RESUMO
The purpose of this work is to provide the methodological and instrumental framework for the establishment of a new absolute gravity and height reference network in Sicily. The aim of the network is to contribute to the new reference systems in the Italian area, useful for the scientific and technological activities related to the gravity field and to the proper definition of a modern height system in this region. The network is composed of 5 stations, evenly distributed to form a large mesh, which roughly covers the entire Sicily. Since four of the five selected stations were measured also in the 1990s, it was also possible to evaluate whether long-term gravity changes occurred at these sites (basic requirement for a reference network) and check the long-term ground deformation patterns, using data from the closest GPS/GNSS stations. The observed gravity changes over a time interval of about 30 years at the absolute stations and in the surrounding areas, confirm the long-term stability of the selected areas/sites.
RESUMO
We provide a dataset of 3D coordinate time series of 37 continuous GNSS stations installed for stability monitoring purposes on onshore and offshore industrial settlements along a NW-SE-oriented and ~100-km-wide belt encompassing the eastern Italian coast and the Adriatic Sea. The dataset results from the analysis performed by using different geodetic software (Bernese, GAMIT/GLOBK and GIPSY) and consists of six raw position time series solutions, referred to IGb08 and IGS14 reference frames. Time series analyses and comparisons evidence that the different solutions are consistent between them, despite the use of different software, models, strategy processing and frame realizations. We observe that the offshore stations are subject to significant seasonal oscillations probably due to seasonal environmental loads, seasonal temperature-induced platform deformation and hydrostatic pressure variations. Many stations are characterized by non-linear time series, suggesting a complex interplay between regional (long-term tectonic stress) and local sources of deformation (e.g. reservoirs depletion, sediment compaction). Computed raw time series, logs files, phasor diagrams and time series comparison plots are distributed via PANGAEA ( https://www.pangaea.de ).
RESUMO
The Messina Strait, that separates peninsular Italy from Sicily, is one of the most seismically active areas of the Mediterranean. The structure and seismotectonic setting of the region are poorly understood, although the area is highly populated and important infrastructures are planned there. New seismic reflection data have identified a number of faults, as well as a crustal scale NE-trending anticline few km north of the strait. These features are interpreted as due to active right-lateral transpression along the north-eastern Sicilian offshore, coexisting with extensional and right-lateral transtensional tectonics in the southern Messina Strait. This complex tectonic network appears to be controlled by independent and overlapping tectonic settings, due to the presence of a diffuse transfer zone between the SE-ward retreating Calabria subduction zone relative to slab advance in the western Sicilian side.