Andrea Ninfo

The Map of Altinum, Ancestor of Venice

Arial mapping during an extreme drought has revealed the detailed plan of a major Roman city in the Venice lagoon. Processing and interpretation of July 2007 digital visible and near-infrared aerial photographs, coupled by a digital terrain model, has allowed for detailed reconstruction of the topography and the paleoenvironmental setting of the Roman city of Altinum, shedding new light on the far origins of Venice. Images were taken during severe dry conditions, which stressed the maize and soy crops. The city walls and doors, the street network, dwellings, theaters, amphitheater, forum, emporia, basilica, and a complex network of rivers and canals have been mapped.

Morphological Analysis for Architectural Applications: Comparison between Laser Scanning and Structure-from-Motion Photogrammetry

AbstractTerrestrial laser scanning (TLS) and structure-from-motion photogrammetry (SfM) can both provide dense and accurate point clouds. Therefore, they can be used to perform a morphological analysis of the facades of a masonry building, which relies on evaluation of the differences between the point cloud and a reference regular surface fitted to it. To compare TLS and SfM performance in morphological analysis, multimodal surveys were carried out on the square cross-section, 48-m-high Garisenda Tower in Bologna, Italy (reference surface: plane), and the circle cross-section, 42-m-high Caorle’s leaning bell tower in Venice, Italy (reference surface: moving cylinder). The results show that the TLS- and SfM-based morphologies are qualitatively the same, and the relative differences are lower than 10%–20% under the condition that the viewpoint positions (VPs) are optimal. Also, the overall geometries are correctly described by both the techniques. The main conclusion is that, if no particular constraints e...

HVSR technique in near-surface thermal-basin characterization: the example of the Caldiero district (North-East Italy)

AbstractIn the present work, non-invasive microtremor survey is applied for the preliminary characterization of the thermal district of Caldiero, in the eastern Po Plain (Italy), a thermal resource known since the Roman times for the presence of warm springs. The work’s aim was to test the suitability of the microtremor passive technique for the preliminary characterization of a thermal basin, in terms of resonance properties between the alluvial deposit covers and the rocky bedrock. In particular, the horizontal-to-vertical spectral ratio (HVSR) single-station technique is adopted to estimate the resonance properties of the geothermal basin. More than 100 HVSR single-station measurements are collected and analyzed in the area studied. HVSR information is integrated with the findings of the analysis of the data relative to more than 20 deep wells. Such an integration permits the calibration for validation of the geophysical data. The correlation between the results from microtremor survey, LiDAR data analysis, and wells information highlighted the main geological structures of the site, which are potentially responsible for the thermal waters arising. HVSR results are then interpreted in terms of regional geological setting, textural, and hydrogeological properties of the superficial deposits and the underlying rocky bedrock. The results of this method confirm the existence of significant correlations between the resonance behavior of the basin, as determined by the HVSR technique, and the geological assessment. This suggests that the single-station technique could be a very promising tool for a rapid and preliminary non-invasive method for the near-surface general characterization of geothermal basins.