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The Project "Application of innovative of very high resolution seismic methodologies in shallow waters aimed at the study of the subsoil of the Venice Lagoon" allowed the characterization of the Late Pleistocene and Holocene depositional sequences with a detail, that has never been reached in the past. A boat, particularly suitable for very high resolution seismic survey in shallow water (less than 1 m deep) has been fully equipped and tested. It allowed to carried out surveys of specific areas of the Lagoon that have never been investigated in the past. Moreover a seismo-stratigraphic model of the lagoon and gulf of Venice subsoil has been performed. The seismic acquisition system allowed to investigate the subsoil down to 30-40 m deep. The new data provided significant geological features related to the Late Pleistocene and Holocene evolution of the investigated areas: the southern lagoon, the Lido and Chioggia inlets and part of the shelf of the Gulf of Venice.

We present a general bathymetric map of Lago Fagnano, the largest ice-free lake of the Southern Hemisphere, located in the central part of the Tierra del Fuego Island. The map has been obtained compiling all the available bathymetric soundings and depth-converted high-resolution seismic profiles, collected in the course of several geophysical campaigns. The lake occupies a 110-km long, E-W trending tectonic depression within the southernmost tip of the Andean Cordillera, where the South America-Scotia plate boundary traverses the Tierra del Fuego Island. The map allows us to identify the main morpho-bathymetric features of Lago Fagnano. The lake floor is divided into two principal sectors of different water depths, separated by a main shoal located in the central part of the lake. Maximum water depth (206 m) is found in the eastern part, whereas water depths in the western half do not exceed 165 m. In this paper, we describe the geometry and the general morphological characteristics of the basin, which was generated by a combination of distinct tectonic processes, and later superposed by Late Quaternary glacial and glacio-lacustrine dynamic events. Fil: Zanolla, C.. Istituto Nazionale di Oceanografia e di Geofisica Sperimentale; Italia Fil: Lodolo, E.. Istituto Nazionale di Oceanografia e di Geofisica Sperimentale ; Italia Fil: Lippai, Horacio Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; Argentina; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Geología. Instituto de Geofísica "Daniel Valencio"; Argentina Fil: Tassone, Alejandro Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; Argentina; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Geología. Instituto de Geofísica "Daniel Valencio"; Argentina Fil: Menichetti, M.. Università di Urbino; Italia Fil: Baradello, L.. Istituto Nazionale di Oceanografia e di Geofisica Sperimentale; Italia Fil: Grossi, H. L.. Istituto Nazionale di Oceanografia e di Geofisica Sperimentale; Italia Fil: Hormaechea, Jose Luis. Estación Astronomica de Río Grande; Argentina

An international archaeological and geophysical expedition was carried out to study Iron Age tombs of the Saka culture in southeastern Kazakhstan. Single-fold and multifold ground-penetrating radar (GPR) surveys, in two and two and a half dimensions, focused on the identification of burial chambers beneath the mound-shaped Saka tumuli, named kourgans. Primary objectives of the geophysical study were the testing and optimization of GPR techniques for studying this type of tomb and the reconstruction of subsurface images of use for the design of archaeological excavations. Single-fold GPR grids with line spacing ranging between 50 and 200 cm were obtained at each of the 13 sites selected. After identification of the sectors of major potential interest from data processing performed directly in the field and interpretation of the single-fold grids, multifold profiles with average 1200 per cent fold were designed and performed. Processing of the data focused on velocity analyses, pre-stack coherent noise attenuation by means of FK and KL filters, stacking and analysis of the instantaneous attributes of the complex radar trace. Multifold GPR data processing techniques achieved a substantial increment in the signal to noise ratio at most sites, allowed accurate depth conversions of the stacked profiles (average deviation of estimated target location from the actual target was less than 5% of total depth) and provided indications to identify the characteristic response from the target of interest through the joint interpretation of pre-stack gathers, velocity analysis and amplitude versus offset analysis. Interpretation of stacked sections and three-dimensional models obtained from the single-fold/multifold grid allowed the identification of a burial chamber located at an estimated depth of 140–150 cm, which was excavated successfully by the archaeological team. Further reflectors with similar characteristics are shown from other sites, which will be excavated by the next archaeological expeditions to the area. Copyright © 2001 John Wiley & Sons, Ltd.

A 2.5-D and 3-D multi-fold GPR survey was carried out in the Archaeological Park of Aquileia (northern Italy). The primary objective of the study was the identification of targets of potential archaeological interest in an area designated by local archaeological authorities. The second geophysical objective was to test 2-D and 3-D multi-fold methods and to study localised targets of unknown shape and dimensions in hostile soil conditions. Several portions of the acquisition grid were processed in common offset (CO), common shot (CSG) and common mid point (CMP) geometry. An 8×8 m area was studied with orthogonal CMPs thus achieving a 3-D subsurface coverage with azimuthal range limited to two normal components. Coherent noise components were identified in the pre-stack domain and removed by means of FK filtering of CMP records. Stack velocities were obtained from conventional velocity analysis and azimuthal velocity analysis of 3-D pre-stack gathers. Two major discontinuities were identified in the area of study. The deeper one most probably coincides with the paleosol at the base of the layer associated with activities of man in the area in the last 2500 years. This interpretation is in agreement with the results obtained from nearby cores and excavations. The shallow discontinuity is observed in a part of the investigated area and it shows local interruptions with a linear distribution on the grid. Such interruptions may correspond to buried targets of archaeological interest. The prominent enhancement of the subsurface images obtained by means of multi-fold techniques, compared with the relatively poor quality of the conventional single-fold georadar sections, indicates that multi-fold methods are well suited for the application to high resolution studies in archaeology.

A combined Ground Penetrating Radar (GPR) and magnetic survey was carried out in the Aquileia Archaeologecal Park (AAP, Italy) to assess the archaeological potential of a 5.000 sqm area intended for road construction.

A 3D multi-fold GPR investigation was carried out in the archaeological park of Aquileia in the framework of a survey proposed by the local superintendency of cultural heritage. Primary objective of the work was the identification of targets of potential archaeological interest in a polygon of approximately 2800 sqm in area, which borders the town cemetery to the north. The comparison of single-fold and multi-fold test profiles encouraged the design of a complete multi-fold grid. The 3-D option was chosen to correlate and map targets of limited dimensions. Targets of possible archaeological interest were identified at estimated depths not exceeding 200 cm in the part of the dataset processed to date.