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Stefano Gori Biagio Giaccio Fabrizio Galadini Emanuela Falcucci Paolo Messina Andrea Sposato Francesco Dramis 《International Journal of Earth Sciences》2011,100(1):157-171
In the present work we analyse one of the active normal faults affecting the central Apennines, i.e. the Mt. Morrone normal
fault system. This tectonic structure, which comprises two parallel, NW-SE trending fault segments, is considered as potentially
responsible for earthquakes of magnitude ≥ 6.5 and its last activation probably occurred during the second century AD. Structural
observations performed along the fault planes have allowed to define the mainly normal kinematics of the tectonic structure,
fitting an approximately N 20° trending extensional deformation. Geological and geomorphological investigations performed
along the whole Mt. Morrone south-western slopes permitted us to identify the displacement of alluvial fans, attributed to
Middle and Late Pleistocene by means of tephro-stratigraphic analyses and geomorphological correlations with dated lacustrine
sequences, along the western fault branch. This allowed to evaluate in 0.4 ± 0.07 mm/year the slip rate of this segment. On
the other hand, the lack of synchronous landforms and/or deposits that can be correlated across the eastern fault segment
prevented the definition of the slip rate related to this fault branch. Nevertheless, basing on a critical review of the available
literature dealing with normal fault systems evolution, we hypothesised a total slip rate of the fault system in the range
of 0.4 ± 0.07 to 0.8 ± 0.09 mm/year. Moreover, basing on the length at surface of the Mt. Morrone fault system (i.e. 22–23 km)
we estimated the maximum expected magnitude of an earthquake that might originate along this tectonic structure in the order
of 6.6–6.7. 相似文献
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Emanuela De Marco Evdokia Tema Philippe Lanos Despina Kondopoulou 《Studia Geophysica et Geodaetica》2014,58(1):121-147
We present an updated compilation of Greek directional archaeomagnetic data for the last 4.5 millennia. The data set comprises 89 directions from archaeological artefacts and volcanic rocks. Most of the data come from the Late Bronze Age (1700-1400 BC) that is the flourishing period of the Minoan civilization in Crete, while parts of the classical (480-323 BC), Hellenistic (323-31 BC) and Roman (146 BC-330 AD) periods are also well covered. The dataset has been analysed using the Bayesian approach for curve building and a directional secular variation (SV) curve for Greece is proposed. Comparisons with regional and global model predictions show a general agreement even though some discrepancies are observed for some time intervals. The new curves together with the previously published intensity SV curve for Greece, also using the Bayesian approach, form a homogeneous set and enrich our knowledge of the full geomagnetic field vector variation in Greece during the last millennia. 相似文献
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Irene Zembo Laura Panzeri Anna Galli Riccardo Bersezio Marco Martini Emanuela Sibilia 《Quaternary Research》2009,72(3):431-442
Optically Stimulated Luminescence (OSL) enables the chronology of the late Pleistocene evolution for the Val d'Agri intermontane basin of Southern Apennines to be defined in the frame of Mediterranean geodynamic and climate changes. Quartz sand from braided floodplain and alluvial fan depositional systems was analyzed using the coarse-grained, single-aliquot regenerative-dose (SAR) technique. The obtained optical ages are mostly consistent with other assessments (radiocarbon, tephrochronology) and stratigraphic constraints. OSL allows for the dating to 56–43 ka of an asymmetric subsidence stage that forced alluvial fan progradation, filling of a former lacustrine area, and development of an axial alluvial plain. A short period of Mediterranean-type pedogenesis, recorded at the top of the prograding-aggrading fans (OSL age bracket 43–32 ka), corresponds with MIS 3. During the subsequent stage of decline of vegetation cover, possibly corresponding to MIS 2, the latest progradation of alluvial fans occurred. The subsequent uplift and breakthrough of the basin threshold during the latest Pleistocene and Holocene induced entrenchment of the drainage network. The results presented here provide an example of the usefulness of OSL dating in intermontane continental settings where other geochronological constraints are scarce. 相似文献
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The Mediterranean Sea constitutes a unique basin from an historical and archaeological point of view, as it has been a privileged way of communication for thousands of years for the people that dwelled on its shores. Their passage has left many traces on the seabeds in the areas where the ancient commercial routes passed, and remains of structures where moorings, havens or dwellings existed. Some of these structures, nowadays submerged, offer interesting indications aiding the reconstruction of the ancient coastlines. This contribution aims to examine recent work in coastal geo-archaeology, targeting both (1) gathering and discussion of the data, particularly those pertaining to the Italian coasts; and (2) commentary on the methodological debate and verification of the possibility of a protocol that may contain unequivocal referring elements.To investigate the archaeological evidence currently underwater because of the relative sea level variations (harbour infrastructures, fishponds, villae maritimae, caves – nymphaei, private or public buildings or town quarters, pre- and protohistorical villages, quarries, caves, etc.), a clear and more coherent methodological assumption may be needed. The archaeological interpretation must initially establish the maritime and/or harbour nature and vocation of the site, determine its typology and specific usage, analyze the elements of its building techniques (that reveal themselves as meaningful markers of height or depth at the time of building) and its “functional” elements (the measure of the emerged part with respect to the average sea level), and point out the time of construction, its chronological range of usage/frequentation, the dynamics of its abandonment/destruction/obliteration.The evaluation of both the height and functional depth to the mean sea level depends on the typology of the archaeological evidence, its use and the local tide amplitudes. The surface of a pier surely has a functional elevation different from that of a haulage area or a platea or a pavement. 相似文献
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Alicia Fantasia Karl B. Fllmi Thierry Adatte Jorge E. Spangenberg Emanuela Mattioli 《Sedimentology》2019,66(1):262-284
A sedimentological, biostratigraphical and geochemical (stable isotopes and Rock‐Eval parameters) analysis was performed on four Swiss successions, in order to examine the expression of the Toarcian Oceanic Anoxic Event along a north–south transect, from the Jura through the Alpine Tethys (Sub‐Briançonnais and Lombardian basins). The locations were selected to represent a range of palaeoceanographic positions from an epicontinental sea to a more open marine setting. The Toarcian Oceanic Anoxic Event was recognized by the presence of the characteristic negative carbon‐isotope excursion in carbonate (ca 2 to 4‰) and organic matter (ca 4 to 5‰) at the base of the falciferum ammonite Zone (NJT6 nannofossil Zone). The sedimentary expression of the Toarcian Oceanic Anoxic Event varies along the transect from laminated mudstone rich in total organic carbon (≤11 wt.%) in the Jura, to thin‐bedded marl (≤5 wt.% total organic carbon) in the Sub‐Briançonnais Basin and to hemipelagic reddish marly limestone (total organic carbon <0·05 wt.%) in equivalent levels from the Lombardian Basin. The carbon‐isotope excursion is thus independent of facies and palaeoceanographic position. The low nannofossil abundance and the peak in Calyculaceae in the Jura and the Sub‐Briançonnais Basin indicate low salinity surface waters and stratified water masses in general. Sedimentological observations (for example, obliquely‐bedded laminae and homogeneous mud layers containing rip‐up clasts) indicate the presence of dynamic conditions, suggesting that water mass stratification was episodically disrupted during the Toarcian Oceanic Anoxic Event. The proposed correlation highlights a stratigraphic gap and/or condensed interval between the Pliensbachian–Toarcian boundary and the Toarcian Oceanic Anoxic Event interval (most of the tenuicostatum ammonite Zone is missing), which is also observed in coeval European sections and points to the influence of sea‐level change and current dynamics. This transect shows that the sedimentary expression of the Toarcian Oceanic Anoxic Event is not uniform across the Alpine Tethys, supporting the importance of local conditions in determining how this event is recorded across different palaeoceanographic settings. 相似文献
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Summary Climatic scenario models forecast an increase of the air temperature in the next century of 1.5–3.5 °C, because of the anthropogenic enhancement of the concentration greenhouse gases in the atmosphere. The analysis of the trend of long-lasting data series of climatic parameters seems to support such a prediction: indeed due to the increase of greenhouse gases in the atmosphere, a climate modification could be already ongoing. Several papers have been published dealing with the global scale climate, this paper, however, deals with an investigation on the regional scale, referring specifically to the Central-Western Mediterranean basin. We are concerned with the parameters which are more affected by climate changes, such as pressure, temperature and precipitation. The analysis carried out indicates that in the Central-Western Mediterranean basin the climate is evolving in a consistent way; we have found: i) an increase of air pressure at the surface and at the upper levels; ii) a reduction in cloudiness and precipitation amount; iii) an increase by about 1 °C in surface air temperature during the period 1860–1995 and in more recent years a rise of the freezing level and of the tropopause; iv) a reduction of strong cyclogenetic events and an increase of heat waves. These results, although compatible with the scenarios predicted, do not allow a final conclusion to be drawn concerning a man-made influence on climate change in the basin.With 13 Figures 相似文献
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One of the basic problems in the prehistoric studies of the Trieste Karst (northeastern Italy) is that of understanding the use of the numerous caves, which represent the only sites known from Palaeolithic to Middle Bronze Age. Recent sedimentological and soil micromorphological analyses add new data to the traditional archaeological ones. In our opinion, the data should be approached from other than an exclusively chronotypological point of view. The inferences of the data indicate that certain areas of four caves were used for stabling animals, and that this model of site use may be extended to most of the Karst cave sites for the period from the Neolithic to Early Bronze Age. © 2000 John Wiley & Sons, Inc. 相似文献
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Emanuela Ceccaroni Gabriele Ameri Antonio Augusto Gómez Capera Fabrizio Galadini 《Natural Hazards》2009,50(2):335-359
The 2nd century AD earthquake in central Italy is only known by an epigraph that mentions restorations to a damaged weighing-house
at the ancient locality of Pagus Interpromium. The available seismic catalogues report this event with the conventional date of 101 AD, a magnitude M
aw of 6.3, and an epicentral location at the village of San Valentino in Abruzzo Citeriore, in the province of Pescara. In order
to improve the knowledge of the damage pattern, we gathered all the archaeological data collected during modern excavations
at sites located in the area, which were presumably struck by the earthquake. This information is mainly represented by (1)
stratigraphic units due to the sudden collapse of buildings over still frequented floors; (2) stratigraphic units demonstrating
restoration or re-building of edifices; (3) stratigraphic units formed as the result of the abandonment of sites or of their
lack of frequentation for decades or centuries. Only stratigraphic evidence consistent with an earthquake occurrence during
the 2nd century AD has been considered. The most recent archaeological material found in a collapsed unit is a coin of Antoninus
Pius, dated at 147–148 AD. This may represent a post quem date very close to the occurrence of the earthquake. The gathered information, plus the stratigraphic data that excluded
the earthquake occurrence at some sites, has allowed us to roughly delineate an area of possible damage, including the Sulmona
Plain and surrounding areas. Comparisons between the possible 2nd century damage distribution and (i) the damage patterns
of more recent historical events that have struck the investigated area, (ii) the distribution of virtual intensities obtained
by simulating an earthquake having an epicenter in the Sulmona Plain and applying an intensity attenuation relationship and
(iii) a shaking scenario obtained by modelling the activation of the major active fault of the Sulmona Plain area (the Mt.
Morrone fault) have revealed consistency between the ancient earthquake and the activation of this fault. Since no other historical
events can be attributed to this active fault, we conclude that the time that has elapsed since the last fault activation
should be in the order of 1,850 years, i.e. a time span that is very close to the recurrence interval of Apennine seismogenic
sources. Moreover, considering the fault length, the causative source may be responsible for earthquakes with M up to 6.6–6.7. The comparison between the presumed 2nd century damage and the shaking scenario suggests that the magnitude
mentioned is consistent with the presumed effects of the ancient earthquake. Finally, considering that Sulmona (the most important
town in the region investigated) is located in the middle of the Mt. Morrone fault hanging wall, we consider it as the probable
epicentral area. Therefore, to summarise the information on the 2nd century AD earthquake, we can conclude that (i) it occurred
shortly after 147–148 AD; (ii) a magnitude M
w 6.6–6.7 can be attributed to it and (iii) the probable macroseismic epicentral area was Sulmona. 相似文献