141 research outputs found

    Non-volcanic CO2 and CH4 degassing in an actively extending orogen, southern Apennines, Italy

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    The southern Apennines fold and thrust belt has been undergoing post-orogenic extension since ca. 700 kyr. Crustal extension controls active tectonics and seismogenesis in the mountain chain [1], with seismicity being characterized by low to moderate magnitude events punctuated by strong earthquakes [2]. Effective decoupling between deep and shallow structural levels is related to the strong rheological contrast produced by a fluid-saturated, clay-rich mélange zone interposed between buried autochthonous carbonates – continuous with those exposed in the Apulian foreland – and the allochthonous units. This mélange zone also acts as a seal preventing the migration of deep-seated aqueous fluids – as well as oil in the Basilicata region, which hosts the largest Europe’s onshore oil fields – towards the surface. On the other hand, the mountain belt is characterized by substantial gas flow, recorded as both distributed soil gas emissions and vigorous gas vents, associated with active faults at the surface. We measured a CO2 flux up to 34000 g/m-2 per day at a gas vent, as well as large amounts of He (up to 52 ppm), Rn (up to 228 kBq/m3) and CH4 (up to 5000 ppm). Overpressured CO2, which has been proposed as triggering normal fault earthquakes in the Apennines, has been interpreted as mostly of mantle origin. However, our new results from isotope analyses carried out on the carbon contained in both CO2 and CH4 indicate a dominant thermogenic origin for these gases, probably associated with the emplacement of magmatic sills within the lower section of the thick carbonate platform succession occurring at the base of the sedimentary cover in the southern Apennines. Our results bear major implication concerning the postulated occurrence of crustal faults allowing fluids to migrate directly from mantle depths to the surface

    Quaternary deformation in SE Sicily: Insights into the life and cycles of forebulge fault systems

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    Integrated geological, geomorphological, and differential interferometry synthetic aperture radar (DInSAR) data are used to constrain the timing and modes of activity of Quaternary fault systems in the Hyblean Plateau. This area, which represents a unique natural laboratory for studying surface deformation in relation to deep slab dynamics, has grown since middle Miocene times as a doubly plunging forebulge associated with slab rollback during NW-directed subduction. Bimodal extension has produced two mutually orthogonal normal fault systems. The detailed stratigraphic record provided by synrift sediments and postrift marine terraces allowed us to define the timing of activity of an early Pleistocene, flexure-related fault system, thus constraining the duration of a typical foreland extensional tectonic event to ~1.5 m.y. Subsequent late Quaternary to present deformation was dominated by strike-slip faulting associated with NW-oriented horizontal compression. During this latest stage, regional uplift progressively increased toward the thrust front to the NW and was accompanied by differential uplift accommodated by dip-slip components of motion along active NNW-trending faults. The general active tectonic setting of the study area, characterized by NW-oriented horizontal compression consistent with major plate convergence, and the regional uplift pattern can both be explained within the framework of intraplate shortening and foreland rebound following complete slab detachment, a major geodynamic event interpreted to have taken place at ca. 0.7 Ma in southern Italy

    Generation and characterization of a human single-chain fragment variable (scFv) antibody against cytosine deaminase from Yeast

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    <p>Abstract</p> <p>Background</p> <p>The ability of cytosine deaminase (CD) to convert the antifungal agent 5-fluorocytosine (5-FC) into one of the most potent and largely used anticancer compound such as 5-fluorouracil (5-FU) raised considerable interest in this enzyme to model gene or antibody – directed enzyme-prodrug therapy (GDEPT/ADEPT) aiming to improve the therapeutic ratio (benefit versus toxic side-effects) of cancer chemotherapy. The selection and characterization of a human monoclonal antibody in single chain fragment (scFv) format represents a powerful reagent to allow in <it>in vitro </it>and <it>in vivo </it>detection of CD expression in GDEPT/ADEPT studies.</p> <p>Results</p> <p>An enzymatic active recombinant CD from yeast (yCD) was expressed in E. coli system and used as antigen for biopanning approach of the large semi-synthetic ETH-2 antibody phage library. Several scFvs were isolated and specificity towards yCD was confirmed by Western blot and ELISA. Further, biochemical and functional investigations demonstrated that the binding of specific scFv with yCD did not interfere with the activity of the enzyme in converting 5-FC into 5-FU.</p> <p>Conclusion</p> <p>The construction of libraries of recombinant antibody fragments that are displayed on the surface of filamentous phage, and the selection of phage antibodies against target antigens, have become an important biotechnological tool in generating new monoclonal antibodies for research and clinical applications. The scFvH5 generated by this method is the first human antibody which is able to detect yCD in routinary laboratory techniques without interfering with its enzymatic function.</p

    Geomorphology of Naples and the Campi Flegrei: human and natural landscapes in a restless land

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    Naples and its surroundings are a very young landscape, originated from 40 ka in response to strong and explosive volcanic processes, which created the Campi Flegrei, one of the largest volcanic fields of the world. Despite the repeated and continuous volcanic activity, this territory was selected for human settlements since Neolithic times and hosted some of the most important Greek and Roman towns in the Mediterranean area (e.g., Cuma, Parthenope, Neapolis, Baia and Puteoli). Geoarcheological data and historical chronicles testify to human coexistence with eruptions, bradyseismic ground motions, coastline changes, floods and landslides. With the aim of describing the geomorphological evolution of this area to a wide audience, including also non-experts, we constructed a synthetic geomorphological map of the area and sketches that synthesise the main stages of the geomorphological evolution of the historical centre of Naples and the coastal belt of the Gulf of Pozzuoli during the last millennia

    The human antibody fragment DIATHIS1 specific for CEACAM1 enhances natural killer cell cytotoxicity against melanoma cell lines in vitro

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    Several lines of evidence show that de novo expression of carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is strongly associated with reduced disease-free survival of patients affected by metastatic melanoma. Previously published investigations report that homophilic interactions between CEACAM1 expressed on natural killer (NK) cells and tumors inhibit the NK cell-mediated killing independently of major histocompatibility complex class I recognition. This biological property can be physiologically relevant in metastatic melanoma because of the increased CEACAM1 expression observed on NK cells from some patients. Moreover, this inhibitory mechanism in many cases might hinder the efficacy of immunotherapeutic treatments of CEACAM1 malignancies because of tumor evasion by activated effector cells. In the present study, we designed an in vitro experimental model showing that the human single-chain variable fragment (scFv) DIATHIS1 specific for CEACAM1 is able to enhance the lytic machinery of NK cells against CEACAM1 melanoma cells. The coincubation of the scFv DIATHIS1 with CEACAM1 melanoma cells and NK-92 cell line significantly increases the cell-mediated cytotoxicity. Moreover, pretreatment of melanoma cells with scFv DIATHIS1 promotes the activation and the degranulation capacity of in vitro-expanded NK cells from healthy donors. It is interesting to note that the melanoma cell line MelC and the primary melanoma cells STA that respond better to DIATHIS1 treatment, express higher relative levels of CEACAM1-3L and CEACAM1-3S splice variants isoforms compared with Mel501 cells that are less responsive to DIATHIS1-induced NK cell-mediated cytotoxicity. Taken together, our results suggest that the fully human antibody fragment DIATHIS1 originated by biopanning approach from a phage antibody library may represent a relevant biotechnological platform to design and develop completely human antimelanoma therapeutics of biological origin

    Generation of human antibody fragments recognizing distinct epitopes of the nucleocapsid (N) SARS-CoV protein using a phage display approach

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    BACKGROUND: Severe acute respiratory syndrome (SARS)-CoV is a newly emerging virus that causes SARS with high mortality rate in infected people. Successful control of the global SARS epidemic will require rapid and sensitive diagnostic tests to monitor its spread, as well as, the development of vaccines and new antiviral compounds including neutralizing antibodies that effectively prevent or treat this disease. METHODS: The human synthetic single-chain fragment variable (scFv) ETH-2 phage antibody library was used for the isolation of scFvs against the nucleocapsid (N) protein of SARS-CoV using a bio panning-based strategy. The selected scFvs were characterized under genetics-molecular aspects and for SARS-CoV N protein detection in ELISA, western blotting and immunocytochemistry. RESULTS: Human scFv antibodies to N protein of SARS-CoV can be easily isolated by selecting the ETH-2 phage library on immunotubes coated with antigen. These in vitro selected human scFvs specifically recognize in ELISA and western blotting studies distinct epitopes in N protein domains and detect in immunohistochemistry investigations SARS-CoV particles in infected Vero cells. CONCLUSION: The human scFv antibodies isolated and described in this study represent useful reagents for rapid detection of N SARS-CoV protein and SARS virus particles in infected target cells

    Impact of safety-related dose reductions or discontinuations on sustained virologic response in HCV-infected patients: Results from the GUARD-C Cohort

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    BACKGROUND: Despite the introduction of direct-acting antiviral agents for chronic hepatitis C virus (HCV) infection, peginterferon alfa/ribavirin remains relevant in many resource-constrained settings. The non-randomized GUARD-C cohort investigated baseline predictors of safety-related dose reductions or discontinuations (sr-RD) and their impact on sustained virologic response (SVR) in patients receiving peginterferon alfa/ribavirin in routine practice. METHODS: A total of 3181 HCV-mono-infected treatment-naive patients were assigned to 24 or 48 weeks of peginterferon alfa/ribavirin by their physician. Patients were categorized by time-to-first sr-RD (Week 4/12). Detailed analyses of the impact of sr-RD on SVR24 (HCV RNA <50 IU/mL) were conducted in 951 Caucasian, noncirrhotic genotype (G)1 patients assigned to peginterferon alfa-2a/ribavirin for 48 weeks. The probability of SVR24 was identified by a baseline scoring system (range: 0-9 points) on which scores of 5 to 9 and <5 represent high and low probability of SVR24, respectively. RESULTS: SVR24 rates were 46.1% (754/1634), 77.1% (279/362), 68.0% (514/756), and 51.3% (203/396), respectively, in G1, 2, 3, and 4 patients. Overall, 16.9% and 21.8% patients experienced 651 sr-RD for peginterferon alfa and ribavirin, respectively. Among Caucasian noncirrhotic G1 patients: female sex, lower body mass index, pre-existing cardiovascular/pulmonary disease, and low hematological indices were prognostic factors of sr-RD; SVR24 was lower in patients with 651 vs. no sr-RD by Week 4 (37.9% vs. 54.4%; P = 0.0046) and Week 12 (41.7% vs. 55.3%; P = 0.0016); sr-RD by Week 4/12 significantly reduced SVR24 in patients with scores <5 but not 655. CONCLUSIONS: In conclusion, sr-RD to peginterferon alfa-2a/ribavirin significantly impacts on SVR24 rates in treatment-naive G1 noncirrhotic Caucasian patients. Baseline characteristics can help select patients with a high probability of SVR24 and a low probability of sr-RD with peginterferon alfa-2a/ribavirin

    Long-term morphotectonic evolution of the southern Apennines

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    ABSTRACT The main goal of this work is the study of the morphological and morphometrical features of the Southern Apennines thrust belt – foredeep system, carrying out both a large scale and a small scale analyses of areas of high relevance, with the aim to determine new morphological and morphometrical constraints to the reconstruction of the main morphotectonic events that have interested the chain. This type of research has been based on the idea to compare such data with new thermochronological data that have been produced in many areas of the chain (Aldega et al., 2003; Mazzoli et al., 2006; Mazzoli et al., 2008), which highlighted the role of the exhumation processes in the evolution of the thrust belt. The thermochronological data indicate that the exhumation processes started about 10Ma and they have been active since recent time (in the last million years), resulting contemporary to the main morphogenetic events responsible of the actual morphostructural setting of the chain. The Southern Apennines chain formed has a consequence of the Neogene collision of the African (and in particular, the Adria microplate) and Euroasiatic plates, with the subduction of the Adria microplate beneath the Euroasiatic plate. The morphostructural setting of the Southern Apennines has been determined by its complex tectonic history (with the occurrence of both thrust faults and normal faults) and by the erosional processes that have sculptured the topography, also considering that the landforms are strongly influenced by the rock type too. In the last years the development of new techniques of analysis has provided new constraints useful to the reconstruction of the morphotectonic history of the Southern Apennines. This techniques are based on thermochronological analysis, and in particular on the Apatite Fission Tracks, the Ur-Th-He series, the Vitrinite Reflectance, the Clay Mineralogy and the Fluid Inclusions. These data, that have been extensively produced in the whole chain, have pointed out the attention on tectonic exhumation processes (we mean by rock exhumation a variation of the position of a rock in relation to the air-topograhy interface), which have determined rock uplift of thousands of meters in the last 2-3Ma (Aldega et al., 2003; Mazzoli et al., 2006; Mazzoli et al., 2008). The individuation of so enhanced vertical and horizontal tectonic motions in recent times has expected to have interacted with the processes responsible of the exogenic modelling of the topography, and they have probably played an important role in the morphotectonic evolution of the chain, leaving their signature in the topography. The research has been based on large scale geomorphological and morphometrical techniques of analysis, that have been used with the aim to describe the main morphological and morphometrical features of the chain, to compare the features of the Tyrrhenian, Adriatic and Ionian slopes of the Southern Apennines, and to relate these features with the proposed morphotectonic events. The large scale analysis has been accompanied by the small scale analysis of a selected transect namely the Noce-Sirino-Alpi-Sant’Arcangelo transect. This transect has been chosen because of the particular features that make this area one of the most relevant portion of the chain in order to reconstruct the morphotectonic evolution of the Southern Apennines, and in particular, to investigate the role played by the rock exhumation processes in the evolution of the relief. This transect assumes a high relevance because: - it includes tectonic units which have been exhumed in recent times; - it preserves a stratigraphical and morpho-stratigraphical record which is almost continuous both temporally (from the Middle Pliocene to the whole Quaternary) and spatially (from the Tyrrhenian to the Adriatic coasts); - the topography, in this portion of the Southern Apennines, has been only slightly dismembered by the post-orogenic extensional tectonic, and may be considered resulting by the major geodynamic processes (shortening, thrusting, extension and exhumation). One of the main parameters that can influence the geomorphological and morphometrical features of a determined region is the lithology, or more correctly the bedrock resistance to erosion. In fact, parameters such as the elevation, local relief, steepness, presence of knickpoints are strongly controlled by bedrock erodibility. As a result, the first step in the analysis of the landscape is represented by a clear depiction of the space distribution of the rock types with different erodibility. For the above mentioned reason, a “Map of the Morphostructural Units of the Southern Apennines” has been created. This map is a simplification of the “Geological Map of the Southern Apennines” in scale 1:250000, in fact the 81 formations distinguished in the “Geological Map of the Southern Apennines” have been reduced into the 20 morphostructural units which have been grouped based on the estimation of erodibility of each rock type relative to other rock types. The erodibility degree was basically assigned by the observations of the features (e.g. steepness, degree of development of the upper convexity/basal concavity of hillslopes, average elevation, etc.) associated with the various bedrocks. As regards the Quaternary deposits, these were grouped based on different criteria. Taking into account the main goal of this study, which consists in the reconstruction of the Plio-Quaternary relative/absolute vertical motions of the Southern Apennines, the grouping of the different Quaternary stratigraphical units was based on the depositional environment (marine vs continental), degree of correlation of the different units with the original depositional environment (i.e. whether and to what degree they are displaced/dissected), and tectonic context (e.g. peri-tyrrhenian grabens, foredeep and intramontane basins deposits). The large scale geomorphological analysis of the Southern Apennines has been based on the determination of the following parameters: elevation map and the derived maximum, medium and minimum elevation maps, swath profiles and the derived relief curves, analysis of the river long profiles and the derived parameters (drainage area vs distance, Stream Gradient Index, steepness (ks) and concavity (Q) indexes, slope of the first order channels). This type of analysis enhance a series of particular feature of the Southern Apennines that can be summarized as follows: - the minimum elevation map can be separated in two different sector, respectively located north and south of the hereinafter named “Sele-Ofanto line”: the north sector is characterized by the coincidence of the highest values with the apenninic divide, while the southern sector is characterized by the presence of a wide area with high values in the minimum elevations, which moves from the apenninic divide to the east, involving the foredeep (and the Lavello high) and the Murge-Salento area ; - this data regarding the minimum elevation map is very interesting in particular when compared with the “Map of the Morphostructural Units of the Southern Apennines”: this comparison show that the valleys on the Adriatic flank are higher than the valleys on the Tyrrhenian flank despite the Adriatic flank is characterized by the outcropping of very weak lithologies (external flyschs and Quaternary filling of the foredeep); - the minimum elevation map could be so considered a good representation of the differential uplift at the orogen scale; this fact let the maximum elevation map to play a less relevant role when we want to interpret it in terms of uplift, and it can be more correctly considered as a good representation of the distribution of the tectonic Quaternary lows; - the medium elevation map clearly enhance the presence of the hard carbonatic highs on the Tyrrhenian slope respect to more eroded surrounding areas where weaker lithologies crop out. This means that the Tyrrhenian slope has experienced a more intense erosion, or even that it is experiencing erosion since older times than the Adriatic flank (where the same weak lithologies crop out), and that the amount of eroded rock volumes is higher on the Tyrrhenian flank than on the Adriatic flank. If this two sectors were experiencing erosion since the same time, than we cannot explain why the external flank of the chain is higher than its inner flank despite this two sectors are characterized by the same rock-type; - the analysis of the maximum, medium and minimum elevation maps suggests that the Adriatic flank of the Southern Apennines has experienced more enhanced uplift in recent times than the Tyrrhenian flank; - the Tyrrhenian and the Adriatic flanks of the chain have also other different morphological and morphometrical features, in particular the Tyrrhenian flank becomes steeper than the Adriatic flank as we move to the south, giving the typical asymmetrical feature to the Southern Apennine; - this asymmetrical feature of the chain is clearly showed by the envelop of the minimum elevation line of the five swath profiles, which enhance the presence of a Tyrrhenian steep slope and of an Adriatic gentle slope; - there is an important difference regarding the elevation of the valleys on Tyrrhenian and the Adriatic flanks, with a mean gradient that bring the valleys to reach elevations a.s.l. higher on both the flanks as we move to the south, but in general the valleys on the Tyrrhenian flank are always lower than the valleys on the Adriatica flank: such a difference suggest a more recent uplift on the Adriatic flank than on the Tyrrhenian one; The analysis of the river system shows how there is a spatial variations of the morphological and morphometrical features of the Southern Apennine rivers. If we consider the shape of the river long profiles we notice that the Tyrrhenian rivers have a clear concave-up shape with no important knickpoints, while the Adriatic rivers show a more rectilinear shape and the Ionian rivers show a less evident concave-up shape, in same cases close to the rectilinear, with evident knickpoints along the profiles. The Q (concavity index) values show a difference among the three sectors, with the Tyrrhenian rivers showing the highest value (Q=0.52), the Adriatic rivers showing a lower value (Q=0.45) and with the Ionian rivers showing the lowest value (Q=0.43). This data confirm what we noticed by the analysis of the river long profiles, in particular the Tyrrhenian rivers have a more evident concave-up shape and the Ionian rivers the less evident concave-up shape. The clear concave up shape of the Tyrrhenian rivers can be related to a more enhanced uplift on the Adriatic and Ionian slopes than on the Tyrrhenian slope. If we consider the Ks (steepness index) values, we suggest that in a geological setting such as the Southern Apennines, that is characterized by important lithological variations also in very close areas, the Ks index seems to reflect such variations more than recent rock uplift The geomorphological, morphometrical and sedimentological analysis of the Noce-Sirino-Alpi-Sant’Arcangelo transect allowed the individuation of two low relief landforms which are located on the western sector of the Sant’Arcangelo basin (700-900m a.s.l.) and in the area between the north side of Mt. Sirino, Mt. Raparo and Mt. Alpi (1200-1400m a.s.l.). The lowest surface (700-900m a.s.l.) corresponds to the eroded depositional surface of the Serracorneta Conglomerate, so it is temporally constrained at about 0.6Ma. The morphological relationships among this lower paleosurface and the highest one are not clear, we can anyway affirm that it is recognized in the area north of the Mt. Sirino and it involves both carbonates units than Lagonegro Units, so its modelling took place after the exhumation of the Mt. Sirino ended and so, considering the data we are going to talk about soon, it could temporally constrained in the Middle-Late Lower Pleistocene, and in particular between 1.5-0.6Ma. The field analysis let us to recognize the oldest units of the Qquaternary filling of the Sant’Arcangelo basin that contains clasts of the Lagonegro Units coming from the Mt. Sirino area: this unit is the subsynthem A2a (Benvenuti et al., 2006) which should be not older than 1.5Ma, so this means that at this time the Mt. Sirino was already a morphostructural highs that was experiencing erosion. This data agrees with the thermochronological analysis, which suggested that the rock exhumation of the Mt. Sirino started since 2.5Ma, and it has allowed us to give a lower temporal limit to the formation of the highest paleosurface. The analysis of the “map of the slope of the 1st order channels”, carried out within the Sant’Arcangelo basin, suggests that the area comprised between the Serrapotamo and the Sarmento river shows the highest values: these high slope values could be related to a more enhanced uplift that this area has experienced respect to the rest of the Sant’Arcangelo basin. If we combine this data with the uplift data obtained by the analysis of the marine terraces on the Ionian coast (Amato, 2000), we have that the southwestern portion of the Sant’Arcangelo basin seems to be aligned with the southernmost Ionian coast, that is the portion of the Ionian coast which has experienced a more enhanced uplift: this data could suggest a connection between these two sectors, highlighting the presence of this NW-SE oriented portion of the Southern Apennines that has been strongly uplifted. The analysis of the river terraces inside the Sinni valley has allowed the individuation of 7 orders of river terraces. The highest order, the 7th, doesn’t correspond to a real river terrace but it corresponds with the eroded depositional surface of the Serracorneta Conglomerates, whose age is of about 0.6Ma (Benvenuti et al., 2006). To date the lowest terraces we can try to correlate them with the dated marine terraces on the Ionian coast (Amato, 2000), this analysis let us to propose a late Upper Pleistocene for the 1st order terraces of the Sinni valley Considering the age of the highest river terraces and the actual elevation of the Sinni valley it is also possible to establish an incision rate of about 1mm/yr: the incision rate is always greater or equal to the uplift rate, so we can say that the uplift rate of the Sinni valley since 0.6Ma doesn’t exceed 1mm/yr. This uplift rate agrees with the uplift rate that have been proposed by Amato (2000) for the marine terraces on the Ionian coast, where the author proposed an uplift rate comprised between 0.3-1.6mm/yr. The analysis of the Noce valley river terraces has allowed the grouping of the several mapped fluvial terraces into three main orders: pre-lake, syn-lake and post-lake terraces. There are no absolute date available to date the lake time, so the age of the syn-lake terraces has been obtained using methods of relative chronology, by trying to correlate such terraces with dated marine terraces on the Tyrrhenian coast at the mouth of the Noce river: an Emilian-Sicilian age is proposed for the highest marine terraces at 170m and 140m a.s.l., while a Middle Pleistocene age is proposed for the 80m a.s.l. marine terrace. The oldest marine terraces are extended inside the Noce valley, so it means that at that time the Noce valley was already individuated. In addiction to this we have to consider that, on the basis of morphometrical considerations, such marine terraces are correlable with the river terraces at about 200m a.s.l. individuated in locality Feliceta, inside the Noce valley, and that are referred to the post-lake river terraces. Another important issue is given by the presence of Lagonegro clasts into this marine deposits and, considering that the only area from which these clasts could come from is Mt. Sirino, this data suggests that at the time of the formation of the oldest marine terraces (about 1Ma), Mt. Sirino was already experiencing erosion, so it was very close to the actual morphostructural setting. The combination of the sedimentological data of the SAnt’Arcagenlo basin and the analysis of the Noce river terraces allowed us to affirm that about 1.5-1Ma Mt. Sirino was already a morphological high which was experiencing erosion, so it means that the rock exhumation processes was finished: the comparison of these data with the thermochronological data suggest that in the period between 2.5Ma and 1.5-1Ma Mt. Sirino has experienced an enhanced rock exhumation that has brought it from an initial situation where it was covered by about 4km of rocks (2.5Ma) to a final situation where it outcrops on the Earth surface and it was subject to the exogenic processes (1.5-1Ma). This study has highlighted the importance of the morphotectonic approach in the reconstruction of the tectonic events occurred either at a regional scale or at a local scale. In particular, the numerical analysis of digital topographic data has been very useful to the large scale characterization of the Southern Apennines chain landscape. Furthermore, the integration of data provided by the digital analysis technique (e.g. swath profiles, river long profiles and the derived metrics), with the data obtained through the “classical” geomorphological approach, based on morphostructural and morphostratigraphical analyses, has provided new constraints to the reconstruction of the vertical motions which affected the entire chain during the Quaternary. The main results of this study can be summarized as follows: - long profiles, elevation of the valley bottoms and the minimum elevation map show that the outer portion of the Southern Apennines (Adriatic and Ionian slopes) has been uplifted more recently and with higher rates than its inner side (Tyrrhenian slope). These data agree with data provided by the analysis of the shorelines, marine terraces and coastal deposits observed on the Ionian belt (Amato, 2000) and the Tyrrhenian margin (Romano, 1992; Caiazzo et al., 2006), which indicate that the Ionian flank has experienced larger uplift, since the Middle Pleistocene, than the Tyrrhenian flank; - the Ionian rivers show a very steep long profile when they flow into the Sant’Arcangelo basin. This suggests that the post-orogenic uplift recognized by the marine terraces in the foredeep affected also the outer portion of the chain, involving at least the Sant’Arcangelo area; - by the comparison of the Agri and the Sinni long profile, by the map of the gradient of the first order channel, and by the Ks values (which are higher on the southern portion of the Sant’Arcangelo basin and that decrease moving towards its northern portion) it appears that the uplift in the Sant’Arcangelo area follows a N-S trend. However, further studies are necessary to discern about the reason of such different uplift; - as regards to the Middle Pleistocene to Present uplift trend, the above observations indicate that the uplift increases towards the west, probably reaching the chain axis. Coeval uplift in the Tyrrhenian margin (as estimated by elevation of Middle to Late Pleistocene marine terraces shorelines; Romano, 1992; Caiazzo et al., 2006; Filocamo, 2006) was much lower, not exceeding about 100 m. These evidences suggest that the uplift trend of the outer flank of the chain is not recognizable in the whole orogen. The western boundary of the more rapidly uplifting belt can be tentatively located in correspondence to the deep-seated normal faults that have formed the several Quaternary intramontane basins; - the stronger post-orogenic uplift occurred on the outer side of the chain since the Middle Pleistocene has determined a minor ability of the Adriatic and Ionian rivers (which experienced a continuous downcutting) to compete with the Tyrrhenian rivers. This fact is enhanced by the comparison of the valley bottoms, which are higher for the rivers flowing on the outer flank than for the rivers flowing on the inner flank of the chain. This has probably contributed, together with regressive river erosion due to the extensional tectonics on the Tyrrhenian margin (see sec. 3.5), in the decoupling between the maximum elevation line and the main divide, which is one of the peculiar features of the Southern Apennines chain; - the combination of the field analysis together with the morphological and morphometrical analysis of the Noce-Sirino-Alpi-Sant’Arcangelo transect allowed us to affirm that during the late Lower Pleistocene Mt. Sirino was already a morphological high which was experiencing erosion, so it means that the rock exhumation processes was finished; - this data is confirmed by the analysis of the river terraces of the Noce valley: the lacustrine conditions have been dated (by methods of relative chronology on the basis of the morphological relationships among the fluvial terraces of the Noce valley and dated marine terraces on the Tyrrhenian coast close to the Noce mouth) to the middle Lower Pleistocene, and the recognition of Lagonegro clasts inside the oldest marine deposits (Lower Pleistocene) suggests that at that time there was an active drainage from Mt. Sirino to the south, and so Mt. Sirino was already a morphological high subject to the erosional processes and able to produce debris, and the lake didn’t exist anymore; - in addiction to this, we have to consider that since its exhumation, Mt. Sirino corresponds to the location of the Apennine divide, representing one of the few portion of the Southern Apennines where there is a coincidence between the maximum elevation line and the divide location. This situation is partly recognized also in Monti Picentini area, where the two lines (divide and maximum elevation lines)
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