Restoration of vintage gravity data and comparison with new satellite-derived models in two case studies: the Gulf of Manfredonia and the Friulian Plain/North Adriatic

The central aspect of this thesis is the recovery, homogenization, and validation of the enormous amount of vintage gravimetric and magnetic data acquired by OGS since the early 1960s, both at sea and onshore in the Italian territory. It is a wealth of geophysical data that today would be unthinkable to acquire because of the unsustainable costs and logistic difficulties. A further important aspect of the work is the comparison with satellite-derived data, analyzed through two specific case studies (North Adriatic/Friuli Plain and Manfredonia Gulf – SW Adriatic). A great effort has been made to evaluate whether gravimetric data acquired in different periods, with different tools and processing techniques, can be used for geological studies after appropriate checks and homogenization. Nowadays, with the new interpretation techniques, it is possible to extract further and more accurate information from the same datasets and merge them with the more recent acquisition technique, including satellite-based models. Moreover, data restoration is often a crucial factor in addressing new research projects and scientific explorations. Three different gravity data types were collected and merged to create the most detailed and homogeneous view of gravity anomalies in the study regions: (i) sea-bottom, (ii) sea surface, and (iii) land-based gravity. Different processing methods have been tested to reduce all possible data errors and signals unrelated to the investigated targets. We reduce crossover errors in sea-surface gravity lines using a remove-restore method which combines the long-wavelength signals of satellite altimeter-derived models with the short-wavelength of shipborne data. This work represents one of the few examples in which vintage geophysical data have been restored and validated. This is an important dataset that can be made available to the scientific community for joint studies and that allows deepening study areas in which the availability of data is scarce. The procedures and methods that have been applied and discussed in this thesis, through examples of case studies and the realization of geological models in-depth, have demonstrated the validity of the approach and provided a key for future studies involving the use of vintage geophysical data.