1,721,011 research outputs found
Le lagune nel mondo antico. Introduzione alle dinamiche insediative, infrastrutture e ambiente
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Geophysical surveys for lagoon archeology: Possibilities and prospects|INDAGINI GEOFISICHE PER L’ARCHEOLOGIA LAGUNARE: POSSIBILITÀ E PROSPETTIVE*
No full textGeophysical prospections have been part of the survey tools available for archaeological research for decades. Today, most of the survey techniques known in the geological field are also applied in the archaeological research by their non-invasive-ness and ability to provide essential information on the loca-tion and extent of buried structures of interest, even over vast areas. The fields of application of geophysical survey techniques for archaeological purposes range from land (e.g. rural, urban or coastal contexts) to semi-and submerged environments, which include fresh, salt or brackish water and humid or shal-low water areas. The latter is part of the lagoon environment, the complexity of which limits and sometimes precludes the use of specific techniques generally used on dry land and requires the adoption of expedients during the data acquisition phase, compared to other ordinary contexts. Therefore, we here describe the main prospecting methodologies applied to date for archaeological research in the lagoon areas, pro-viding a general, albeit not exhaustive, picture of the potential and limits in this specific field of application through some references to the literature and a few case studies, referring to the specific literature on the subject for any necessary and more detailed information
Indagini nell'area di S. Maria in Padovetere in Valle Pega
No full textIndagini geoarcheologiche attraverso il telerilevamento e l'esecuzione di carotaggi manuali e datazioni al radiocarbonio hanno permesso di ricostruire la stratigrafia e l'andamento planimetrico del canale artificiale di Motta della Girata (Valle Pega, Comacchio), collocando il suo periodo di attività tra il VII e il IX secolo d.C
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Strutture arginali antiche e paesaggio lagunare presso l'isola di Sant'Erasmo, laguna di Venezia.
No full textNell’ambito di una campagna di indagini archeologiche subacquee nei bassifondi a nordovest dell’isola di Sant’Erasmo, nella laguna nord di Venezia, sono stati identificati diversi siti riconducibili a strutture arginali antiche, in vari casi a quelle note localmente come ‘argini-strada’, giacenti
sotto potenti strati di sedimento prevalentemente limoso. L’attribuzione a questa tipologia deriva dall’incrocio dei dati raccolti nelle due fasi delle indagini: il grande sviluppo longitudinale e la larghezza più o meno costante delle anomalie rilevate con la sonda metallica manuale e la natura delle stesse, costituita da pali lignei e accumuli di materiali di reimpiego, fondamentalmente laterizi e anfore, messi in luce con l’apertura di piccoli saggi di scavo. Si rileva una costante discrepanza tra la datazione dei materiali, tutti riferibili ad epoca romana, e quella dei pali lignei, che riconduce ad epoca tardo-antica ed altomedievale. Le evidenze riscontrate contribuiscono a definire il paesaggio lagunare antico, in una zona prossima al litorale.Within a campaign of underwater archaeological investigations in the shallows to the north-west of the island of Sant'Erasmo, in the northern lagoon of Venice, several sites have been identified that can be traced back to ancient embankment structures, in several cases to those known locally as ‘road-embankments’, lying under very thick layers of predominantly silty sediment. The attribution to this typology derives from merging the data collected in the two phases of the investigations: the large longitudinal development and more or less constant width of the findings detected with the hand-held metal probe and the nature of the same finds, consisting of wooden piles and accumulations of reused materials, basically bricks and amphorae, brought to light with the opening of small excavation tests. There is a constant divergence between the dating of the materials, all referable to the Roman period, and that of the wooden piles, which leads back to the late antique and early medieval periods. The evidence found contributes to defining the ancient lagoon landscape in an area close to the littoral zone
‘Well-cisterns’ of Roman period indicate navigation routes and landscape modifications in the lagoon of Venice and along the north-eastern Adriatic coast.
Full text linkUnderwater investigations in the lagoon of Venice have permitted to interpret a structure made of bricks of Roman period as a partially preserved well-cistern . This structure is indeed very similar to another, better-preserved cistern excavated in the same area. The analysis of mortars, the evaluation of the depth of the structure base in respect to relative sea level, and the absence of foundation poles in the underlying soft lagoon mud support such interpretation. Our results confute the previous interpretation of this structure as a tower. A comparison with other poorly-studied Roman structures of the same type located along the North Adriatic littoral, suggests that they were probably used to supply the ships of fresh water. In the Middle Age, similar artefacts were used in the islands of the lagoon for the sustenance of the citizens and became a characteristic of the small squares (campi) of Venice. The analysis of the Roman cisterns of Canale San Felice tidal channel and adjoining pier confirm the importance of investigating these infrastructures in order to gain a better understanding of inland navigation routes along the upper Adriatic lagoons
Alluvial fans and megafans along the southern side of the Alps
No full textThe foreland basin of the southern European Alps is characterized by large fan-shaped alluvial systems fed by the
main montane valleys and these depositional systems present an extent of 300–3000 km2, with a length of
30–70 km.Most of themare megafans, characterized by evident longitudinal differentiation inwhich steep piedmont
sector consists of amalgamated gravels, while the distal portion has a gradient b2‰ and is dominated by
fine sediments. The major depositional phase occurred between 26 and 19 kyr cal BP during the Last Glacial
Maximum (LGM) marine lowstand, when the Alpine glaciers reached the plain and fed the related fluvioglacial
systems. The easternmost megafans also partly extended on the Adriatic shelf whereas, west from Garda Lake,
their downstream development was limited by the Po River plain. The thickness of LGM alluvial sedimentation
ranges between 30 and 15 m and pinches out about 25 km off the present coast. Soon after ice decay,
after 19–17 kyr cal BP, sediment delivery from Alpine catchments to the plain dramatically decreased
and in the central Alps large intramontane lakes formed, trapping almost all the bedload. Thus, the ratio between
sediment andwater discharge dramatically decreased and an erosive phase affected the LGMmegafans and fans,
leading the rivers to entrench for tens ofmeters. The funneling effect created by the fluvial incisions allowed the
gravels to arrive tens of kilometers further downstream than in the LGM. In the Venetian–Friulian megafans a
single valley formed in the piedmont sector, while 2–5 incised valleys developed in the distal sector. These latter
valleys have been almost completely filled by a depositional lobe formed in the last 8 kyr, partly triggered by Holocene
sea-level rise. The Alpine tributaries of the river Po still flow along a single incised valley from their
megafan apex to the junction with the Po and they have not yet been affected by sea-level influence
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