Multi-resolution morpho-bathymetric survey results at the Pozzuoli–Baia underwater archaeological site (Naples,Italy)

Here we show the results of two morpho-bathymetric surveys carried out on the underwater archaeological area of the Pozzuoli Bay (Naples, Italy). Such area is enclosed in the Campi Flegrei active volcanic complex, where bradyseism and recent volcanic activity strongly influenced the coastline shape over the last 2 Ka. The Digital Elevation Model (DTM) of the seafloor allowed to draw the main archaeological features of the Bay, that also include the military complex of Portus Iulius and the ancient thermal and villa complex of Baianus Lacus. The extraction of archaeological features from DTM was achieved thanks to the use of a GIS-derived tool based on the profile curvature algorithm. Thus, the Villa dei Pisoni (1st Century B.C.) and the thermal complex of Secca delle Fumose were investigated by using ultra-high resolution DTMs, that show the presence of Roman pilae for the protection of coastal buildings and also the inner planimetry of the Villa dei Pisoni complex. The observation of coastal engineering structures give also the opportunity to formulate some hypothesis on the evolution of morphology and of the sedimentary pattern of the area, while depth of archaeological remains allowed a rough computation of the rate of subsidence, resulted to be 2.55 (±0.5) mm/y for the Eastern sector (Pozzuoli) and 2.90 (±0.5) mm/y for the western (Baia).     

The colour of the facades in Siena’s historical centre: I. Glazings (calcium oxalate films s.s.) and other finishes on the stone materials of the Cathedral’s main facade

This paper focuses on the long-debated topic of the so-called calcium oxalate films: their origin and meaning but also their age and original appearance. The restoration of the main facade of the Siena Cathedral provided a unique opportunity to this end, thanks to the possibility of an extensive and detailed sampling and (as rarely happens) a sufficiently accurate historical knowledge of the construction vicissitudes. This work, mainly based on a polarising microscopy study (coupled with X-ray diffraction and SEM-EDS analyses) of over a thousand thin and ultra-thin sections of 400 microsamples, demonstrates that the current relicts of films are the result of alteration and decay of ancient treatments. In most cases, these were linseed oil-based glazings (the use of this substance is confirmed by historical documents) and pigments. Their role was essentially aesthetic; their use dates the beginning of the fourteenth century and continued at least until the eighteenth century.

Some Insights on the Aterian in the Libyan Sahara: Chronology, Environment, and Archaeology

The Aterian has a huge geographic extension covering all North Africa, although it was not supposed to exist in the mountain ranges of the central Sahara. Its chronological context is not yet definitively determined and it is still difficult to say whether the Aterian tools are technological, typological, functional, or chronological markers. Recent surveys and excavations at Uan Tabu and Uan Afuda, two rock-shelters located in the central Tadrart Acacus, provide the first chronological, environmental and archaeological indications on this Late Pleistocene human occupation in the area. The lack of organic matter led us to perform OSL and TL analyses on sand. L'Atérien a une énorme extension géographique qui couvre tout le Nord de l'Afrique, tandis qu'on ne pensait pas qu'il existait dans les montagnes du Sahara central. Son contexte culturel n'est pas définitivement déterminé et il est encore difficile de dire si les instruments atériens sont des indicateurs téchnologiques, typologiques, fonctionels ou culturels. Reconnaissances et fouilles récentes à Uan Tabu et Uan Afuda, deux abris situés dans l'Acacous central, fournissent les premières indications sur la chronologie, l'environnement et l'archéologie de l'Atérien dans la région. L'absence de la substance organique, nous a porté à faire des déterminations OSL et TL sur les sables.     

Sailing virtual canoes across Oceania: revisiting island accessibility

Understanding sailing conditions is a basic requirement for understanding the two periods of settlement of the distant islands of Oceania, initially from the Bismarck Islands off New Guinea as far as Samoa and later from Samoa throughout East Polynesia. The question of a “navigational threshold” between these two worlds is the focus of this paper. A computer simulation is presented that quantifies the difficulty of sailing virtual canoes in the differing wind conditions in both areas. The model demonstrates substantial differences in ease of voyaging up to and beyond Samoa. That this measure is so markedly different between these two worlds gives support for the hypothesised pause between the discovery and settlement of islands West and East of Samoa.