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In Antarctica, the severe climatic conditions and the thick ice sheet that covers the largest and most internal part of the continent make it particularly difficult to systematically carry out geophysical and geodetic observations on a continental scale. It prevents the comprehensive understanding of both the onshore and offshore geology as well as the relationship between the inner part of East Antarctica (EA) and the coastal sector of Victoria Land (VL). With the aim to reduce this gap, in this paper multiple geophysical dataset collected since the 1980s in Antarctica by Programma Nazionale di Ricerche in Antartide (PNRA) were integrated with geodetic observations. In particu-lar, the analyzed data includes: (i) Geodetic time series from Trans Antarctic Mountains DEFormation (TAMDEF), and Victoria Land Network for DEFormation control (VLNDEF) GNSS stations installed in Victoria Land; (ii) the integration of on-shore (ground points data and airborne) gravity measurements in Victoria Land and marine gravity surveys performed in the Ross Sea and the nar-row strip of Southern Ocean facing the coasts of northern Victoria Land. Gravity data modelling has improved the knowledge of the Moho depth of VL and surrounding the offshore areas. By the integration of geodetic and gravitational (or gravity) potential results it was possible to better con-strain/identify four geodynamic blocks characterized by homogeneous geophysical signature: the Southern Ocean to the N, the Ross Sea to the E, the Wilkes Basin to the W, and VL in between. The last block is characterized by a small but significant clockwise rotation relative to East Antarctica. The presence of a N-S to NNW-SSE 1-km step in the Moho in correspondence of the Rennick Geo-dynamic Belt confirms the existence of this crustal scale discontinuity, possibly representing the tectonic boundary between East Antarctica and the northern part of VL block, as previously pro-posed by some geological studies.

We present here LARGE 0.2.0 (Lithosphere AsthenospheRe Geodynamic Evolution) a geodynamic modelling Python package that implements a flexible and user friendly tool for the geodynamic/modelling community. It simulates 2D large scale geodynamic processes by solving the conservation equations of mass, momentum, and energy by a finite difference method with the moving tracers technique. LARGE uses advanced modern numerical libraries and algorithms but unlike common simulation code written in Fortran or C this code is written entirely in Python. Simulations are driven by configuration files that define thoroughly the lithologies and the parameters that distinguish the model. Documentation for them and for all the modules is included in the package together with a complete set of examples and utilities. The package can be used to reproduce results of published studies and models or to experiment new simulations. LARGE can run in serial mode on desktop computers but can take advantage of MPI to run in parallel on multi node HPC systems.

In this study, we present a comparative analysis between two types of gravity data used in geophysical applications: satellite altimeter-derived gravity and sea-bottom gravity.It is largely known that the marine gravity field derived from satellite altimetry in coastal areas is generally biased by signals back-scattered from the nearby land. As a result, the derived gravity anomalies are mostly unreliable for geophysical and geological interpretations of near-shore environments.To quantify the errors generated by the land-reflected signals and to verify the goodness of the geologic models inferred from gravity, we compared two different altimetry models with sea-bottom gravity measurements acquired along the Italian coasts from the early 50s to the late 80s.We focused on the Gulf of Manfredonia, located in the SE sector of the Adriatic Sea, where: (i) two different sea-bottom gravity surveys have been conducted over the years, (ii) the bathymetry is particularly flat, and (iii) seismic data revealed a prominent carbonate ridge covered by hundreds of meters of Oligocene-Quaternary sediments.Gravity field derivatives have been used to enhance both: (i) deep geological contacts, and (ii) coastal noise. The analyses outlined a “ringing-noise effect” which causes the altimeter signal degradation up to 17 km from the coast.Differences between the observed gravity and the gravity calculated from a geological model constrained by seismic, showed that all datasets register approximately the same patterns, associated with the Gondola Fault Zone, a major structural discontinuity traversing roughly E-W the investigated area.This study highlights the importance of implementing gravity anomalies derived from satellite-altimetry with high-resolution near-shore data, such as the sea-bottom gravity measurements available around the Italian coasts. Such analysis may have significant applications in studying the link between onshore and offshore geological structures in transitional areas.

Vector fields visualization is quite common in many scientific disciplines and many methods have been developed for this purpose. Python is probably the ideal glue language to write applications that exploit the capabilities of modern graphic cards through the Open Graphics Library. A brief introduction to Python and OpenGL will preface our approach in writing easily reusable code to create a Python package to represent vector fields through particles that move along the flow lines of the field at a speed and color proportional to its modulus. An example application will be shown to illustrate how interactive control of speed, color and number of animated particles is possible as the whole rendering process happens in the GPU in real time. A background image can be shown to add information for the interpretation of the results. Keywords: Python, OpenGL, Vector field, Animation

In this paper, the relatively deep (up to 90 km) seismicity of central Italy is considered in comparison with the upper crust seismicity at the outer front of the Apennine fold-and-thrust belt system and with the major crust-scale tectonic discontinuities outlined by deep crust seismic reflection and refraction profiles. In particular, attention is given to the presence of a Plio-Quaternary SW-dipping thrust zone cutting the entire Adriatic crust and emerging at the outer front of the Apennine thrust system, along the Po Plain-Adriatic belt. This discontinuity, detectable from the CROP 03 near-vertical seismic reflection profile, but only partially highlighted in previous studies, is here named Adriatic Thrust (AT). The geometry of the AT is compared with the distribution and kinematics of the Coastal-Adriatic upper crust seismicity, of the Marche Foothill lower crust seismicity and of the Apennine deep seismicity (base of the crust and upper mantle). A good spatial correspondence between the down-dip fault geometry and the seismicity is observed. The rheological stratification of the lithosphere controls the location of the seismic activity at different depth intervals along the fault plane (0–10, 15–25, 35–45 km). The reconstructed rheological conditions do not allow to justify in terms of brittle behavior the deepest earthquakes, located at depths from 55 to 70 km within the possible down-dip intra-mantle prosecution of the AT. These events might represent either co-seismic plastic instabilities due to high strain concentrations within the AT shear zone or seismic failure of the continental Adriatic lithosphere due to a strong increase in pore fluid pressure (infiltration from the asthenosphere of hydroxil-CO2 rich volatiles). The proposed interpretation of the AT as a lithosphere-scale seismogenic fault zone, has several implications: (1) the Po Plain-Adriatic front of the Apennine thrust system is still active; (2) the Apennine deep seismicity is not associated with a SW-dipping subduction plane; (3) seismogenic deformation in association with lithospheric failure is possible.