr−1 was not accompanied by uplift and the frontal thrust belt remained at or below sea level. Only following a mid-Pleistocene reduction in horizontal displacement did the frontal thrust belt and foreland begin uplift at∼0.5 mm yr−1, a rate that increased to∼1 mm yr−1 after 125 ka. Although the extensional hinterland experienced net subsidence during formation of the Tyrrhenian basin, an extensional transition zone adjacent to the frontal thrust belt records sustained uplift at∼0.3 mm yr−1. The interaction of preexisting crustal structure and deep tectonic processes resulted in time-integrated displacement rates suggesting steady-state deformation for periods of 106 years. Displacement rate changes were abrupt and occurred over intervals of 105 years or less.Terra Nova, 00, 1–6, 2005 [ABSTRACT FROM AUTHOR]

Abstract: We describe the following Sieblosiidae: an unamed “gen. and sp. A” from the Miocene of Italy, Miostenolestes zherikhini nov. gen., nov. sp., Paraoligolestes stavropolensis nov. sp., Stenolestes fasciata nov. sp. (all from the Miocene of North Caucasus), Stenolestes (?) adygeianensis nov. sp. (Oligocene of North Caucasus), and Stenolestes cerestensis nov. sp. (Oligocene of France). The genus Sieblosia Handlirsch, 1906 is restored. A new phylogenetic analysis of the Sieblosiidae is proposed. The two taxa “gen. and sp. A” and Oligolestes fall in most inclusive positions in the same clade with the Sieblosiidae. Within the Sieblosiidae sensu stricto, the two clades (Paraoligolestes + (Parastenolestes + Stenolestes)) and (Parastenolestes + Stenolestes) are the best supported. The family Sieblosiidae seems to be restricted to the Oligocene–Miocene of Europe. [Copyright &y& Elsevier]

The Casaglia Monte della Colonna (CMC) body, from the middle Miocene Marnoso-arenacea Formation of the Northern Apennines, covering more than 350 square kilometers, provides a rare opportunity to study the geometry and the internal deformation of a large, basin-wide submarine landslide. Although the head zone of the landslide has not been preserved, the body has a transitional zone, a contractional ramp cutting off more than 200 meters of the footwall stratigraphic succession, and a very wide lobe spilling over onto the adjoining basin plain deposits. The extent of the body, the depth of the ramp cut-off and the widening of the lobe are comparable with the largest present-day submarine landslides, not often observed in fossil examples. Internal deformation structures are distributed differently in the ramp and lobe zones. The ramp zone has antiformal stacking of duplexes and steeply inclined folds. The lobe has a well-defined strain partition: the upper part of the body is affected by extensional structures such as listric normal faults and extensional duplexes; the lower part is deformed by recumbent folds, boudinage and stacking of blocks, which are compatible with flow-induced, heterogeneous simple shear. This distribution is consistent with a kinematic model of extrusion-spreading, implying rear compression in the ramp zone with thickening and shortening of the body, and spreading in the lobe with thinning and stretching. The localized buckling present in the distal part of the lobe may be related to the onset of lateral confinement, due to local topographic features of the basin plain (synsedimentary intrabasinal high). The various degrees and styles of stratal disruption in the mass wasting body depend on the different combination of progressive simple shear, layer-parallel extension and shortening. Different structural associations occur in well-defined parts of the body due to kinematics of emplacement (spreading, flow and buckling). These associations may be diagnostic of gravitational mass wasting processes rather than shallow-level tectonic deformation. [ABSTRACT FROM AUTHOR]

Four small areas of Messinian (Upper Miocene) age gypsum, outcropping in western Sicily, are described. Messinian age evaporites are found in Sicily over a 1000-km2 area. Here, gypsum outcrops extensively as a consequence of soil erosion induced by human impact. Geomorphological maps show how the rocky surfaces are characterized by a wide range of forms. There are large, medium, small, and microsized forms, which can be identified as belonging to different morphotypes. The morphotypes can be classified into two main categories: those that originated by solution and those that originated through recrystallisation.Four areas, illustrated by geomorphological maps, were specifically chosen to describe a type of medium-sized form: dome-like hills. These medium-sized forms are covered by a mosaic of smaller forms, related to both the previous categories: different types of karren and of “expansion” forms. The types of karren can be explained as the results of the solution process under different hydro-dynamical behaviour; the dome-like hills and other related “expansion” forms are more difficult to understand. These “expansion” forms can be explained by the same process that leads to the development of gypsum tumuli. The outcrops of gypsum lacking soil cover and influenced by alternating seasonal water conditions of surplus and deficit are affected by both solution and recrystallisation processes. During the wet season, the water soaks into the rocky mass, filling all the fissures and pores of the outer rocky layer from a few centimetres to some metres below the surface. During the dry season, there is a capillary upward motion of the water solution. Near the surface, gypsum precipitates from the oversaturated solution, increasing the crystal size or forming new crystals. In this way, during the dry season, there is a pressure increase in the outer gypsum layers, which is responsible for the development of a “gypsum weathering crust” and characterised by many different forms such as gypsum tumuli, pressure ridges, pressure humps, and other related small forms. The crust may also lead to the development of mega-tumuli and dome-like hills. From the morphostructural point of view, the dome-like hills do not seem to be controlled by the strike, dip, or fissuring of the gypsum beds. Their evolution seems to be linked to the fact that on most of the dome surfaces, the weathering crust is evolving through a nearly isotropic field of stresses, resulting in volume increase in the outer gypsum layer. [Copyright &y& Elsevier]

ABSTRACT In the foothills of the Northern Apennines mud volcanoes are locally aligned along active normal faults, which allow surface leakage of fluids derived from deep sources (>3–6 km). The chemical and isotopic analysis of the fluids of a mud volcano, coupled with the reconstruction of its geological setting, allowed an investigation of the processes of migration and fluid flow. The fault system associated with the Regnano mud volcano drains a deep Miocene reservoir (foredeep marine deposits), which supplies formation water and thermogenic methane that has migrated from underlying Mesozoic carbonates. The muds from the volcano contain late Eocene microfossils and are extruded only during paroxysmal events. They have a shallower origin (about 1 km) from the base of Tertiary marine deposits deposited upon the upper tectonic nappe of the chain (Ligurian unit). This case study suggests that normal faults are very effective in controlling surface emissions. [ABSTRACT FROM AUTHOR]

The Borbera Valley (northwestern Italy) is located in a complex geological area where the linkage between Alps and Apennines occurs. In this area the Antola Unit (Late Cretaceous–Palaeocene) is unconformably overlain by the Upper Eocene–Miocene succession of the Tertiary Piedmont Basin. The structural analysis indicates the occurrence of a folding phase of Late Oligocene–Early Miocene age, characterised by recumbent F2 folds. These folds are superposed onto D1 structures related to an early folding phase of Middle Eocene, affecting only the Antola Unit. The occurrence of map-scale D2 folding phase structures that affect the Tertiary Piedmont Basin succession suggests that the linkage area between Alps and Apennines was reactivated during the Late Oligocene–Early Miocene. To cite this article: M. Marroni et al., C. R. Geoscience 334 (2002) 565–572. [Copyright &y& Elsevier]

Investigates the Miocene chemoherms from the northern Apennines, Italy. Definition of field and compositional criteria for the recognition of fossil chemoherms; Relation of breciated structures associated with chemoherms to diapirism of overpressured pelitic sediments.

Discusses seismotectonic zoning of the Miocene time to contractional and extensional deformations within east-central Italy. Pattern and orientation of deformation and stress fields; Basement-involved tectonics with multiple detachment system; Tectonic control of crustal seismicity; Domains of sismotectonic zoning; Genesis of seismic deformations.