Daniela Tarallo

Application of X-Band Wave Radar for Coastal Dynamic Analysis: Case Test of Bagnara Calabra (South Tyrrhenian Sea, Italy)

Sea state knowledge has a key role in evaluation of coastal erosion, the assessment of vulnerability and potential in coastal zone utilization, and development of numerical models to predict its evolution. X-band radar measurements were conducted to observe the spatial and temporal variation of the sea-state parameters along a 3 km long sandy-gravelly pocket beaches forming a littoral cell on Bagnara Calabra. We produced a sequence of 1000 images of the sea state extending offshore up to 1 mile. The survey has allowed monitoring the coastline, the directional wave spectra, the sea surface current fields, and the significant wave heights and detecting strong rip currents which cause scours around the open inlets and affect the stability of the submerged reef-type breakwaters. The possibility to validate the data acquired with other datasets (e.g., LaMMA Consortium) demonstrates the potential of the X-band radar technology as a monitoring tool to advance the understanding of the linkages between sea conditions, nearshore sediment dynamics, and coastal change. This work proves the possibility to obtain relevant information (e.g., wave number, period, and direction) for evaluation of local erosion phenomena and of morphological changes in the nearshore and surf zone.

Integrated hierarchical geo-environmental survey strategy applied to the detection and investigation of an illegal landfill: A case study in the Campania Region (Southern Italy)

This paper describes an approach to detect and investigate the main characteristics of a solid waste landfill through the integration of geological, geographical and geophysical methods. In particular, a multi-temporal analysis of the landfill morphological evolution was carried out using aerial and satellite photos, since there were no geological and geophysical data referring to the study area. Subsequently, a surface geophysical prospection was performed through geoelectric and geomagnetic methods. In particular, the combination of electrical resistivity, induced polarization and magnetic measurements removed some of the uncertainties, generally associated with a separate utilization of these techniques. This approach was successfully tested to support the Prosecutor Office of Salerno (S Italy) during a specific investigation about an illegal landfill. All the collected field data supported the reconstruction of the site-specific history, while the real quarry geometry and site geology were defined. Key elements of novelty of this method are the combination and the integration of different methodological approaches, as the parallel and combined use of satellite, aerial and in-situ collected data, that were validated in a real investigation and that revealed the effectiveness of this strategy.

Shallow Seismic Refraction Tomography and MASW Survey for Investigating the Fractures Along Qena-Safaga Road, South of Egypt

Qena-Safaga road, which is one of the vital transportation lines in south of Egypt, is affected by a set of recent NE-SW to ENE-WSW vertical tensile and en echelon fractures. These fractures are distributed for about 12 km along both sides of the road and constitute a major threat to the infrastructure and environment. Some studies suggested the tectonic origin of these fractures while others suggested that they were formed due to geotechnical problems in the shallow subsurface soil. In order to study the nature and distribution of these fractures in the subsurface, low cost seismic surveys were conducted at the area of KM 22 of Qena-Safaga road. Eleven shallow seismic refraction lines as well as three MASW lines were acquired. The seismic refraction data were analyzed using tomographic methods to produce 2D velocity-depth models. To estimate the near surface seismic properties such as Vp/Vs and Poisson’s ratio that are important for the geologic interpretation of the data, MASW data where analyzed to obtain 1D shear wave velocity models. 3D images including 3D volume, fence diagram and depth slices were also produced to study the vertical and lateral variation of the P-wave velocity. In the resulted 2D tomographic models, three seismic units were deduced. The first unit represents the thin weathered surface layer having P-wave velocities of 300–700 m/s. The second unit has P-wave velocities of 700–1600 m/s and S-wave velocities of 281–926 m/s. It may represent the marl unit of Pliocene Durri Formation. Its thickness ranges from 11.8 m to 30 m. The bedrock was deduced to be at depths from 13 to 40 m and is characterized by velocities greater than 1600 m/s. The fractures were traced down to the bedrock along the seismic sections. The variable thickness of the marl unit as well as the variable depths of the bedrock were deduced to be resulting from the effect of subsurface.